arch/arm/plat-s5p/sysmmu.c

   1 /* linux/arch/arm/plat-s5p/sysmmu.c
   2  *
   3  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
   4  *              http://www.samsung.com
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/io.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/platform_device.h>
  14
  15 #include <asm/pgtable.h>
  16
  17 #include <mach/map.h>
  18 #include <mach/regs-sysmmu.h>
  19 #include <plat/sysmmu.h>
  20
  21 #define CTRL_ENABLE     0x5
  22 #define CTRL_BLOCK      0x7
  23 #define CTRL_DISABLE    0x0
  24
  25 static struct device *dev;
  26
  27 static unsigned short fault_reg_offset[SYSMMU_FAULTS_NUM] = {
  28         S5P_PAGE_FAULT_ADDR,
  29         S5P_AR_FAULT_ADDR,
  30         S5P_AW_FAULT_ADDR,
  31         S5P_DEFAULT_SLAVE_ADDR,
  32         S5P_AR_FAULT_ADDR,
  33         S5P_AR_FAULT_ADDR,
  34         S5P_AW_FAULT_ADDR,
  35         S5P_AW_FAULT_ADDR
  36 };
  37
  38 static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
  39         "PAGE FAULT",
  40         "AR MULTI-HIT FAULT",
  41         "AW MULTI-HIT FAULT",
  42         "BUS ERROR",
  43         "AR SECURITY PROTECTION FAULT",
  44         "AR ACCESS PROTECTION FAULT",
  45         "AW SECURITY PROTECTION FAULT",
  46         "AW ACCESS PROTECTION FAULT"
  47 };
  48
  49 static int (*fault_handlers[S5P_SYSMMU_TOTAL_IPNUM])(
  50                 enum S5P_SYSMMU_INTERRUPT_TYPE itype,
  51                 unsigned long pgtable_base,
  52                 unsigned long fault_addr);
  53
  54 /*
  55  * If adjacent 2 bits are true, the system MMU is enabled.
  56  * The system MMU is disabled, otherwise.
  57  */
  58 static unsigned long sysmmu_states;
  59
  60 static inline void set_sysmmu_active(sysmmu_ips ips)
  61 {
  62         sysmmu_states |= 3 << (ips * 2);
  63 }
  64
  65 static inline void set_sysmmu_inactive(sysmmu_ips ips)
  66 {
  67         sysmmu_states &= ~(3 << (ips * 2));
  68 }
  69
  70 static inline int is_sysmmu_active(sysmmu_ips ips)
  71 {
  72         return sysmmu_states & (3 << (ips * 2));
  73 }
  74
  75 static void __iomem *sysmmusfrs[S5P_SYSMMU_TOTAL_IPNUM];
  76
  77 static inline void sysmmu_block(sysmmu_ips ips)
  78 {
  79         __raw_writel(CTRL_BLOCK, sysmmusfrs[ips] + S5P_MMU_CTRL);
  80         dev_dbg(dev, "%s is blocked.\n", sysmmu_ips_name[ips]);
  81 }
  82
  83 static inline void sysmmu_unblock(sysmmu_ips ips)
  84 {
  85         __raw_writel(CTRL_ENABLE, sysmmusfrs[ips] + S5P_MMU_CTRL);
  86         dev_dbg(dev, "%s is unblocked.\n", sysmmu_ips_name[ips]);
  87 }
  88
  89 static inline void __sysmmu_tlb_invalidate(sysmmu_ips ips)
  90 {
  91         __raw_writel(0x1, sysmmusfrs[ips] + S5P_MMU_FLUSH);
  92         dev_dbg(dev, "TLB of %s is invalidated.\n", sysmmu_ips_name[ips]);
  93 }
  94
  95 static inline void __sysmmu_set_ptbase(sysmmu_ips ips, unsigned long pgd)
  96 {
  97         if (unlikely(pgd == 0)) {
  98                 pgd = (unsigned long)ZERO_PAGE(0);
  99                 __raw_writel(0x20, sysmmusfrs[ips] + S5P_MMU_CFG); /* 4KB LV1 */
 100         } else {
 101                 __raw_writel(0x0, sysmmusfrs[ips] + S5P_MMU_CFG); /* 16KB LV1 */
 102         }
 103
 104         __raw_writel(pgd, sysmmusfrs[ips] + S5P_PT_BASE_ADDR);
 105
 106         dev_dbg(dev, "Page table base of %s is initialized with 0x%08lX.\n",
 107                                                 sysmmu_ips_name[ips], pgd);
 108         __sysmmu_tlb_invalidate(ips);
 109 }
 110
 111 void sysmmu_set_fault_handler(sysmmu_ips ips,
 112                         int (*handler)(enum S5P_SYSMMU_INTERRUPT_TYPE itype,
 113                                         unsigned long pgtable_base,
 114                                         unsigned long fault_addr))
 115 {
 116         BUG_ON(!((ips >= SYSMMU_MDMA) && (ips < S5P_SYSMMU_TOTAL_IPNUM)));
 117         fault_handlers[ips] = handler;
 118 }
 119
 120 static irqreturn_t s5p_sysmmu_irq(int irq, void *dev_id)
 121 {
 122         /* SYSMMU is in blocked when interrupt occurred. */
 123         unsigned long base = 0;
 124         sysmmu_ips ips = (sysmmu_ips)dev_id;
 125         enum S5P_SYSMMU_INTERRUPT_TYPE itype;
 126
 127         itype = (enum S5P_SYSMMU_INTERRUPT_TYPE)
 128                 __ffs(__raw_readl(sysmmusfrs[ips] + S5P_INT_STATUS));
 129
 130         BUG_ON(!((itype >= 0) && (itype < 8)));
 131
 132         dev_alert(dev, "%s occurred by %s.\n", sysmmu_fault_name[itype],
 133                                                         sysmmu_ips_name[ips]);
 134
 135         if (fault_handlers[ips]) {
 136                 unsigned long addr;
 137
 138                 base = __raw_readl(sysmmusfrs[ips] + S5P_PT_BASE_ADDR);
 139                 addr = __raw_readl(sysmmusfrs[ips] + fault_reg_offset[itype]);
 140
 141                 if (fault_handlers[ips](itype, base, addr)) {
 142                         __raw_writel(1 << itype,
 143                                         sysmmusfrs[ips] + S5P_INT_CLEAR);
 144                         dev_notice(dev, "%s from %s is resolved."
 145                                         " Retrying translation.\n",
 146                                 sysmmu_fault_name[itype], sysmmu_ips_name[ips]);
 147                 } else {
 148                         base = 0;
 149                 }
 150         }
 151
 152         sysmmu_unblock(ips);
 153
 154         if (!base)
 155                 dev_notice(dev, "%s from %s is not handled.\n",
 156                         sysmmu_fault_name[itype], sysmmu_ips_name[ips]);
 157
 158         return IRQ_HANDLED;
 159 }
 160
 161 void s5p_sysmmu_set_tablebase_pgd(sysmmu_ips ips, unsigned long pgd)
 162 {
 163         if (is_sysmmu_active(ips)) {
 164                 sysmmu_block(ips);
 165                 __sysmmu_set_ptbase(ips, pgd);
 166                 sysmmu_unblock(ips);
 167         } else {
 168                 dev_dbg(dev, "%s is disabled. "
 169                         "Skipping initializing page table base.\n",
 170                                                 sysmmu_ips_name[ips]);
 171         }
 172 }
 173
 174 void s5p_sysmmu_enable(sysmmu_ips ips, unsigned long pgd)
 175 {
 176         if (!is_sysmmu_active(ips)) {
 177                 sysmmu_clk_enable(ips);
 178
 179                 __sysmmu_set_ptbase(ips, pgd);
 180
 181                 __raw_writel(CTRL_ENABLE, sysmmusfrs[ips] + S5P_MMU_CTRL);
 182
 183                 set_sysmmu_active(ips);
 184                 dev_dbg(dev, "%s is enabled.\n", sysmmu_ips_name[ips]);
 185         } else {
 186                 dev_dbg(dev, "%s is already enabled.\n", sysmmu_ips_name[ips]);
 187         }
 188 }
 189
 190 void s5p_sysmmu_disable(sysmmu_ips ips)
 191 {
 192         if (is_sysmmu_active(ips)) {
 193                 __raw_writel(CTRL_DISABLE, sysmmusfrs[ips] + S5P_MMU_CTRL);
 194                 set_sysmmu_inactive(ips);
 195                 sysmmu_clk_disable(ips);
 196                 dev_dbg(dev, "%s is disabled.\n", sysmmu_ips_name[ips]);
 197         } else {
 198                 dev_dbg(dev, "%s is already disabled.\n", sysmmu_ips_name[ips]);
 199         }
 200 }
 201
 202 void s5p_sysmmu_tlb_invalidate(sysmmu_ips ips)
 203 {
 204         if (is_sysmmu_active(ips)) {
 205                 sysmmu_block(ips);
 206                 __sysmmu_tlb_invalidate(ips);
 207                 sysmmu_unblock(ips);
 208         } else {
 209                 dev_dbg(dev, "%s is disabled. "
 210                         "Skipping invalidating TLB.\n", sysmmu_ips_name[ips]);
 211         }
 212 }
 213
 214 static int s5p_sysmmu_probe(struct platform_device *pdev)
 215 {
 216         int i, ret;
 217         struct resource *res, *mem;
 218
 219         dev = &pdev->dev;
 220
 221         for (i = 0; i < S5P_SYSMMU_TOTAL_IPNUM; i++) {
 222                 int irq;
 223
 224                 sysmmu_clk_init(dev, i);
 225                 sysmmu_clk_disable(i);
 226
 227                 res = platform_get_resource(pdev, IORESOURCE_MEM, i);
 228                 if (!res) {
 229                         dev_err(dev, "Failed to get the resource of %s.\n",
 230                                                         sysmmu_ips_name[i]);
 231                         ret = -ENODEV;
 232                         goto err_res;
 233                 }
 234
 235                 mem = request_mem_region(res->start,
 236                                 ((res->end) - (res->start)) + 1, pdev->name);
 237                 if (!mem) {
 238                         dev_err(dev, "Failed to request the memory region of %s.\n",
 239                                                         sysmmu_ips_name[i]);
 240                         ret = -EBUSY;
 241                         goto err_res;
 242                 }
 243
 244                 sysmmusfrs[i] = ioremap(res->start, res->end - res->start + 1);
 245                 if (!sysmmusfrs[i]) {
 246                         dev_err(dev, "Failed to ioremap() for %s.\n",
 247                                                         sysmmu_ips_name[i]);
 248                         ret = -ENXIO;
 249                         goto err_reg;
 250                 }
 251
 252                 irq = platform_get_irq(pdev, i);
 253                 if (irq <= 0) {
 254                         dev_err(dev, "Failed to get the IRQ resource of %s.\n",
 255                                                         sysmmu_ips_name[i]);
 256                         ret = -ENOENT;
 257                         goto err_map;
 258                 }
 259
 260                 if (request_irq(irq, s5p_sysmmu_irq, IRQF_DISABLED,
 261                                                 pdev->name, (void *)i)) {
 262                         dev_err(dev, "Failed to request IRQ for %s.\n",
 263                                                         sysmmu_ips_name[i]);
 264                         ret = -ENOENT;
 265                         goto err_map;
 266                 }
 267         }
 268
 269         return 0;
 270
 271 err_map:
 272         iounmap(sysmmusfrs[i]);
 273 err_reg:
 274         release_mem_region(mem->start, resource_size(mem));
 275 err_res:
 276         return ret;
 277 }
 278
 279 static int s5p_sysmmu_remove(struct platform_device *pdev)
 280 {
 281         return 0;
 282 }
 283 int s5p_sysmmu_runtime_suspend(struct device *dev)
 284 {
 285         return 0;
 286 }
 287
 288 int s5p_sysmmu_runtime_resume(struct device *dev)
 289 {
 290         return 0;
 291 }
 292
 293 const struct dev_pm_ops s5p_sysmmu_pm_ops = {
 294         .runtime_suspend        = s5p_sysmmu_runtime_suspend,
 295         .runtime_resume         = s5p_sysmmu_runtime_resume,
 296 };
 297
 298 static struct platform_driver s5p_sysmmu_driver = {
 299         .probe          = s5p_sysmmu_probe,
 300         .remove         = s5p_sysmmu_remove,
 301         .driver         = {
 302                 .owner          = THIS_MODULE,
 303                 .name           = "s5p-sysmmu",
 304                 .pm             = &s5p_sysmmu_pm_ops,
 305         }
 306 };
 307
 308 static int __init s5p_sysmmu_init(void)
 309 {
 310         return platform_driver_register(&s5p_sysmmu_driver);
 311 }
 312 arch_initcall(s5p_sysmmu_init);