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Marcelo Roberto Jimenezb080ac82010-12-16 21:34:51 +01001/*
2 * linux/arch/arm/mach-sa1100/pci-nanoengine.c
3 *
4 * PCI functions for BSE nanoEngine PCI
5 *
6 * Copyright (C) 2010 Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22#include <linux/kernel.h>
23#include <linux/irq.h>
24#include <linux/pci.h>
25#include <linux/spinlock.h>
26
27#include <asm/mach/pci.h>
28#include <asm/mach-types.h>
29
30#include <mach/nanoengine.h>
31
32static DEFINE_SPINLOCK(nano_lock);
33
34static int nanoengine_get_pci_address(struct pci_bus *bus,
35 unsigned int devfn, int where, unsigned long *address)
36{
37 int ret = PCIBIOS_DEVICE_NOT_FOUND;
38 unsigned int busnr = bus->number;
39
40 *address = NANO_PCI_CONFIG_SPACE_VIRT +
41 ((bus->number << 16) | (devfn << 8) | (where & ~3));
42
43 ret = (busnr > 255 || devfn > 255 || where > 255) ?
44 PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
45
46 return ret;
47}
48
49static int nanoengine_read_config(struct pci_bus *bus, unsigned int devfn, int where,
50 int size, u32 *val)
51{
52 int ret;
53 unsigned long address;
54 unsigned long flags;
55 u32 v;
56
57 /* nanoEngine PCI bridge does not return -1 for a non-existing
58 * device. We must fake the answer. We know that the only valid
59 * device is device zero at bus 0, which is the network chip. */
60 if (bus->number != 0 || (devfn >> 3) != 0) {
61 v = -1;
62 nanoengine_get_pci_address(bus, devfn, where, &address);
63 goto exit_function;
64 }
65
66 spin_lock_irqsave(&nano_lock, flags);
67
68 ret = nanoengine_get_pci_address(bus, devfn, where, &address);
69 if (ret != PCIBIOS_SUCCESSFUL)
70 return ret;
71 v = __raw_readl(address);
72
73 spin_unlock_irqrestore(&nano_lock, flags);
74
75 v >>= ((where & 3) * 8);
76 v &= (unsigned long)(-1) >> ((4 - size) * 8);
77
78exit_function:
79 *val = v;
80 return PCIBIOS_SUCCESSFUL;
81}
82
83static int nanoengine_write_config(struct pci_bus *bus, unsigned int devfn, int where,
84 int size, u32 val)
85{
86 int ret;
87 unsigned long address;
88 unsigned long flags;
89 unsigned shift;
90 u32 v;
91
92 shift = (where & 3) * 8;
93
94 spin_lock_irqsave(&nano_lock, flags);
95
96 ret = nanoengine_get_pci_address(bus, devfn, where, &address);
97 if (ret != PCIBIOS_SUCCESSFUL)
98 return ret;
99 v = __raw_readl(address);
100 switch (size) {
101 case 1:
102 v &= ~(0xFF << shift);
103 v |= val << shift;
104 break;
105 case 2:
106 v &= ~(0xFFFF << shift);
107 v |= val << shift;
108 break;
109 case 4:
110 v = val;
111 break;
112 }
113 __raw_writel(v, address);
114
115 spin_unlock_irqrestore(&nano_lock, flags);
116
117 return PCIBIOS_SUCCESSFUL;
118}
119
120static struct pci_ops pci_nano_ops = {
121 .read = nanoengine_read_config,
122 .write = nanoengine_write_config,
123};
124
125static int __init pci_nanoengine_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
126{
127 return NANOENGINE_IRQ_GPIO_PCI;
128}
129
130struct pci_bus * __init pci_nanoengine_scan_bus(int nr, struct pci_sys_data *sys)
131{
132 return pci_scan_bus(sys->busnr, &pci_nano_ops, sys);
133}
134
135static struct resource pci_io_ports = {
136 .name = "PCI IO",
137 .start = 0x400,
138 .end = 0x7FF,
139 .flags = IORESOURCE_IO,
140};
141
142static struct resource pci_non_prefetchable_memory = {
143 .name = "PCI non-prefetchable",
144 .start = NANO_PCI_MEM_RW_PHYS,
145 /* nanoEngine documentation says there is a 1 Megabyte window here,
146 * but PCI reports just 128 + 8 kbytes. */
147 .end = NANO_PCI_MEM_RW_PHYS + NANO_PCI_MEM_RW_SIZE - 1,
148/* .end = NANO_PCI_MEM_RW_PHYS + SZ_128K + SZ_8K - 1,*/
149 .flags = IORESOURCE_MEM,
150};
151
152/*
153 * nanoEngine PCI reports 1 Megabyte of prefetchable memory, but it
154 * overlaps with previously defined memory.
155 *
156 * Here is what happens:
157 *
158# dmesg
159...
160pci 0000:00:00.0: [8086:1209] type 0 class 0x000200
161pci 0000:00:00.0: reg 10: [mem 0x00021000-0x00021fff]
162pci 0000:00:00.0: reg 14: [io 0x0000-0x003f]
163pci 0000:00:00.0: reg 18: [mem 0x00000000-0x0001ffff]
164pci 0000:00:00.0: reg 30: [mem 0x00000000-0x000fffff pref]
165pci 0000:00:00.0: supports D1 D2
166pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot
167pci 0000:00:00.0: PME# disabled
168PCI: bus0: Fast back to back transfers enabled
169pci 0000:00:00.0: BAR 6: can't assign mem pref (size 0x100000)
170pci 0000:00:00.0: BAR 2: assigned [mem 0x18600000-0x1861ffff]
171pci 0000:00:00.0: BAR 2: set to [mem 0x18600000-0x1861ffff] (PCI address [0x0-0x1ffff])
172pci 0000:00:00.0: BAR 0: assigned [mem 0x18620000-0x18620fff]
173pci 0000:00:00.0: BAR 0: set to [mem 0x18620000-0x18620fff] (PCI address [0x20000-0x20fff])
174pci 0000:00:00.0: BAR 1: assigned [io 0x0400-0x043f]
175pci 0000:00:00.0: BAR 1: set to [io 0x0400-0x043f] (PCI address [0x0-0x3f])
176 *
177 * On the other hand, if we do not request the prefetchable memory resource,
178 * linux will alloc it first and the two non-prefetchable memory areas that
179 * are our real interest will not be mapped. So we choose to map it to an
180 * unused area. It gets recognized as expansion ROM, but becomes disabled.
181 *
182 * Here is what happens then:
183 *
184# dmesg
185...
186pci 0000:00:00.0: [8086:1209] type 0 class 0x000200
187pci 0000:00:00.0: reg 10: [mem 0x00021000-0x00021fff]
188pci 0000:00:00.0: reg 14: [io 0x0000-0x003f]
189pci 0000:00:00.0: reg 18: [mem 0x00000000-0x0001ffff]
190pci 0000:00:00.0: reg 30: [mem 0x00000000-0x000fffff pref]
191pci 0000:00:00.0: supports D1 D2
192pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot
193pci 0000:00:00.0: PME# disabled
194PCI: bus0: Fast back to back transfers enabled
195pci 0000:00:00.0: BAR 6: assigned [mem 0x78000000-0x780fffff pref]
196pci 0000:00:00.0: BAR 2: assigned [mem 0x18600000-0x1861ffff]
197pci 0000:00:00.0: BAR 2: set to [mem 0x18600000-0x1861ffff] (PCI address [0x0-0x1ffff])
198pci 0000:00:00.0: BAR 0: assigned [mem 0x18620000-0x18620fff]
199pci 0000:00:00.0: BAR 0: set to [mem 0x18620000-0x18620fff] (PCI address [0x20000-0x20fff])
200pci 0000:00:00.0: BAR 1: assigned [io 0x0400-0x043f]
201pci 0000:00:00.0: BAR 1: set to [io 0x0400-0x043f] (PCI address [0x0-0x3f])
202
203# lspci -vv -s 0000:00:00.0
20400:00.0 Class 0200: Device 8086:1209 (rev 09)
205 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr+ Stepping- SERR+ FastB2B- DisINTx-
206 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR+ <PERR+ INTx-
207 Latency: 0 (2000ns min, 14000ns max), Cache Line Size: 32 bytes
208 Interrupt: pin A routed to IRQ 0
209 Region 0: Memory at 18620000 (32-bit, non-prefetchable) [size=4K]
210 Region 1: I/O ports at 0400 [size=64]
211 Region 2: [virtual] Memory at 18600000 (32-bit, non-prefetchable) [size=128K]
212 [virtual] Expansion ROM at 78000000 [disabled] [size=1M]
213 Capabilities: [dc] Power Management version 2
214 Flags: PMEClk- DSI+ D1+ D2+ AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold-)
215 Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=2 PME-
216 Kernel driver in use: e100
217 Kernel modules: e100
218 *
219 */
220static struct resource pci_prefetchable_memory = {
221 .name = "PCI prefetchable",
222 .start = 0x78000000,
223 .end = 0x78000000 + NANO_PCI_MEM_RW_SIZE - 1,
224 .flags = IORESOURCE_MEM | IORESOURCE_PREFETCH,
225};
226
227static int __init pci_nanoengine_setup_resources(struct resource **resource)
228{
229 if (request_resource(&ioport_resource, &pci_io_ports)) {
230 printk(KERN_ERR "PCI: unable to allocate io port region\n");
231 return -EBUSY;
232 }
233 if (request_resource(&iomem_resource, &pci_non_prefetchable_memory)) {
234 release_resource(&pci_io_ports);
235 printk(KERN_ERR "PCI: unable to allocate non prefetchable\n");
236 return -EBUSY;
237 }
238 if (request_resource(&iomem_resource, &pci_prefetchable_memory)) {
239 release_resource(&pci_io_ports);
240 release_resource(&pci_non_prefetchable_memory);
241 printk(KERN_ERR "PCI: unable to allocate prefetchable\n");
242 return -EBUSY;
243 }
244 resource[0] = &pci_io_ports;
245 resource[1] = &pci_non_prefetchable_memory;
246 resource[2] = &pci_prefetchable_memory;
247
248 return 1;
249}
250
251int __init pci_nanoengine_setup(int nr, struct pci_sys_data *sys)
252{
253 int ret = 0;
254
255 if (nr == 0) {
256 sys->mem_offset = NANO_PCI_MEM_RW_PHYS;
257 sys->io_offset = 0x400;
258 ret = pci_nanoengine_setup_resources(sys->resource);
259 /* Enable alternate memory bus master mode, see
260 * "Intel StrongARM SA1110 Developer's Manual",
261 * section 10.8, "Alternate Memory Bus Master Mode". */
262 GPDR = (GPDR & ~GPIO_MBREQ) | GPIO_MBGNT;
263 GAFR |= GPIO_MBGNT | GPIO_MBREQ;
264 TUCR |= TUCR_MBGPIO;
265 }
266
267 return ret;
268}
269
270static struct hw_pci nanoengine_pci __initdata = {
271 .map_irq = pci_nanoengine_map_irq,
272 .nr_controllers = 1,
273 .scan = pci_nanoengine_scan_bus,
274 .setup = pci_nanoengine_setup,
275};
276
277static int __init nanoengine_pci_init(void)
278{
279 if (machine_is_nanoengine())
280 pci_common_init(&nanoengine_pci);
281 return 0;
282}
283
284subsys_initcall(nanoengine_pci_init);