csky/mm/tcm.c

0001 // SPDX-License-Identifier: GPL-2.0
0002
0003 #include <linux/highmem.h>
0004 #include <linux/genalloc.h>
0005 #include <asm/tlbflush.h>
0006 #include <asm/fixmap.h>
0007
0008 #if (CONFIG_ITCM_RAM_BASE == 0xffffffff)
0009 #error "You should define ITCM_RAM_BASE"
0010 #endif
0011
0012 #ifdef CONFIG_HAVE_DTCM
0013 #if (CONFIG_DTCM_RAM_BASE == 0xffffffff)
0014 #error "You should define DTCM_RAM_BASE"
0015 #endif
0016
0017 #if (CONFIG_DTCM_RAM_BASE == CONFIG_ITCM_RAM_BASE)
0018 #error "You should define correct DTCM_RAM_BASE"
0019 #endif
0020 #endif
0021
0022 extern char __tcm_start, __tcm_end, __dtcm_start;
0023
0024 static struct gen_pool *tcm_pool;
0025
0026 static void __init tcm_mapping_init(void)
0027 {
0028     pte_t *tcm_pte;
0029     unsigned long vaddr, paddr;
0030     int i;
0031
0032     paddr = CONFIG_ITCM_RAM_BASE;
0033
0034     if (pfn_valid(PFN_DOWN(CONFIG_ITCM_RAM_BASE)))
0035         goto panic;
0036
0037 #ifndef CONFIG_HAVE_DTCM
0038     for (i = 0; i < TCM_NR_PAGES; i++) {
0039 #else
0040     for (i = 0; i < CONFIG_ITCM_NR_PAGES; i++) {
0041 #endif
0042         vaddr = __fix_to_virt(FIX_TCM - i);
0043
0044         tcm_pte =
0045             pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
0046
0047         set_pte(tcm_pte, pfn_pte(__phys_to_pfn(paddr), PAGE_KERNEL));
0048
0049         flush_tlb_one(vaddr);
0050
0051         paddr = paddr + PAGE_SIZE;
0052     }
0053
0054 #ifdef CONFIG_HAVE_DTCM
0055     if (pfn_valid(PFN_DOWN(CONFIG_DTCM_RAM_BASE)))
0056         goto panic;
0057
0058     paddr = CONFIG_DTCM_RAM_BASE;
0059
0060     for (i = 0; i < CONFIG_DTCM_NR_PAGES; i++) {
0061         vaddr = __fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES - i);
0062
0063         tcm_pte =
0064             pte_offset_kernel((pmd_t *) pgd_offset_k(vaddr), vaddr);
0065
0066         set_pte(tcm_pte, pfn_pte(__phys_to_pfn(paddr), PAGE_KERNEL));
0067
0068         flush_tlb_one(vaddr);
0069
0070         paddr = paddr + PAGE_SIZE;
0071     }
0072 #endif
0073
0074 #ifndef CONFIG_HAVE_DTCM
0075     memcpy((void *)__fix_to_virt(FIX_TCM),
0076                 &__tcm_start, &__tcm_end - &__tcm_start);
0077
0078     pr_info("%s: mapping tcm va:0x%08lx to pa:0x%08x\n",
0079             __func__, __fix_to_virt(FIX_TCM), CONFIG_ITCM_RAM_BASE);
0080
0081     pr_info("%s: __tcm_start va:0x%08lx size:%d\n",
0082             __func__, (unsigned long)&__tcm_start, &__tcm_end - &__tcm_start);
0083 #else
0084     memcpy((void *)__fix_to_virt(FIX_TCM),
0085                 &__tcm_start, &__dtcm_start - &__tcm_start);
0086
0087     pr_info("%s: mapping itcm va:0x%08lx to pa:0x%08x\n",
0088             __func__, __fix_to_virt(FIX_TCM), CONFIG_ITCM_RAM_BASE);
0089
0090     pr_info("%s: __itcm_start va:0x%08lx size:%d\n",
0091             __func__, (unsigned long)&__tcm_start, &__dtcm_start - &__tcm_start);
0092
0093     memcpy((void *)__fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES),
0094                 &__dtcm_start, &__tcm_end - &__dtcm_start);
0095
0096     pr_info("%s: mapping dtcm va:0x%08lx to pa:0x%08x\n",
0097             __func__, __fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES),
0098                         CONFIG_DTCM_RAM_BASE);
0099
0100     pr_info("%s: __dtcm_start va:0x%08lx size:%d\n",
0101             __func__, (unsigned long)&__dtcm_start, &__tcm_end - &__dtcm_start);
0102
0103 #endif
0104     return;
0105 panic:
0106     panic("TCM init error");
0107 }
0108
0109 void *tcm_alloc(size_t len)
0110 {
0111     unsigned long vaddr;
0112
0113     if (!tcm_pool)
0114         return NULL;
0115
0116     vaddr = gen_pool_alloc(tcm_pool, len);
0117     if (!vaddr)
0118         return NULL;
0119
0120     return (void *) vaddr;
0121 }
0122 EXPORT_SYMBOL(tcm_alloc);
0123
0124 void tcm_free(void *addr, size_t len)
0125 {
0126     gen_pool_free(tcm_pool, (unsigned long) addr, len);
0127 }
0128 EXPORT_SYMBOL(tcm_free);
0129
0130 static int __init tcm_setup_pool(void)
0131 {
0132 #ifndef CONFIG_HAVE_DTCM
0133     u32 pool_size = (u32) (TCM_NR_PAGES * PAGE_SIZE)
0134                 - (u32) (&__tcm_end - &__tcm_start);
0135
0136     u32 tcm_pool_start = __fix_to_virt(FIX_TCM)
0137                 + (u32) (&__tcm_end - &__tcm_start);
0138 #else
0139     u32 pool_size = (u32) (CONFIG_DTCM_NR_PAGES * PAGE_SIZE)
0140                 - (u32) (&__tcm_end - &__dtcm_start);
0141
0142     u32 tcm_pool_start = __fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES)
0143                 + (u32) (&__tcm_end - &__dtcm_start);
0144 #endif
0145     int ret;
0146
0147     tcm_pool = gen_pool_create(2, -1);
0148
0149     ret = gen_pool_add(tcm_pool, tcm_pool_start, pool_size, -1);
0150     if (ret) {
0151         pr_err("%s: gen_pool add failed!\n", __func__);
0152         return ret;
0153     }
0154
0155     pr_info("%s: Added %d bytes @ 0x%08x to memory pool\n",
0156         __func__, pool_size, tcm_pool_start);
0157
0158     return 0;
0159 }
0160
0161 static int __init tcm_init(void)
0162 {
0163     tcm_mapping_init();
0164
0165     tcm_setup_pool();
0166
0167     return 0;
0168 }
0169 arch_initcall(tcm_init);