Linus Walleij | b0afd44 | 2016-01-26 11:58:07 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Versatile OF physmap driver add-on |
| 3 | * |
| 4 | * Copyright (c) 2016, Linaro Limited |
| 5 | * Author: Linus Walleij <linus.walleij@linaro.org> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License as |
| 9 | * published by the Free Software Foundation; either version 2 of |
| 10 | * the License, or (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| 20 | * MA 02111-1307 USA |
| 21 | */ |
Arnd Bergmann | c5f9d6b | 2016-04-26 01:01:40 +0200 | [diff] [blame] | 22 | #include <linux/export.h> |
Linus Walleij | b0afd44 | 2016-01-26 11:58:07 +0100 | [diff] [blame] | 23 | #include <linux/io.h> |
| 24 | #include <linux/of.h> |
| 25 | #include <linux/of_address.h> |
| 26 | #include <linux/of_device.h> |
| 27 | #include <linux/mtd/map.h> |
| 28 | #include <linux/mfd/syscon.h> |
| 29 | #include <linux/regmap.h> |
| 30 | #include <linux/bitops.h> |
| 31 | #include "physmap_of_versatile.h" |
| 32 | |
| 33 | static struct regmap *syscon_regmap; |
| 34 | |
| 35 | enum versatile_flashprot { |
| 36 | INTEGRATOR_AP_FLASHPROT, |
| 37 | INTEGRATOR_CP_FLASHPROT, |
| 38 | VERSATILE_FLASHPROT, |
| 39 | REALVIEW_FLASHPROT, |
| 40 | }; |
| 41 | |
| 42 | static const struct of_device_id syscon_match[] = { |
| 43 | { |
| 44 | .compatible = "arm,integrator-ap-syscon", |
| 45 | .data = (void *)INTEGRATOR_AP_FLASHPROT, |
| 46 | }, |
| 47 | { |
| 48 | .compatible = "arm,integrator-cp-syscon", |
| 49 | .data = (void *)INTEGRATOR_CP_FLASHPROT, |
| 50 | }, |
| 51 | { |
| 52 | .compatible = "arm,core-module-versatile", |
| 53 | .data = (void *)VERSATILE_FLASHPROT, |
| 54 | }, |
| 55 | { |
| 56 | .compatible = "arm,realview-eb-syscon", |
| 57 | .data = (void *)REALVIEW_FLASHPROT, |
| 58 | }, |
| 59 | { |
| 60 | .compatible = "arm,realview-pb1176-syscon", |
| 61 | .data = (void *)REALVIEW_FLASHPROT, |
| 62 | }, |
| 63 | { |
| 64 | .compatible = "arm,realview-pb11mp-syscon", |
| 65 | .data = (void *)REALVIEW_FLASHPROT, |
| 66 | }, |
| 67 | { |
| 68 | .compatible = "arm,realview-pba8-syscon", |
| 69 | .data = (void *)REALVIEW_FLASHPROT, |
| 70 | }, |
| 71 | { |
| 72 | .compatible = "arm,realview-pbx-syscon", |
| 73 | .data = (void *)REALVIEW_FLASHPROT, |
| 74 | }, |
| 75 | {}, |
| 76 | }; |
| 77 | |
| 78 | /* |
| 79 | * Flash protection handling for the Integrator/AP |
| 80 | */ |
| 81 | #define INTEGRATOR_SC_CTRLS_OFFSET 0x08 |
| 82 | #define INTEGRATOR_SC_CTRLC_OFFSET 0x0C |
| 83 | #define INTEGRATOR_SC_CTRL_FLVPPEN BIT(1) |
| 84 | #define INTEGRATOR_SC_CTRL_FLWP BIT(2) |
| 85 | |
| 86 | #define INTEGRATOR_EBI_CSR1_OFFSET 0x04 |
| 87 | /* The manual says bit 2, the code says bit 3, trust the code */ |
| 88 | #define INTEGRATOR_EBI_WRITE_ENABLE BIT(3) |
| 89 | #define INTEGRATOR_EBI_LOCK_OFFSET 0x20 |
| 90 | #define INTEGRATOR_EBI_LOCK_VAL 0xA05F |
| 91 | |
| 92 | static const struct of_device_id ebi_match[] = { |
| 93 | { .compatible = "arm,external-bus-interface"}, |
| 94 | { }, |
| 95 | }; |
| 96 | |
| 97 | static int ap_flash_init(struct platform_device *pdev) |
| 98 | { |
| 99 | struct device_node *ebi; |
| 100 | static void __iomem *ebi_base; |
| 101 | u32 val; |
| 102 | int ret; |
| 103 | |
| 104 | /* Look up the EBI */ |
| 105 | ebi = of_find_matching_node(NULL, ebi_match); |
| 106 | if (!ebi) { |
| 107 | return -ENODEV; |
| 108 | } |
| 109 | ebi_base = of_iomap(ebi, 0); |
| 110 | if (!ebi_base) |
| 111 | return -ENODEV; |
| 112 | |
| 113 | /* Clear VPP and write protection bits */ |
| 114 | ret = regmap_write(syscon_regmap, |
| 115 | INTEGRATOR_SC_CTRLC_OFFSET, |
| 116 | INTEGRATOR_SC_CTRL_FLVPPEN | INTEGRATOR_SC_CTRL_FLWP); |
| 117 | if (ret) |
| 118 | dev_err(&pdev->dev, "error clearing Integrator VPP/WP\n"); |
| 119 | |
| 120 | /* Unlock the EBI */ |
| 121 | writel(INTEGRATOR_EBI_LOCK_VAL, ebi_base + INTEGRATOR_EBI_LOCK_OFFSET); |
| 122 | |
| 123 | /* Enable write cycles on the EBI, CSR1 (flash) */ |
| 124 | val = readl(ebi_base + INTEGRATOR_EBI_CSR1_OFFSET); |
| 125 | val |= INTEGRATOR_EBI_WRITE_ENABLE; |
| 126 | writel(val, ebi_base + INTEGRATOR_EBI_CSR1_OFFSET); |
| 127 | |
| 128 | /* Lock the EBI again */ |
| 129 | writel(0, ebi_base + INTEGRATOR_EBI_LOCK_OFFSET); |
| 130 | iounmap(ebi_base); |
| 131 | |
| 132 | return 0; |
| 133 | } |
| 134 | |
| 135 | static void ap_flash_set_vpp(struct map_info *map, int on) |
| 136 | { |
| 137 | int ret; |
| 138 | |
| 139 | if (on) { |
| 140 | ret = regmap_write(syscon_regmap, |
| 141 | INTEGRATOR_SC_CTRLS_OFFSET, |
| 142 | INTEGRATOR_SC_CTRL_FLVPPEN | INTEGRATOR_SC_CTRL_FLWP); |
| 143 | if (ret) |
| 144 | pr_err("error enabling AP VPP\n"); |
| 145 | } else { |
| 146 | ret = regmap_write(syscon_regmap, |
| 147 | INTEGRATOR_SC_CTRLC_OFFSET, |
| 148 | INTEGRATOR_SC_CTRL_FLVPPEN | INTEGRATOR_SC_CTRL_FLWP); |
| 149 | if (ret) |
| 150 | pr_err("error disabling AP VPP\n"); |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | /* |
| 155 | * Flash protection handling for the Integrator/CP |
| 156 | */ |
| 157 | |
| 158 | #define INTCP_FLASHPROG_OFFSET 0x04 |
| 159 | #define CINTEGRATOR_FLVPPEN BIT(0) |
| 160 | #define CINTEGRATOR_FLWREN BIT(1) |
| 161 | #define CINTEGRATOR_FLMASK BIT(0)|BIT(1) |
| 162 | |
| 163 | static void cp_flash_set_vpp(struct map_info *map, int on) |
| 164 | { |
| 165 | int ret; |
| 166 | |
| 167 | if (on) { |
| 168 | ret = regmap_update_bits(syscon_regmap, |
| 169 | INTCP_FLASHPROG_OFFSET, |
| 170 | CINTEGRATOR_FLMASK, |
| 171 | CINTEGRATOR_FLVPPEN | CINTEGRATOR_FLWREN); |
| 172 | if (ret) |
| 173 | pr_err("error setting CP VPP\n"); |
| 174 | } else { |
| 175 | ret = regmap_update_bits(syscon_regmap, |
| 176 | INTCP_FLASHPROG_OFFSET, |
| 177 | CINTEGRATOR_FLMASK, |
| 178 | 0); |
| 179 | if (ret) |
| 180 | pr_err("error setting CP VPP\n"); |
| 181 | } |
| 182 | } |
| 183 | |
| 184 | /* |
| 185 | * Flash protection handling for the Versatiles and RealViews |
| 186 | */ |
| 187 | |
| 188 | #define VERSATILE_SYS_FLASH_OFFSET 0x4C |
| 189 | |
| 190 | static void versatile_flash_set_vpp(struct map_info *map, int on) |
| 191 | { |
| 192 | int ret; |
| 193 | |
| 194 | ret = regmap_update_bits(syscon_regmap, VERSATILE_SYS_FLASH_OFFSET, |
| 195 | 0x01, !!on); |
| 196 | if (ret) |
| 197 | pr_err("error setting Versatile VPP\n"); |
| 198 | } |
| 199 | |
| 200 | int of_flash_probe_versatile(struct platform_device *pdev, |
| 201 | struct device_node *np, |
| 202 | struct map_info *map) |
| 203 | { |
| 204 | struct device_node *sysnp; |
| 205 | const struct of_device_id *devid; |
| 206 | struct regmap *rmap; |
| 207 | static enum versatile_flashprot versatile_flashprot; |
| 208 | int ret; |
| 209 | |
| 210 | /* Not all flash chips use this protection line */ |
| 211 | if (!of_device_is_compatible(np, "arm,versatile-flash")) |
| 212 | return 0; |
| 213 | |
| 214 | /* For first chip probed, look up the syscon regmap */ |
| 215 | if (!syscon_regmap) { |
| 216 | sysnp = of_find_matching_node_and_match(NULL, |
| 217 | syscon_match, |
| 218 | &devid); |
| 219 | if (!sysnp) |
| 220 | return -ENODEV; |
| 221 | |
| 222 | versatile_flashprot = (enum versatile_flashprot)devid->data; |
| 223 | rmap = syscon_node_to_regmap(sysnp); |
| 224 | if (IS_ERR(rmap)) |
| 225 | return PTR_ERR(rmap); |
| 226 | |
| 227 | syscon_regmap = rmap; |
| 228 | } |
| 229 | |
| 230 | switch (versatile_flashprot) { |
| 231 | case INTEGRATOR_AP_FLASHPROT: |
| 232 | ret = ap_flash_init(pdev); |
| 233 | if (ret) |
| 234 | return ret; |
| 235 | map->set_vpp = ap_flash_set_vpp; |
| 236 | dev_info(&pdev->dev, "Integrator/AP flash protection\n"); |
| 237 | break; |
| 238 | case INTEGRATOR_CP_FLASHPROT: |
| 239 | map->set_vpp = cp_flash_set_vpp; |
| 240 | dev_info(&pdev->dev, "Integrator/CP flash protection\n"); |
| 241 | break; |
| 242 | case VERSATILE_FLASHPROT: |
| 243 | case REALVIEW_FLASHPROT: |
| 244 | map->set_vpp = versatile_flash_set_vpp; |
| 245 | dev_info(&pdev->dev, "versatile/realview flash protection\n"); |
| 246 | break; |
| 247 | default: |
| 248 | dev_info(&pdev->dev, "device marked as Versatile flash " |
| 249 | "but no system controller was found\n"); |
| 250 | break; |
| 251 | } |
| 252 | |
| 253 | return 0; |
| 254 | } |
Arnd Bergmann | c5f9d6b | 2016-04-26 01:01:40 +0200 | [diff] [blame] | 255 | EXPORT_SYMBOL_GPL(of_flash_probe_versatile); |