Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 1 | /* |
| 2 | * File: drivers/pci/pcie/aspm.c |
Stefan Assmann | 45e829e | 2009-12-03 06:49:24 -0500 | [diff] [blame] | 3 | * Enabling PCIe link L0s/L1 state and Clock Power Management |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 4 | * |
| 5 | * Copyright (C) 2007 Intel |
| 6 | * Copyright (C) Zhang Yanmin (yanmin.zhang@intel.com) |
| 7 | * Copyright (C) Shaohua Li (shaohua.li@intel.com) |
| 8 | */ |
| 9 | |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/moduleparam.h> |
| 13 | #include <linux/pci.h> |
| 14 | #include <linux/pci_regs.h> |
| 15 | #include <linux/errno.h> |
| 16 | #include <linux/pm.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/slab.h> |
Thomas Renninger | 2a42d9d | 2008-12-09 13:05:09 +0100 | [diff] [blame] | 19 | #include <linux/jiffies.h> |
Andrew Patterson | 987a4c7 | 2009-01-05 16:21:04 -0700 | [diff] [blame] | 20 | #include <linux/delay.h> |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 21 | #include <linux/pci-aspm.h> |
| 22 | #include "../pci.h" |
| 23 | |
| 24 | #ifdef MODULE_PARAM_PREFIX |
| 25 | #undef MODULE_PARAM_PREFIX |
| 26 | #endif |
| 27 | #define MODULE_PARAM_PREFIX "pcie_aspm." |
| 28 | |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 29 | /* Note: those are not register definitions */ |
| 30 | #define ASPM_STATE_L0S_UP (1) /* Upstream direction L0s state */ |
| 31 | #define ASPM_STATE_L0S_DW (2) /* Downstream direction L0s state */ |
| 32 | #define ASPM_STATE_L1 (4) /* L1 state */ |
| 33 | #define ASPM_STATE_L0S (ASPM_STATE_L0S_UP | ASPM_STATE_L0S_DW) |
| 34 | #define ASPM_STATE_ALL (ASPM_STATE_L0S | ASPM_STATE_L1) |
| 35 | |
Kenji Kaneshige | b6c2e54 | 2009-05-13 12:14:58 +0900 | [diff] [blame] | 36 | struct aspm_latency { |
| 37 | u32 l0s; /* L0s latency (nsec) */ |
| 38 | u32 l1; /* L1 latency (nsec) */ |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 39 | }; |
| 40 | |
| 41 | struct pcie_link_state { |
Kenji Kaneshige | 5cde89d | 2009-05-13 12:17:04 +0900 | [diff] [blame] | 42 | struct pci_dev *pdev; /* Upstream component of the Link */ |
Kenji Kaneshige | 5c92ffb | 2009-05-13 12:23:57 +0900 | [diff] [blame] | 43 | struct pcie_link_state *root; /* pointer to the root port link */ |
Kenji Kaneshige | 5cde89d | 2009-05-13 12:17:04 +0900 | [diff] [blame] | 44 | struct pcie_link_state *parent; /* pointer to the parent Link state */ |
| 45 | struct list_head sibling; /* node in link_list */ |
| 46 | struct list_head children; /* list of child link states */ |
| 47 | struct list_head link; /* node in parent's children list */ |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 48 | |
| 49 | /* ASPM state */ |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 50 | u32 aspm_support:3; /* Supported ASPM state */ |
| 51 | u32 aspm_enabled:3; /* Enabled ASPM state */ |
| 52 | u32 aspm_capable:3; /* Capable ASPM state with latency */ |
| 53 | u32 aspm_default:3; /* Default ASPM state by BIOS */ |
| 54 | u32 aspm_disable:3; /* Disabled ASPM state */ |
Kenji Kaneshige | 80bfdbe | 2009-05-13 12:12:43 +0900 | [diff] [blame] | 55 | |
Kenji Kaneshige | 4d246e4 | 2009-05-13 12:15:38 +0900 | [diff] [blame] | 56 | /* Clock PM state */ |
| 57 | u32 clkpm_capable:1; /* Clock PM capable? */ |
| 58 | u32 clkpm_enabled:1; /* Current Clock PM state */ |
| 59 | u32 clkpm_default:1; /* Default Clock PM state by BIOS */ |
| 60 | |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 61 | /* Exit latencies */ |
| 62 | struct aspm_latency latency_up; /* Upstream direction exit latency */ |
| 63 | struct aspm_latency latency_dw; /* Downstream direction exit latency */ |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 64 | /* |
Kenji Kaneshige | b6c2e54 | 2009-05-13 12:14:58 +0900 | [diff] [blame] | 65 | * Endpoint acceptable latencies. A pcie downstream port only |
| 66 | * has one slot under it, so at most there are 8 functions. |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 67 | */ |
Kenji Kaneshige | b6c2e54 | 2009-05-13 12:14:58 +0900 | [diff] [blame] | 68 | struct aspm_latency acceptable[8]; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 69 | }; |
| 70 | |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 71 | static int aspm_disabled, aspm_force; |
Rafael J. Wysocki | 8b8bae9 | 2011-03-05 13:21:51 +0100 | [diff] [blame] | 72 | static bool aspm_support_enabled = true; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 73 | static DEFINE_MUTEX(aspm_lock); |
| 74 | static LIST_HEAD(link_list); |
| 75 | |
| 76 | #define POLICY_DEFAULT 0 /* BIOS default setting */ |
| 77 | #define POLICY_PERFORMANCE 1 /* high performance */ |
| 78 | #define POLICY_POWERSAVE 2 /* high power saving */ |
| 79 | static int aspm_policy; |
| 80 | static const char *policy_str[] = { |
| 81 | [POLICY_DEFAULT] = "default", |
| 82 | [POLICY_PERFORMANCE] = "performance", |
| 83 | [POLICY_POWERSAVE] = "powersave" |
| 84 | }; |
| 85 | |
Andrew Patterson | 987a4c7 | 2009-01-05 16:21:04 -0700 | [diff] [blame] | 86 | #define LINK_RETRAIN_TIMEOUT HZ |
| 87 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 88 | static int policy_to_aspm_state(struct pcie_link_state *link) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 89 | { |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 90 | switch (aspm_policy) { |
| 91 | case POLICY_PERFORMANCE: |
| 92 | /* Disable ASPM and Clock PM */ |
| 93 | return 0; |
| 94 | case POLICY_POWERSAVE: |
| 95 | /* Enable ASPM L0s/L1 */ |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 96 | return ASPM_STATE_ALL; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 97 | case POLICY_DEFAULT: |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 98 | return link->aspm_default; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 99 | } |
| 100 | return 0; |
| 101 | } |
| 102 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 103 | static int policy_to_clkpm_state(struct pcie_link_state *link) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 104 | { |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 105 | switch (aspm_policy) { |
| 106 | case POLICY_PERFORMANCE: |
| 107 | /* Disable ASPM and Clock PM */ |
| 108 | return 0; |
| 109 | case POLICY_POWERSAVE: |
| 110 | /* Disable Clock PM */ |
| 111 | return 1; |
| 112 | case POLICY_DEFAULT: |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 113 | return link->clkpm_default; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 114 | } |
| 115 | return 0; |
| 116 | } |
| 117 | |
Kenji Kaneshige | 430842e | 2009-05-13 12:20:10 +0900 | [diff] [blame] | 118 | static void pcie_set_clkpm_nocheck(struct pcie_link_state *link, int enable) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 119 | { |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 120 | int pos; |
| 121 | u16 reg16; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 122 | struct pci_dev *child; |
| 123 | struct pci_bus *linkbus = link->pdev->subordinate; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 124 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 125 | list_for_each_entry(child, &linkbus->devices, bus_list) { |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 126 | pos = pci_pcie_cap(child); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 127 | if (!pos) |
| 128 | return; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 129 | pci_read_config_word(child, pos + PCI_EXP_LNKCTL, ®16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 130 | if (enable) |
| 131 | reg16 |= PCI_EXP_LNKCTL_CLKREQ_EN; |
| 132 | else |
| 133 | reg16 &= ~PCI_EXP_LNKCTL_CLKREQ_EN; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 134 | pci_write_config_word(child, pos + PCI_EXP_LNKCTL, reg16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 135 | } |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 136 | link->clkpm_enabled = !!enable; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 137 | } |
| 138 | |
Kenji Kaneshige | 430842e | 2009-05-13 12:20:10 +0900 | [diff] [blame] | 139 | static void pcie_set_clkpm(struct pcie_link_state *link, int enable) |
| 140 | { |
| 141 | /* Don't enable Clock PM if the link is not Clock PM capable */ |
| 142 | if (!link->clkpm_capable && enable) |
Matthew Garrett | 2f671e2 | 2010-12-06 14:00:56 -0500 | [diff] [blame] | 143 | enable = 0; |
Kenji Kaneshige | 430842e | 2009-05-13 12:20:10 +0900 | [diff] [blame] | 144 | /* Need nothing if the specified equals to current state */ |
| 145 | if (link->clkpm_enabled == enable) |
| 146 | return; |
| 147 | pcie_set_clkpm_nocheck(link, enable); |
| 148 | } |
| 149 | |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 150 | static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 151 | { |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 152 | int pos, capable = 1, enabled = 1; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 153 | u32 reg32; |
| 154 | u16 reg16; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 155 | struct pci_dev *child; |
| 156 | struct pci_bus *linkbus = link->pdev->subordinate; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 157 | |
| 158 | /* All functions should have the same cap and state, take the worst */ |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 159 | list_for_each_entry(child, &linkbus->devices, bus_list) { |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 160 | pos = pci_pcie_cap(child); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 161 | if (!pos) |
| 162 | return; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 163 | pci_read_config_dword(child, pos + PCI_EXP_LNKCAP, ®32); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 164 | if (!(reg32 & PCI_EXP_LNKCAP_CLKPM)) { |
| 165 | capable = 0; |
| 166 | enabled = 0; |
| 167 | break; |
| 168 | } |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 169 | pci_read_config_word(child, pos + PCI_EXP_LNKCTL, ®16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 170 | if (!(reg16 & PCI_EXP_LNKCTL_CLKREQ_EN)) |
| 171 | enabled = 0; |
| 172 | } |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 173 | link->clkpm_enabled = enabled; |
| 174 | link->clkpm_default = enabled; |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 175 | link->clkpm_capable = (blacklist) ? 0 : capable; |
Shaohua Li | 46bbdfa | 2008-12-19 09:27:42 +0800 | [diff] [blame] | 176 | } |
| 177 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 178 | /* |
| 179 | * pcie_aspm_configure_common_clock: check if the 2 ends of a link |
| 180 | * could use common clock. If they are, configure them to use the |
| 181 | * common clock. That will reduce the ASPM state exit latency. |
| 182 | */ |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 183 | static void pcie_aspm_configure_common_clock(struct pcie_link_state *link) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 184 | { |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 185 | int ppos, cpos, same_clock = 1; |
| 186 | u16 reg16, parent_reg, child_reg[8]; |
Thomas Renninger | 2a42d9d | 2008-12-09 13:05:09 +0100 | [diff] [blame] | 187 | unsigned long start_jiffies; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 188 | struct pci_dev *child, *parent = link->pdev; |
| 189 | struct pci_bus *linkbus = parent->subordinate; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 190 | /* |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 191 | * All functions of a slot should have the same Slot Clock |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 192 | * Configuration, so just check one function |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 193 | */ |
| 194 | child = list_entry(linkbus->devices.next, struct pci_dev, bus_list); |
Kenji Kaneshige | 8b06477 | 2009-11-11 14:36:52 +0900 | [diff] [blame] | 195 | BUG_ON(!pci_is_pcie(child)); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 196 | |
| 197 | /* Check downstream component if bit Slot Clock Configuration is 1 */ |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 198 | cpos = pci_pcie_cap(child); |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 199 | pci_read_config_word(child, cpos + PCI_EXP_LNKSTA, ®16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 200 | if (!(reg16 & PCI_EXP_LNKSTA_SLC)) |
| 201 | same_clock = 0; |
| 202 | |
| 203 | /* Check upstream component if bit Slot Clock Configuration is 1 */ |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 204 | ppos = pci_pcie_cap(parent); |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 205 | pci_read_config_word(parent, ppos + PCI_EXP_LNKSTA, ®16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 206 | if (!(reg16 & PCI_EXP_LNKSTA_SLC)) |
| 207 | same_clock = 0; |
| 208 | |
| 209 | /* Configure downstream component, all functions */ |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 210 | list_for_each_entry(child, &linkbus->devices, bus_list) { |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 211 | cpos = pci_pcie_cap(child); |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 212 | pci_read_config_word(child, cpos + PCI_EXP_LNKCTL, ®16); |
| 213 | child_reg[PCI_FUNC(child->devfn)] = reg16; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 214 | if (same_clock) |
| 215 | reg16 |= PCI_EXP_LNKCTL_CCC; |
| 216 | else |
| 217 | reg16 &= ~PCI_EXP_LNKCTL_CCC; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 218 | pci_write_config_word(child, cpos + PCI_EXP_LNKCTL, reg16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 219 | } |
| 220 | |
| 221 | /* Configure upstream component */ |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 222 | pci_read_config_word(parent, ppos + PCI_EXP_LNKCTL, ®16); |
Thomas Renninger | 2a42d9d | 2008-12-09 13:05:09 +0100 | [diff] [blame] | 223 | parent_reg = reg16; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 224 | if (same_clock) |
| 225 | reg16 |= PCI_EXP_LNKCTL_CCC; |
| 226 | else |
| 227 | reg16 &= ~PCI_EXP_LNKCTL_CCC; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 228 | pci_write_config_word(parent, ppos + PCI_EXP_LNKCTL, reg16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 229 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 230 | /* Retrain link */ |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 231 | reg16 |= PCI_EXP_LNKCTL_RL; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 232 | pci_write_config_word(parent, ppos + PCI_EXP_LNKCTL, reg16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 233 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 234 | /* Wait for link training end. Break out after waiting for timeout */ |
Thomas Renninger | 2a42d9d | 2008-12-09 13:05:09 +0100 | [diff] [blame] | 235 | start_jiffies = jiffies; |
Andrew Patterson | 987a4c7 | 2009-01-05 16:21:04 -0700 | [diff] [blame] | 236 | for (;;) { |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 237 | pci_read_config_word(parent, ppos + PCI_EXP_LNKSTA, ®16); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 238 | if (!(reg16 & PCI_EXP_LNKSTA_LT)) |
| 239 | break; |
Andrew Patterson | 987a4c7 | 2009-01-05 16:21:04 -0700 | [diff] [blame] | 240 | if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) |
| 241 | break; |
| 242 | msleep(1); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 243 | } |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 244 | if (!(reg16 & PCI_EXP_LNKSTA_LT)) |
| 245 | return; |
| 246 | |
| 247 | /* Training failed. Restore common clock configurations */ |
| 248 | dev_printk(KERN_ERR, &parent->dev, |
| 249 | "ASPM: Could not configure common clock\n"); |
| 250 | list_for_each_entry(child, &linkbus->devices, bus_list) { |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 251 | cpos = pci_pcie_cap(child); |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 252 | pci_write_config_word(child, cpos + PCI_EXP_LNKCTL, |
| 253 | child_reg[PCI_FUNC(child->devfn)]); |
Thomas Renninger | 2a42d9d | 2008-12-09 13:05:09 +0100 | [diff] [blame] | 254 | } |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 255 | pci_write_config_word(parent, ppos + PCI_EXP_LNKCTL, parent_reg); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 256 | } |
| 257 | |
Kenji Kaneshige | 5e0eaa7 | 2009-05-13 12:21:48 +0900 | [diff] [blame] | 258 | /* Convert L0s latency encoding to ns */ |
| 259 | static u32 calc_l0s_latency(u32 encoding) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 260 | { |
Kenji Kaneshige | 5e0eaa7 | 2009-05-13 12:21:48 +0900 | [diff] [blame] | 261 | if (encoding == 0x7) |
| 262 | return (5 * 1000); /* > 4us */ |
| 263 | return (64 << encoding); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 264 | } |
| 265 | |
Kenji Kaneshige | 5e0eaa7 | 2009-05-13 12:21:48 +0900 | [diff] [blame] | 266 | /* Convert L0s acceptable latency encoding to ns */ |
| 267 | static u32 calc_l0s_acceptable(u32 encoding) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 268 | { |
Kenji Kaneshige | 5e0eaa7 | 2009-05-13 12:21:48 +0900 | [diff] [blame] | 269 | if (encoding == 0x7) |
| 270 | return -1U; |
| 271 | return (64 << encoding); |
| 272 | } |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 273 | |
Kenji Kaneshige | 5e0eaa7 | 2009-05-13 12:21:48 +0900 | [diff] [blame] | 274 | /* Convert L1 latency encoding to ns */ |
| 275 | static u32 calc_l1_latency(u32 encoding) |
| 276 | { |
| 277 | if (encoding == 0x7) |
| 278 | return (65 * 1000); /* > 64us */ |
| 279 | return (1000 << encoding); |
| 280 | } |
| 281 | |
| 282 | /* Convert L1 acceptable latency encoding to ns */ |
| 283 | static u32 calc_l1_acceptable(u32 encoding) |
| 284 | { |
| 285 | if (encoding == 0x7) |
| 286 | return -1U; |
| 287 | return (1000 << encoding); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 288 | } |
| 289 | |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 290 | struct aspm_register_info { |
| 291 | u32 support:2; |
| 292 | u32 enabled:2; |
| 293 | u32 latency_encoding_l0s; |
| 294 | u32 latency_encoding_l1; |
| 295 | }; |
| 296 | |
| 297 | static void pcie_get_aspm_reg(struct pci_dev *pdev, |
| 298 | struct aspm_register_info *info) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 299 | { |
| 300 | int pos; |
| 301 | u16 reg16; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 302 | u32 reg32; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 303 | |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 304 | pos = pci_pcie_cap(pdev); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 305 | pci_read_config_dword(pdev, pos + PCI_EXP_LNKCAP, ®32); |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 306 | info->support = (reg32 & PCI_EXP_LNKCAP_ASPMS) >> 10; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 307 | info->latency_encoding_l0s = (reg32 & PCI_EXP_LNKCAP_L0SEL) >> 12; |
| 308 | info->latency_encoding_l1 = (reg32 & PCI_EXP_LNKCAP_L1EL) >> 15; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 309 | pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, ®16); |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 310 | info->enabled = reg16 & PCI_EXP_LNKCTL_ASPMC; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 311 | } |
| 312 | |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 313 | static void pcie_aspm_check_latency(struct pci_dev *endpoint) |
| 314 | { |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 315 | u32 latency, l1_switch_latency = 0; |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 316 | struct aspm_latency *acceptable; |
| 317 | struct pcie_link_state *link; |
| 318 | |
| 319 | /* Device not in D0 doesn't need latency check */ |
| 320 | if ((endpoint->current_state != PCI_D0) && |
| 321 | (endpoint->current_state != PCI_UNKNOWN)) |
| 322 | return; |
| 323 | |
| 324 | link = endpoint->bus->self->link_state; |
| 325 | acceptable = &link->acceptable[PCI_FUNC(endpoint->devfn)]; |
| 326 | |
| 327 | while (link) { |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 328 | /* Check upstream direction L0s latency */ |
| 329 | if ((link->aspm_capable & ASPM_STATE_L0S_UP) && |
| 330 | (link->latency_up.l0s > acceptable->l0s)) |
| 331 | link->aspm_capable &= ~ASPM_STATE_L0S_UP; |
| 332 | |
| 333 | /* Check downstream direction L0s latency */ |
| 334 | if ((link->aspm_capable & ASPM_STATE_L0S_DW) && |
| 335 | (link->latency_dw.l0s > acceptable->l0s)) |
| 336 | link->aspm_capable &= ~ASPM_STATE_L0S_DW; |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 337 | /* |
| 338 | * Check L1 latency. |
| 339 | * Every switch on the path to root complex need 1 |
| 340 | * more microsecond for L1. Spec doesn't mention L0s. |
| 341 | */ |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 342 | latency = max_t(u32, link->latency_up.l1, link->latency_dw.l1); |
| 343 | if ((link->aspm_capable & ASPM_STATE_L1) && |
| 344 | (latency + l1_switch_latency > acceptable->l1)) |
| 345 | link->aspm_capable &= ~ASPM_STATE_L1; |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 346 | l1_switch_latency += 1000; |
| 347 | |
| 348 | link = link->parent; |
| 349 | } |
| 350 | } |
| 351 | |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 352 | static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 353 | { |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 354 | struct pci_dev *child, *parent = link->pdev; |
| 355 | struct pci_bus *linkbus = parent->subordinate; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 356 | struct aspm_register_info upreg, dwreg; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 357 | |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 358 | if (blacklist) { |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 359 | /* Set enabled/disable so that we will disable ASPM later */ |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 360 | link->aspm_enabled = ASPM_STATE_ALL; |
| 361 | link->aspm_disable = ASPM_STATE_ALL; |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 362 | return; |
| 363 | } |
| 364 | |
| 365 | /* Configure common clock before checking latencies */ |
| 366 | pcie_aspm_configure_common_clock(link); |
| 367 | |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 368 | /* Get upstream/downstream components' register state */ |
| 369 | pcie_get_aspm_reg(parent, &upreg); |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 370 | child = list_entry(linkbus->devices.next, struct pci_dev, bus_list); |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 371 | pcie_get_aspm_reg(child, &dwreg); |
| 372 | |
| 373 | /* |
| 374 | * Setup L0s state |
| 375 | * |
| 376 | * Note that we must not enable L0s in either direction on a |
| 377 | * given link unless components on both sides of the link each |
| 378 | * support L0s. |
| 379 | */ |
| 380 | if (dwreg.support & upreg.support & PCIE_LINK_STATE_L0S) |
| 381 | link->aspm_support |= ASPM_STATE_L0S; |
| 382 | if (dwreg.enabled & PCIE_LINK_STATE_L0S) |
| 383 | link->aspm_enabled |= ASPM_STATE_L0S_UP; |
| 384 | if (upreg.enabled & PCIE_LINK_STATE_L0S) |
| 385 | link->aspm_enabled |= ASPM_STATE_L0S_DW; |
| 386 | link->latency_up.l0s = calc_l0s_latency(upreg.latency_encoding_l0s); |
| 387 | link->latency_dw.l0s = calc_l0s_latency(dwreg.latency_encoding_l0s); |
| 388 | |
| 389 | /* Setup L1 state */ |
| 390 | if (upreg.support & dwreg.support & PCIE_LINK_STATE_L1) |
| 391 | link->aspm_support |= ASPM_STATE_L1; |
| 392 | if (upreg.enabled & dwreg.enabled & PCIE_LINK_STATE_L1) |
| 393 | link->aspm_enabled |= ASPM_STATE_L1; |
| 394 | link->latency_up.l1 = calc_l1_latency(upreg.latency_encoding_l1); |
| 395 | link->latency_dw.l1 = calc_l1_latency(dwreg.latency_encoding_l1); |
Kenji Kaneshige | 80bfdbe | 2009-05-13 12:12:43 +0900 | [diff] [blame] | 396 | |
Kenji Kaneshige | b127bd5 | 2009-08-19 10:57:31 +0900 | [diff] [blame] | 397 | /* Save default state */ |
| 398 | link->aspm_default = link->aspm_enabled; |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 399 | |
| 400 | /* Setup initial capable state. Will be updated later */ |
| 401 | link->aspm_capable = link->aspm_support; |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 402 | /* |
| 403 | * If the downstream component has pci bridge function, don't |
| 404 | * do ASPM for now. |
| 405 | */ |
| 406 | list_for_each_entry(child, &linkbus->devices, bus_list) { |
| 407 | if (child->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) { |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 408 | link->aspm_disable = ASPM_STATE_ALL; |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 409 | break; |
| 410 | } |
| 411 | } |
Kenji Kaneshige | b127bd5 | 2009-08-19 10:57:31 +0900 | [diff] [blame] | 412 | |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 413 | /* Get and check endpoint acceptable latencies */ |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 414 | list_for_each_entry(child, &linkbus->devices, bus_list) { |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 415 | int pos; |
Kenji Kaneshige | 5e0eaa7 | 2009-05-13 12:21:48 +0900 | [diff] [blame] | 416 | u32 reg32, encoding; |
Kenji Kaneshige | b6c2e54 | 2009-05-13 12:14:58 +0900 | [diff] [blame] | 417 | struct aspm_latency *acceptable = |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 418 | &link->acceptable[PCI_FUNC(child->devfn)]; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 419 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 420 | if (child->pcie_type != PCI_EXP_TYPE_ENDPOINT && |
| 421 | child->pcie_type != PCI_EXP_TYPE_LEG_END) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 422 | continue; |
| 423 | |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 424 | pos = pci_pcie_cap(child); |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 425 | pci_read_config_dword(child, pos + PCI_EXP_DEVCAP, ®32); |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 426 | /* Calculate endpoint L0s acceptable latency */ |
Kenji Kaneshige | 5e0eaa7 | 2009-05-13 12:21:48 +0900 | [diff] [blame] | 427 | encoding = (reg32 & PCI_EXP_DEVCAP_L0S) >> 6; |
| 428 | acceptable->l0s = calc_l0s_acceptable(encoding); |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 429 | /* Calculate endpoint L1 acceptable latency */ |
| 430 | encoding = (reg32 & PCI_EXP_DEVCAP_L1) >> 9; |
| 431 | acceptable->l1 = calc_l1_acceptable(encoding); |
| 432 | |
| 433 | pcie_aspm_check_latency(child); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 434 | } |
| 435 | } |
| 436 | |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 437 | static void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 438 | { |
| 439 | u16 reg16; |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 440 | int pos = pci_pcie_cap(pdev); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 441 | |
| 442 | pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, ®16); |
| 443 | reg16 &= ~0x3; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 444 | reg16 |= val; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 445 | pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, reg16); |
| 446 | } |
| 447 | |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 448 | static void pcie_config_aspm_link(struct pcie_link_state *link, u32 state) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 449 | { |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 450 | u32 upstream = 0, dwstream = 0; |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 451 | struct pci_dev *child, *parent = link->pdev; |
| 452 | struct pci_bus *linkbus = parent->subordinate; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 453 | |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 454 | /* Nothing to do if the link is already in the requested state */ |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 455 | state &= (link->aspm_capable & ~link->aspm_disable); |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 456 | if (link->aspm_enabled == state) |
| 457 | return; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 458 | /* Convert ASPM state to upstream/downstream ASPM register state */ |
| 459 | if (state & ASPM_STATE_L0S_UP) |
| 460 | dwstream |= PCIE_LINK_STATE_L0S; |
| 461 | if (state & ASPM_STATE_L0S_DW) |
| 462 | upstream |= PCIE_LINK_STATE_L0S; |
| 463 | if (state & ASPM_STATE_L1) { |
| 464 | upstream |= PCIE_LINK_STATE_L1; |
| 465 | dwstream |= PCIE_LINK_STATE_L1; |
| 466 | } |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 467 | /* |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 468 | * Spec 2.0 suggests all functions should be configured the |
| 469 | * same setting for ASPM. Enabling ASPM L1 should be done in |
| 470 | * upstream component first and then downstream, and vice |
| 471 | * versa for disabling ASPM L1. Spec doesn't mention L0S. |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 472 | */ |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 473 | if (state & ASPM_STATE_L1) |
| 474 | pcie_config_aspm_dev(parent, upstream); |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 475 | list_for_each_entry(child, &linkbus->devices, bus_list) |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 476 | pcie_config_aspm_dev(child, dwstream); |
| 477 | if (!(state & ASPM_STATE_L1)) |
| 478 | pcie_config_aspm_dev(parent, upstream); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 479 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 480 | link->aspm_enabled = state; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 481 | } |
| 482 | |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 483 | static void pcie_config_aspm_path(struct pcie_link_state *link) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 484 | { |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 485 | while (link) { |
| 486 | pcie_config_aspm_link(link, policy_to_aspm_state(link)); |
| 487 | link = link->parent; |
Shaohua Li | 46bbdfa | 2008-12-19 09:27:42 +0800 | [diff] [blame] | 488 | } |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 489 | } |
| 490 | |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 491 | static void free_link_state(struct pcie_link_state *link) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 492 | { |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 493 | link->pdev->link_state = NULL; |
| 494 | kfree(link); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 495 | } |
| 496 | |
Shaohua Li | ddc9753 | 2008-05-21 16:58:40 +0800 | [diff] [blame] | 497 | static int pcie_aspm_sanity_check(struct pci_dev *pdev) |
| 498 | { |
Kenji Kaneshige | 3647584 | 2009-05-13 12:23:09 +0900 | [diff] [blame] | 499 | struct pci_dev *child; |
| 500 | int pos; |
Shaohua Li | 149e163 | 2008-07-23 10:32:31 +0800 | [diff] [blame] | 501 | u32 reg32; |
Matthew Garrett | 2f671e2 | 2010-12-06 14:00:56 -0500 | [diff] [blame] | 502 | |
Matthew Garrett | 4949be1 | 2012-03-06 13:41:49 -0500 | [diff] [blame^] | 503 | if (aspm_disabled) |
| 504 | return 0; |
| 505 | |
Shaohua Li | ddc9753 | 2008-05-21 16:58:40 +0800 | [diff] [blame] | 506 | /* |
Stefan Assmann | 45e829e | 2009-12-03 06:49:24 -0500 | [diff] [blame] | 507 | * Some functions in a slot might not all be PCIe functions, |
Kenji Kaneshige | 3647584 | 2009-05-13 12:23:09 +0900 | [diff] [blame] | 508 | * very strange. Disable ASPM for the whole slot |
Shaohua Li | ddc9753 | 2008-05-21 16:58:40 +0800 | [diff] [blame] | 509 | */ |
Kenji Kaneshige | 3647584 | 2009-05-13 12:23:09 +0900 | [diff] [blame] | 510 | list_for_each_entry(child, &pdev->subordinate->devices, bus_list) { |
Kenji Kaneshige | db9538a | 2009-11-11 14:33:30 +0900 | [diff] [blame] | 511 | pos = pci_pcie_cap(child); |
Kenji Kaneshige | 3647584 | 2009-05-13 12:23:09 +0900 | [diff] [blame] | 512 | if (!pos) |
Shaohua Li | ddc9753 | 2008-05-21 16:58:40 +0800 | [diff] [blame] | 513 | return -EINVAL; |
Shaohua Li | 149e163 | 2008-07-23 10:32:31 +0800 | [diff] [blame] | 514 | /* |
| 515 | * Disable ASPM for pre-1.1 PCIe device, we follow MS to use |
| 516 | * RBER bit to determine if a function is 1.1 version device |
| 517 | */ |
Kenji Kaneshige | 3647584 | 2009-05-13 12:23:09 +0900 | [diff] [blame] | 518 | pci_read_config_dword(child, pos + PCI_EXP_DEVCAP, ®32); |
Sitsofe Wheeler | e1f4f59 | 2008-09-16 14:27:13 +0100 | [diff] [blame] | 519 | if (!(reg32 & PCI_EXP_DEVCAP_RBER) && !aspm_force) { |
Kenji Kaneshige | 3647584 | 2009-05-13 12:23:09 +0900 | [diff] [blame] | 520 | dev_printk(KERN_INFO, &child->dev, "disabling ASPM" |
Vincent Legoll | f393d9b | 2008-10-12 12:26:12 +0200 | [diff] [blame] | 521 | " on pre-1.1 PCIe device. You can enable it" |
| 522 | " with 'pcie_aspm=force'\n"); |
Shaohua Li | 149e163 | 2008-07-23 10:32:31 +0800 | [diff] [blame] | 523 | return -EINVAL; |
| 524 | } |
Shaohua Li | ddc9753 | 2008-05-21 16:58:40 +0800 | [diff] [blame] | 525 | } |
| 526 | return 0; |
| 527 | } |
| 528 | |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 529 | static struct pcie_link_state *alloc_pcie_link_state(struct pci_dev *pdev) |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 530 | { |
| 531 | struct pcie_link_state *link; |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 532 | |
| 533 | link = kzalloc(sizeof(*link), GFP_KERNEL); |
| 534 | if (!link) |
| 535 | return NULL; |
| 536 | INIT_LIST_HEAD(&link->sibling); |
| 537 | INIT_LIST_HEAD(&link->children); |
| 538 | INIT_LIST_HEAD(&link->link); |
| 539 | link->pdev = pdev; |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 540 | if (pdev->pcie_type == PCI_EXP_TYPE_DOWNSTREAM) { |
| 541 | struct pcie_link_state *parent; |
| 542 | parent = pdev->bus->parent->self->link_state; |
| 543 | if (!parent) { |
| 544 | kfree(link); |
| 545 | return NULL; |
| 546 | } |
| 547 | link->parent = parent; |
| 548 | list_add(&link->link, &parent->children); |
| 549 | } |
Kenji Kaneshige | 5c92ffb | 2009-05-13 12:23:57 +0900 | [diff] [blame] | 550 | /* Setup a pointer to the root port link */ |
| 551 | if (!link->parent) |
| 552 | link->root = link; |
| 553 | else |
| 554 | link->root = link->parent->root; |
| 555 | |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 556 | list_add(&link->sibling, &link_list); |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 557 | pdev->link_state = link; |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 558 | return link; |
| 559 | } |
| 560 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 561 | /* |
| 562 | * pcie_aspm_init_link_state: Initiate PCI express link state. |
| 563 | * It is called after the pcie and its children devices are scaned. |
| 564 | * @pdev: the root port or switch downstream port |
| 565 | */ |
| 566 | void pcie_aspm_init_link_state(struct pci_dev *pdev) |
| 567 | { |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 568 | struct pcie_link_state *link; |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 569 | int blacklist = !!pcie_aspm_sanity_check(pdev); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 570 | |
Matthew Garrett | 2f671e2 | 2010-12-06 14:00:56 -0500 | [diff] [blame] | 571 | if (!pci_is_pcie(pdev) || pdev->link_state) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 572 | return; |
| 573 | if (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 574 | pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 575 | return; |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 576 | |
Shaohua Li | 8e822df | 2009-06-08 09:27:25 +0800 | [diff] [blame] | 577 | /* VIA has a strange chipset, root port is under a bridge */ |
| 578 | if (pdev->pcie_type == PCI_EXP_TYPE_ROOT_PORT && |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 579 | pdev->bus->self) |
Shaohua Li | 8e822df | 2009-06-08 09:27:25 +0800 | [diff] [blame] | 580 | return; |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 581 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 582 | down_read(&pci_bus_sem); |
| 583 | if (list_empty(&pdev->subordinate->devices)) |
| 584 | goto out; |
| 585 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 586 | mutex_lock(&aspm_lock); |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 587 | link = alloc_pcie_link_state(pdev); |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 588 | if (!link) |
| 589 | goto unlock; |
| 590 | /* |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 591 | * Setup initial ASPM state. Note that we need to configure |
| 592 | * upstream links also because capable state of them can be |
| 593 | * update through pcie_aspm_cap_init(). |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 594 | */ |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 595 | pcie_aspm_cap_init(link, blacklist); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 596 | |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 597 | /* Setup initial Clock PM state */ |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 598 | pcie_clkpm_cap_init(link, blacklist); |
Matthew Garrett | 41cd766 | 2010-06-09 16:05:07 -0400 | [diff] [blame] | 599 | |
| 600 | /* |
| 601 | * At this stage drivers haven't had an opportunity to change the |
| 602 | * link policy setting. Enabling ASPM on broken hardware can cripple |
| 603 | * it even before the driver has had a chance to disable ASPM, so |
| 604 | * default to a safe level right now. If we're enabling ASPM beyond |
| 605 | * the BIOS's expectation, we'll do so once pci_enable_device() is |
| 606 | * called. |
| 607 | */ |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 608 | if (aspm_policy != POLICY_POWERSAVE) { |
Matthew Garrett | 41cd766 | 2010-06-09 16:05:07 -0400 | [diff] [blame] | 609 | pcie_config_aspm_path(link); |
| 610 | pcie_set_clkpm(link, policy_to_clkpm_state(link)); |
| 611 | } |
| 612 | |
Kenji Kaneshige | 8d349ac | 2009-05-13 12:18:22 +0900 | [diff] [blame] | 613 | unlock: |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 614 | mutex_unlock(&aspm_lock); |
| 615 | out: |
| 616 | up_read(&pci_bus_sem); |
| 617 | } |
| 618 | |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 619 | /* Recheck latencies and update aspm_capable for links under the root */ |
| 620 | static void pcie_update_aspm_capable(struct pcie_link_state *root) |
| 621 | { |
| 622 | struct pcie_link_state *link; |
| 623 | BUG_ON(root->parent); |
| 624 | list_for_each_entry(link, &link_list, sibling) { |
| 625 | if (link->root != root) |
| 626 | continue; |
| 627 | link->aspm_capable = link->aspm_support; |
| 628 | } |
| 629 | list_for_each_entry(link, &link_list, sibling) { |
| 630 | struct pci_dev *child; |
| 631 | struct pci_bus *linkbus = link->pdev->subordinate; |
| 632 | if (link->root != root) |
| 633 | continue; |
| 634 | list_for_each_entry(child, &linkbus->devices, bus_list) { |
| 635 | if ((child->pcie_type != PCI_EXP_TYPE_ENDPOINT) && |
| 636 | (child->pcie_type != PCI_EXP_TYPE_LEG_END)) |
| 637 | continue; |
| 638 | pcie_aspm_check_latency(child); |
| 639 | } |
| 640 | } |
| 641 | } |
| 642 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 643 | /* @pdev: the endpoint device */ |
| 644 | void pcie_aspm_exit_link_state(struct pci_dev *pdev) |
| 645 | { |
| 646 | struct pci_dev *parent = pdev->bus->self; |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 647 | struct pcie_link_state *link, *root, *parent_link; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 648 | |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 649 | if (!pci_is_pcie(pdev) || !parent || !parent->link_state) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 650 | return; |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 651 | if ((parent->pcie_type != PCI_EXP_TYPE_ROOT_PORT) && |
| 652 | (parent->pcie_type != PCI_EXP_TYPE_DOWNSTREAM)) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 653 | return; |
Kenji Kaneshige | fc87e91 | 2009-08-19 10:58:46 +0900 | [diff] [blame] | 654 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 655 | down_read(&pci_bus_sem); |
| 656 | mutex_lock(&aspm_lock); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 657 | /* |
| 658 | * All PCIe functions are in one slot, remove one function will remove |
Alex Chiang | 3419c75 | 2009-01-28 14:59:18 -0700 | [diff] [blame] | 659 | * the whole slot, so just wait until we are the last function left. |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 660 | */ |
Alex Chiang | 3419c75 | 2009-01-28 14:59:18 -0700 | [diff] [blame] | 661 | if (!list_is_last(&pdev->bus_list, &parent->subordinate->devices)) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 662 | goto out; |
| 663 | |
Kenji Kaneshige | fc87e91 | 2009-08-19 10:58:46 +0900 | [diff] [blame] | 664 | link = parent->link_state; |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 665 | root = link->root; |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 666 | parent_link = link->parent; |
Kenji Kaneshige | fc87e91 | 2009-08-19 10:58:46 +0900 | [diff] [blame] | 667 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 668 | /* All functions are removed, so just disable ASPM for the link */ |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 669 | pcie_config_aspm_link(link, 0); |
Kenji Kaneshige | fc87e91 | 2009-08-19 10:58:46 +0900 | [diff] [blame] | 670 | list_del(&link->sibling); |
| 671 | list_del(&link->link); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 672 | /* Clock PM is for endpoint device */ |
Kenji Kaneshige | fc87e91 | 2009-08-19 10:58:46 +0900 | [diff] [blame] | 673 | free_link_state(link); |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 674 | |
| 675 | /* Recheck latencies and configure upstream links */ |
Kenji Kaneshige | b26a34a | 2009-11-06 11:25:13 +0900 | [diff] [blame] | 676 | if (parent_link) { |
| 677 | pcie_update_aspm_capable(root); |
| 678 | pcie_config_aspm_path(parent_link); |
| 679 | } |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 680 | out: |
| 681 | mutex_unlock(&aspm_lock); |
| 682 | up_read(&pci_bus_sem); |
| 683 | } |
| 684 | |
| 685 | /* @pdev: the root port or switch downstream port */ |
| 686 | void pcie_aspm_pm_state_change(struct pci_dev *pdev) |
| 687 | { |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 688 | struct pcie_link_state *link = pdev->link_state; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 689 | |
Kenji Kaneshige | 8b06477 | 2009-11-11 14:36:52 +0900 | [diff] [blame] | 690 | if (aspm_disabled || !pci_is_pcie(pdev) || !link) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 691 | return; |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 692 | if ((pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT) && |
| 693 | (pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM)) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 694 | return; |
| 695 | /* |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 696 | * Devices changed PM state, we should recheck if latency |
| 697 | * meets all functions' requirement |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 698 | */ |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 699 | down_read(&pci_bus_sem); |
| 700 | mutex_lock(&aspm_lock); |
| 701 | pcie_update_aspm_capable(link->root); |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 702 | pcie_config_aspm_path(link); |
Kenji Kaneshige | 07d9276 | 2009-08-19 11:00:25 +0900 | [diff] [blame] | 703 | mutex_unlock(&aspm_lock); |
| 704 | up_read(&pci_bus_sem); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 705 | } |
| 706 | |
Naga Chumbalkar | 1a680b7 | 2011-03-21 03:29:08 +0000 | [diff] [blame] | 707 | void pcie_aspm_powersave_config_link(struct pci_dev *pdev) |
| 708 | { |
| 709 | struct pcie_link_state *link = pdev->link_state; |
| 710 | |
| 711 | if (aspm_disabled || !pci_is_pcie(pdev) || !link) |
| 712 | return; |
| 713 | |
| 714 | if (aspm_policy != POLICY_POWERSAVE) |
| 715 | return; |
| 716 | |
| 717 | if ((pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT) && |
| 718 | (pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM)) |
| 719 | return; |
| 720 | |
| 721 | down_read(&pci_bus_sem); |
| 722 | mutex_lock(&aspm_lock); |
| 723 | pcie_config_aspm_path(link); |
| 724 | pcie_set_clkpm(link, policy_to_clkpm_state(link)); |
| 725 | mutex_unlock(&aspm_lock); |
| 726 | up_read(&pci_bus_sem); |
| 727 | } |
| 728 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 729 | /* |
| 730 | * pci_disable_link_state - disable pci device's link state, so the link will |
| 731 | * never enter specific states |
| 732 | */ |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 733 | static void __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem, |
| 734 | bool force) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 735 | { |
| 736 | struct pci_dev *parent = pdev->bus->self; |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 737 | struct pcie_link_state *link; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 738 | |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 739 | if (aspm_disabled && !force) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 740 | return; |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 741 | |
| 742 | if (!pci_is_pcie(pdev)) |
| 743 | return; |
| 744 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 745 | if (pdev->pcie_type == PCI_EXP_TYPE_ROOT_PORT || |
| 746 | pdev->pcie_type == PCI_EXP_TYPE_DOWNSTREAM) |
| 747 | parent = pdev; |
| 748 | if (!parent || !parent->link_state) |
| 749 | return; |
| 750 | |
Yinghai Lu | 9f728f5 | 2011-05-12 17:11:47 -0700 | [diff] [blame] | 751 | if (sem) |
| 752 | down_read(&pci_bus_sem); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 753 | mutex_lock(&aspm_lock); |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 754 | link = parent->link_state; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 755 | if (state & PCIE_LINK_STATE_L0S) |
| 756 | link->aspm_disable |= ASPM_STATE_L0S; |
| 757 | if (state & PCIE_LINK_STATE_L1) |
| 758 | link->aspm_disable |= ASPM_STATE_L1; |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 759 | pcie_config_aspm_link(link, policy_to_aspm_state(link)); |
| 760 | |
Kenji Kaneshige | 430842e | 2009-05-13 12:20:10 +0900 | [diff] [blame] | 761 | if (state & PCIE_LINK_STATE_CLKPM) { |
Kenji Kaneshige | f1c0ca2 | 2009-08-19 10:59:52 +0900 | [diff] [blame] | 762 | link->clkpm_capable = 0; |
| 763 | pcie_set_clkpm(link, 0); |
Kenji Kaneshige | 430842e | 2009-05-13 12:20:10 +0900 | [diff] [blame] | 764 | } |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 765 | mutex_unlock(&aspm_lock); |
Yinghai Lu | 9f728f5 | 2011-05-12 17:11:47 -0700 | [diff] [blame] | 766 | if (sem) |
| 767 | up_read(&pci_bus_sem); |
| 768 | } |
| 769 | |
| 770 | void pci_disable_link_state_locked(struct pci_dev *pdev, int state) |
| 771 | { |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 772 | __pci_disable_link_state(pdev, state, false, false); |
Yinghai Lu | 9f728f5 | 2011-05-12 17:11:47 -0700 | [diff] [blame] | 773 | } |
| 774 | EXPORT_SYMBOL(pci_disable_link_state_locked); |
| 775 | |
| 776 | void pci_disable_link_state(struct pci_dev *pdev, int state) |
| 777 | { |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 778 | __pci_disable_link_state(pdev, state, true, false); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 779 | } |
| 780 | EXPORT_SYMBOL(pci_disable_link_state); |
| 781 | |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 782 | void pcie_clear_aspm(struct pci_bus *bus) |
| 783 | { |
| 784 | struct pci_dev *child; |
| 785 | |
| 786 | /* |
| 787 | * Clear any ASPM setup that the firmware has carried out on this bus |
| 788 | */ |
| 789 | list_for_each_entry(child, &bus->devices, bus_list) { |
| 790 | __pci_disable_link_state(child, PCIE_LINK_STATE_L0S | |
| 791 | PCIE_LINK_STATE_L1 | |
| 792 | PCIE_LINK_STATE_CLKPM, |
| 793 | false, true); |
| 794 | } |
| 795 | } |
| 796 | |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 797 | static int pcie_aspm_set_policy(const char *val, struct kernel_param *kp) |
| 798 | { |
| 799 | int i; |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 800 | struct pcie_link_state *link; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 801 | |
Naga Chumbalkar | bbfa306 | 2011-03-21 03:29:14 +0000 | [diff] [blame] | 802 | if (aspm_disabled) |
| 803 | return -EPERM; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 804 | for (i = 0; i < ARRAY_SIZE(policy_str); i++) |
| 805 | if (!strncmp(val, policy_str[i], strlen(policy_str[i]))) |
| 806 | break; |
| 807 | if (i >= ARRAY_SIZE(policy_str)) |
| 808 | return -EINVAL; |
| 809 | if (i == aspm_policy) |
| 810 | return 0; |
| 811 | |
| 812 | down_read(&pci_bus_sem); |
| 813 | mutex_lock(&aspm_lock); |
| 814 | aspm_policy = i; |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 815 | list_for_each_entry(link, &link_list, sibling) { |
| 816 | pcie_config_aspm_link(link, policy_to_aspm_state(link)); |
| 817 | pcie_set_clkpm(link, policy_to_clkpm_state(link)); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 818 | } |
| 819 | mutex_unlock(&aspm_lock); |
| 820 | up_read(&pci_bus_sem); |
| 821 | return 0; |
| 822 | } |
| 823 | |
| 824 | static int pcie_aspm_get_policy(char *buffer, struct kernel_param *kp) |
| 825 | { |
| 826 | int i, cnt = 0; |
| 827 | for (i = 0; i < ARRAY_SIZE(policy_str); i++) |
| 828 | if (i == aspm_policy) |
| 829 | cnt += sprintf(buffer + cnt, "[%s] ", policy_str[i]); |
| 830 | else |
| 831 | cnt += sprintf(buffer + cnt, "%s ", policy_str[i]); |
| 832 | return cnt; |
| 833 | } |
| 834 | |
| 835 | module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy, |
| 836 | NULL, 0644); |
| 837 | |
| 838 | #ifdef CONFIG_PCIEASPM_DEBUG |
| 839 | static ssize_t link_state_show(struct device *dev, |
| 840 | struct device_attribute *attr, |
| 841 | char *buf) |
| 842 | { |
| 843 | struct pci_dev *pci_device = to_pci_dev(dev); |
| 844 | struct pcie_link_state *link_state = pci_device->link_state; |
| 845 | |
Kenji Kaneshige | 80bfdbe | 2009-05-13 12:12:43 +0900 | [diff] [blame] | 846 | return sprintf(buf, "%d\n", link_state->aspm_enabled); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 847 | } |
| 848 | |
| 849 | static ssize_t link_state_store(struct device *dev, |
| 850 | struct device_attribute *attr, |
| 851 | const char *buf, |
| 852 | size_t n) |
| 853 | { |
Kenji Kaneshige | 5aa6358 | 2009-05-13 12:17:44 +0900 | [diff] [blame] | 854 | struct pci_dev *pdev = to_pci_dev(dev); |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 855 | struct pcie_link_state *link, *root = pdev->link_state->root; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 856 | u32 val = buf[0] - '0', state = 0; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 857 | |
Naga Chumbalkar | bbfa306 | 2011-03-21 03:29:14 +0000 | [diff] [blame] | 858 | if (aspm_disabled) |
| 859 | return -EPERM; |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 860 | if (n < 1 || val > 3) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 861 | return -EINVAL; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 862 | |
Kenji Kaneshige | ac18018 | 2009-08-19 11:02:13 +0900 | [diff] [blame] | 863 | /* Convert requested state to ASPM state */ |
| 864 | if (val & PCIE_LINK_STATE_L0S) |
| 865 | state |= ASPM_STATE_L0S; |
| 866 | if (val & PCIE_LINK_STATE_L1) |
| 867 | state |= ASPM_STATE_L1; |
| 868 | |
Kenji Kaneshige | b7206cb | 2009-08-19 11:01:37 +0900 | [diff] [blame] | 869 | down_read(&pci_bus_sem); |
| 870 | mutex_lock(&aspm_lock); |
| 871 | list_for_each_entry(link, &link_list, sibling) { |
| 872 | if (link->root != root) |
| 873 | continue; |
| 874 | pcie_config_aspm_link(link, state); |
| 875 | } |
| 876 | mutex_unlock(&aspm_lock); |
| 877 | up_read(&pci_bus_sem); |
| 878 | return n; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 879 | } |
| 880 | |
| 881 | static ssize_t clk_ctl_show(struct device *dev, |
| 882 | struct device_attribute *attr, |
| 883 | char *buf) |
| 884 | { |
| 885 | struct pci_dev *pci_device = to_pci_dev(dev); |
| 886 | struct pcie_link_state *link_state = pci_device->link_state; |
| 887 | |
Kenji Kaneshige | 4d246e4 | 2009-05-13 12:15:38 +0900 | [diff] [blame] | 888 | return sprintf(buf, "%d\n", link_state->clkpm_enabled); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 889 | } |
| 890 | |
| 891 | static ssize_t clk_ctl_store(struct device *dev, |
| 892 | struct device_attribute *attr, |
| 893 | const char *buf, |
| 894 | size_t n) |
| 895 | { |
Kenji Kaneshige | 430842e | 2009-05-13 12:20:10 +0900 | [diff] [blame] | 896 | struct pci_dev *pdev = to_pci_dev(dev); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 897 | int state; |
| 898 | |
| 899 | if (n < 1) |
| 900 | return -EINVAL; |
| 901 | state = buf[0]-'0'; |
| 902 | |
| 903 | down_read(&pci_bus_sem); |
| 904 | mutex_lock(&aspm_lock); |
Kenji Kaneshige | 430842e | 2009-05-13 12:20:10 +0900 | [diff] [blame] | 905 | pcie_set_clkpm_nocheck(pdev->link_state, !!state); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 906 | mutex_unlock(&aspm_lock); |
| 907 | up_read(&pci_bus_sem); |
| 908 | |
| 909 | return n; |
| 910 | } |
| 911 | |
| 912 | static DEVICE_ATTR(link_state, 0644, link_state_show, link_state_store); |
| 913 | static DEVICE_ATTR(clk_ctl, 0644, clk_ctl_show, clk_ctl_store); |
| 914 | |
| 915 | static char power_group[] = "power"; |
| 916 | void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev) |
| 917 | { |
| 918 | struct pcie_link_state *link_state = pdev->link_state; |
| 919 | |
Kenji Kaneshige | 8b06477 | 2009-11-11 14:36:52 +0900 | [diff] [blame] | 920 | if (!pci_is_pcie(pdev) || |
| 921 | (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && |
| 922 | pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) || !link_state) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 923 | return; |
| 924 | |
Kenji Kaneshige | 80bfdbe | 2009-05-13 12:12:43 +0900 | [diff] [blame] | 925 | if (link_state->aspm_support) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 926 | sysfs_add_file_to_group(&pdev->dev.kobj, |
| 927 | &dev_attr_link_state.attr, power_group); |
Kenji Kaneshige | 4d246e4 | 2009-05-13 12:15:38 +0900 | [diff] [blame] | 928 | if (link_state->clkpm_capable) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 929 | sysfs_add_file_to_group(&pdev->dev.kobj, |
| 930 | &dev_attr_clk_ctl.attr, power_group); |
| 931 | } |
| 932 | |
| 933 | void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev) |
| 934 | { |
| 935 | struct pcie_link_state *link_state = pdev->link_state; |
| 936 | |
Kenji Kaneshige | 8b06477 | 2009-11-11 14:36:52 +0900 | [diff] [blame] | 937 | if (!pci_is_pcie(pdev) || |
| 938 | (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && |
| 939 | pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) || !link_state) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 940 | return; |
| 941 | |
Kenji Kaneshige | 80bfdbe | 2009-05-13 12:12:43 +0900 | [diff] [blame] | 942 | if (link_state->aspm_support) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 943 | sysfs_remove_file_from_group(&pdev->dev.kobj, |
| 944 | &dev_attr_link_state.attr, power_group); |
Kenji Kaneshige | 4d246e4 | 2009-05-13 12:15:38 +0900 | [diff] [blame] | 945 | if (link_state->clkpm_capable) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 946 | sysfs_remove_file_from_group(&pdev->dev.kobj, |
| 947 | &dev_attr_clk_ctl.attr, power_group); |
| 948 | } |
| 949 | #endif |
| 950 | |
| 951 | static int __init pcie_aspm_disable(char *str) |
| 952 | { |
Shaohua Li | d6d3857 | 2008-07-23 10:32:42 +0800 | [diff] [blame] | 953 | if (!strcmp(str, "off")) { |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 954 | aspm_policy = POLICY_DEFAULT; |
Shaohua Li | d6d3857 | 2008-07-23 10:32:42 +0800 | [diff] [blame] | 955 | aspm_disabled = 1; |
Rafael J. Wysocki | 8b8bae9 | 2011-03-05 13:21:51 +0100 | [diff] [blame] | 956 | aspm_support_enabled = false; |
Shaohua Li | d6d3857 | 2008-07-23 10:32:42 +0800 | [diff] [blame] | 957 | printk(KERN_INFO "PCIe ASPM is disabled\n"); |
| 958 | } else if (!strcmp(str, "force")) { |
| 959 | aspm_force = 1; |
Michael Witten | 8072ba1 | 2011-06-28 06:15:05 +0000 | [diff] [blame] | 960 | printk(KERN_INFO "PCIe ASPM is forcibly enabled\n"); |
Shaohua Li | d6d3857 | 2008-07-23 10:32:42 +0800 | [diff] [blame] | 961 | } |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 962 | return 1; |
| 963 | } |
| 964 | |
Shaohua Li | d6d3857 | 2008-07-23 10:32:42 +0800 | [diff] [blame] | 965 | __setup("pcie_aspm=", pcie_aspm_disable); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 966 | |
Shaohua Li | 5fde244 | 2008-07-23 10:32:24 +0800 | [diff] [blame] | 967 | void pcie_no_aspm(void) |
| 968 | { |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 969 | /* |
| 970 | * Disabling ASPM is intended to prevent the kernel from modifying |
| 971 | * existing hardware state, not to clear existing state. To that end: |
| 972 | * (a) set policy to POLICY_DEFAULT in order to avoid changing state |
| 973 | * (b) prevent userspace from changing policy |
| 974 | */ |
| 975 | if (!aspm_force) { |
| 976 | aspm_policy = POLICY_DEFAULT; |
Shaohua Li | d6d3857 | 2008-07-23 10:32:42 +0800 | [diff] [blame] | 977 | aspm_disabled = 1; |
Matthew Garrett | 3c07635 | 2011-11-10 16:38:33 -0500 | [diff] [blame] | 978 | } |
Shaohua Li | 5fde244 | 2008-07-23 10:32:24 +0800 | [diff] [blame] | 979 | } |
| 980 | |
Andrew Patterson | 3e1b160 | 2008-11-10 15:30:55 -0700 | [diff] [blame] | 981 | /** |
| 982 | * pcie_aspm_enabled - is PCIe ASPM enabled? |
| 983 | * |
| 984 | * Returns true if ASPM has not been disabled by the command-line option |
| 985 | * pcie_aspm=off. |
| 986 | **/ |
| 987 | int pcie_aspm_enabled(void) |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 988 | { |
Andrew Patterson | 3e1b160 | 2008-11-10 15:30:55 -0700 | [diff] [blame] | 989 | return !aspm_disabled; |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 990 | } |
Andrew Patterson | 3e1b160 | 2008-11-10 15:30:55 -0700 | [diff] [blame] | 991 | EXPORT_SYMBOL(pcie_aspm_enabled); |
Shaohua Li | 7d715a6 | 2008-02-25 09:46:41 +0800 | [diff] [blame] | 992 | |
Rafael J. Wysocki | 8b8bae9 | 2011-03-05 13:21:51 +0100 | [diff] [blame] | 993 | bool pcie_aspm_support_enabled(void) |
| 994 | { |
| 995 | return aspm_support_enabled; |
| 996 | } |
| 997 | EXPORT_SYMBOL(pcie_aspm_support_enabled); |