arch/csky/mm/tcm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include <linux/highmem.h>
   4 #include <linux/genalloc.h>
   5 #include <asm/tlbflush.h>
   6 #include <asm/fixmap.h>
   7
   8 #if (CONFIG_ITCM_RAM_BASE == 0xffffffff)
   9 #error "You should define ITCM_RAM_BASE"
  10 #endif
  11
  12 #ifdef CONFIG_HAVE_DTCM
  13 #if (CONFIG_DTCM_RAM_BASE == 0xffffffff)
  14 #error "You should define DTCM_RAM_BASE"
  15 #endif
  16
  17 #if (CONFIG_DTCM_RAM_BASE == CONFIG_ITCM_RAM_BASE)
  18 #error "You should define correct DTCM_RAM_BASE"
  19 #endif
  20 #endif
  21
  22 extern char __tcm_start, __tcm_end, __dtcm_start;
  23
  24 static struct gen_pool *tcm_pool;
  25
  26 static void __init tcm_mapping_init(void)
  27 {
  28         pte_t *tcm_pte;
  29         unsigned long vaddr, paddr;
  30         int i;
  31
  32         paddr = CONFIG_ITCM_RAM_BASE;
  33
  34         if (pfn_valid(PFN_DOWN(CONFIG_ITCM_RAM_BASE)))
  35                 goto panic;
  36
  37 #ifndef CONFIG_HAVE_DTCM
  38         for (i = 0; i < TCM_NR_PAGES; i++) {
  39 #else
  40         for (i = 0; i < CONFIG_ITCM_NR_PAGES; i++) {
  41 #endif
  42                 vaddr = __fix_to_virt(FIX_TCM - i);
  43
  44                 tcm_pte =
  45                         pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
  46
  47                 set_pte(tcm_pte, pfn_pte(__phys_to_pfn(paddr), PAGE_KERNEL));
  48
  49                 flush_tlb_one(vaddr);
  50
  51                 paddr = paddr + PAGE_SIZE;
  52         }
  53
  54 #ifdef CONFIG_HAVE_DTCM
  55         if (pfn_valid(PFN_DOWN(CONFIG_DTCM_RAM_BASE)))
  56                 goto panic;
  57
  58         paddr = CONFIG_DTCM_RAM_BASE;
  59
  60         for (i = 0; i < CONFIG_DTCM_NR_PAGES; i++) {
  61                 vaddr = __fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES - i);
  62
  63                 tcm_pte =
  64                         pte_offset_kernel((pmd_t *) pgd_offset_k(vaddr), vaddr);
  65
  66                 set_pte(tcm_pte, pfn_pte(__phys_to_pfn(paddr), PAGE_KERNEL));
  67
  68                 flush_tlb_one(vaddr);
  69
  70                 paddr = paddr + PAGE_SIZE;
  71         }
  72 #endif
  73
  74 #ifndef CONFIG_HAVE_DTCM
  75         memcpy((void *)__fix_to_virt(FIX_TCM),
  76                                 &__tcm_start, &__tcm_end - &__tcm_start);
  77
  78         pr_info("%s: mapping tcm va:0x%08lx to pa:0x%08x\n",
  79                         __func__, __fix_to_virt(FIX_TCM), CONFIG_ITCM_RAM_BASE);
  80
  81         pr_info("%s: __tcm_start va:0x%08lx size:%d\n",
  82                         __func__, (unsigned long)&__tcm_start, &__tcm_end - &__tcm_start);
  83 #else
  84         memcpy((void *)__fix_to_virt(FIX_TCM),
  85                                 &__tcm_start, &__dtcm_start - &__tcm_start);
  86
  87         pr_info("%s: mapping itcm va:0x%08lx to pa:0x%08x\n",
  88                         __func__, __fix_to_virt(FIX_TCM), CONFIG_ITCM_RAM_BASE);
  89
  90         pr_info("%s: __itcm_start va:0x%08lx size:%d\n",
  91                         __func__, (unsigned long)&__tcm_start, &__dtcm_start - &__tcm_start);
  92
  93         memcpy((void *)__fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES),
  94                                 &__dtcm_start, &__tcm_end - &__dtcm_start);
  95
  96         pr_info("%s: mapping dtcm va:0x%08lx to pa:0x%08x\n",
  97                         __func__, __fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES),
  98                                                 CONFIG_DTCM_RAM_BASE);
  99
 100         pr_info("%s: __dtcm_start va:0x%08lx size:%d\n",
 101                         __func__, (unsigned long)&__dtcm_start, &__tcm_end - &__dtcm_start);
 102
 103 #endif
 104         return;
 105 panic:
 106         panic("TCM init error");
 107 }
 108
 109 void *tcm_alloc(size_t len)
 110 {
 111         unsigned long vaddr;
 112
 113         if (!tcm_pool)
 114                 return NULL;
 115
 116         vaddr = gen_pool_alloc(tcm_pool, len);
 117         if (!vaddr)
 118                 return NULL;
 119
 120         return (void *) vaddr;
 121 }
 122 EXPORT_SYMBOL(tcm_alloc);
 123
 124 void tcm_free(void *addr, size_t len)
 125 {
 126         gen_pool_free(tcm_pool, (unsigned long) addr, len);
 127 }
 128 EXPORT_SYMBOL(tcm_free);
 129
 130 static int __init tcm_setup_pool(void)
 131 {
 132 #ifndef CONFIG_HAVE_DTCM
 133         u32 pool_size = (u32) (TCM_NR_PAGES * PAGE_SIZE)
 134                                 - (u32) (&__tcm_end - &__tcm_start);
 135
 136         u32 tcm_pool_start = __fix_to_virt(FIX_TCM)
 137                                 + (u32) (&__tcm_end - &__tcm_start);
 138 #else
 139         u32 pool_size = (u32) (CONFIG_DTCM_NR_PAGES * PAGE_SIZE)
 140                                 - (u32) (&__tcm_end - &__dtcm_start);
 141
 142         u32 tcm_pool_start = __fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES)
 143                                 + (u32) (&__tcm_end - &__dtcm_start);
 144 #endif
 145         int ret;
 146
 147         tcm_pool = gen_pool_create(2, -1);
 148
 149         ret = gen_pool_add(tcm_pool, tcm_pool_start, pool_size, -1);
 150         if (ret) {
 151                 pr_err("%s: gen_pool add failed!\n", __func__);
 152                 return ret;
 153         }
 154
 155         pr_info("%s: Added %d bytes @ 0x%08x to memory pool\n",
 156                 __func__, pool_size, tcm_pool_start);
 157
 158         return 0;
 159 }
 160
 161 static int __init tcm_init(void)
 162 {
 163         tcm_mapping_init();
 164
 165         tcm_setup_pool();
 166
 167         return 0;
 168 }
 169 arch_initcall(tcm_init);