1 // SPDX-License-Identifier: GPL-2.0+
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
9 #include <asm/system.h>
10 #include <asm/cache.h>
11 #include <linux/compiler.h>
12 #include <asm/armv7_mpu.h>
14 #if !(CONFIG_IS_ENABLED(SYS_ICACHE_OFF) && CONFIG_IS_ENABLED(SYS_DCACHE_OFF))
16 DECLARE_GLOBAL_DATA_PTR;
18 #ifdef CONFIG_SYS_ARM_MMU
19 __weak void arm_init_before_mmu(void)
23 __weak void arm_init_domains(void)
27 void set_section_dcache(int section, enum dcache_option option)
29 #ifdef CONFIG_ARMV7_LPAE
30 u64 *page_table = (u64 *)gd->arch.tlb_addr;
31 /* Need to set the access flag to not fault */
32 u64 value = TTB_SECT_AP | TTB_SECT_AF;
34 u32 *page_table = (u32 *)gd->arch.tlb_addr;
35 u32 value = TTB_SECT_AP;
38 /* Add the page offset */
39 value |= ((u32)section << MMU_SECTION_SHIFT);
41 /* Add caching bits */
45 page_table[section] = value;
48 __weak void mmu_page_table_flush(unsigned long start, unsigned long stop)
50 debug("%s: Warning: not implemented\n", __func__);
53 void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
54 enum dcache_option option)
56 #ifdef CONFIG_ARMV7_LPAE
57 u64 *page_table = (u64 *)gd->arch.tlb_addr;
59 u32 *page_table = (u32 *)gd->arch.tlb_addr;
61 unsigned long startpt, stoppt;
62 unsigned long upto, end;
64 end = ALIGN(start + size, MMU_SECTION_SIZE) >> MMU_SECTION_SHIFT;
65 start = start >> MMU_SECTION_SHIFT;
66 #ifdef CONFIG_ARMV7_LPAE
67 debug("%s: start=%pa, size=%zu, option=%llx\n", __func__, &start, size,
70 debug("%s: start=%pa, size=%zu, option=0x%x\n", __func__, &start, size,
73 for (upto = start; upto < end; upto++)
74 set_section_dcache(upto, option);
77 * Make sure range is cache line aligned
78 * Only CPU maintains page tables, hence it is safe to always
79 * flush complete cache lines...
82 startpt = (unsigned long)&page_table[start];
83 startpt &= ~(CONFIG_SYS_CACHELINE_SIZE - 1);
84 stoppt = (unsigned long)&page_table[end];
85 stoppt = ALIGN(stoppt, CONFIG_SYS_CACHELINE_SIZE);
86 mmu_page_table_flush(startpt, stoppt);
89 __weak void dram_bank_mmu_setup(int bank)
94 debug("%s: bank: %d\n", __func__, bank);
95 for (i = bd->bi_dram[bank].start >> MMU_SECTION_SHIFT;
96 i < (bd->bi_dram[bank].start >> MMU_SECTION_SHIFT) +
97 (bd->bi_dram[bank].size >> MMU_SECTION_SHIFT);
99 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
100 set_section_dcache(i, DCACHE_WRITETHROUGH);
101 #elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
102 set_section_dcache(i, DCACHE_WRITEALLOC);
104 set_section_dcache(i, DCACHE_WRITEBACK);
109 /* to activate the MMU we need to set up virtual memory: use 1M areas */
110 static inline void mmu_setup(void)
115 arm_init_before_mmu();
116 /* Set up an identity-mapping for all 4GB, rw for everyone */
117 for (i = 0; i < ((4096ULL * 1024 * 1024) >> MMU_SECTION_SHIFT); i++)
118 set_section_dcache(i, DCACHE_OFF);
120 for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
121 dram_bank_mmu_setup(i);
124 #if defined(CONFIG_ARMV7_LPAE) && __LINUX_ARM_ARCH__ != 4
125 /* Set up 4 PTE entries pointing to our 4 1GB page tables */
126 for (i = 0; i < 4; i++) {
127 u64 *page_table = (u64 *)(gd->arch.tlb_addr + (4096 * 4));
128 u64 tpt = gd->arch.tlb_addr + (4096 * i);
129 page_table[i] = tpt | TTB_PAGETABLE;
133 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
134 reg |= TTBCR_ORGN0_WT | TTBCR_IRGN0_WT;
135 #elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
136 reg |= TTBCR_ORGN0_WBWA | TTBCR_IRGN0_WBWA;
138 reg |= TTBCR_ORGN0_WBNWA | TTBCR_IRGN0_WBNWA;
142 /* Set HTCR to enable LPAE */
143 asm volatile("mcr p15, 4, %0, c2, c0, 2"
144 : : "r" (reg) : "memory");
146 asm volatile("mcrr p15, 4, %0, %1, c2"
148 : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
151 asm volatile("mcr p15, 4, %0, c10, c2, 0"
152 : : "r" (MEMORY_ATTRIBUTES) : "memory");
154 /* Set TTBCR to enable LPAE */
155 asm volatile("mcr p15, 0, %0, c2, c0, 2"
156 : : "r" (reg) : "memory");
157 /* Set 64-bit TTBR0 */
158 asm volatile("mcrr p15, 0, %0, %1, c2"
160 : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
163 asm volatile("mcr p15, 0, %0, c10, c2, 0"
164 : : "r" (MEMORY_ATTRIBUTES) : "memory");
166 #elif defined(CONFIG_CPU_V7A)
168 /* Set HTCR to disable LPAE */
169 asm volatile("mcr p15, 4, %0, c2, c0, 2"
170 : : "r" (0) : "memory");
172 /* Set TTBCR to disable LPAE */
173 asm volatile("mcr p15, 0, %0, c2, c0, 2"
174 : : "r" (0) : "memory");
177 reg = gd->arch.tlb_addr & TTBR0_BASE_ADDR_MASK;
178 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
179 reg |= TTBR0_RGN_WT | TTBR0_IRGN_WT;
180 #elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
181 reg |= TTBR0_RGN_WBWA | TTBR0_IRGN_WBWA;
183 reg |= TTBR0_RGN_WB | TTBR0_IRGN_WB;
185 asm volatile("mcr p15, 0, %0, c2, c0, 0"
186 : : "r" (reg) : "memory");
188 /* Copy the page table address to cp15 */
189 asm volatile("mcr p15, 0, %0, c2, c0, 0"
190 : : "r" (gd->arch.tlb_addr) : "memory");
192 /* Set the access control to all-supervisor */
193 asm volatile("mcr p15, 0, %0, c3, c0, 0"
198 /* and enable the mmu */
199 reg = get_cr(); /* get control reg. */
203 static int mmu_enabled(void)
205 return get_cr() & CR_M;
207 #endif /* CONFIG_SYS_ARM_MMU */
209 /* cache_bit must be either CR_I or CR_C */
210 static void cache_enable(uint32_t cache_bit)
214 /* The data cache is not active unless the mmu/mpu is enabled too */
215 #ifdef CONFIG_SYS_ARM_MMU
216 if ((cache_bit == CR_C) && !mmu_enabled())
218 #elif defined(CONFIG_SYS_ARM_MPU)
219 if ((cache_bit == CR_C) && !mpu_enabled()) {
220 printf("Consider enabling MPU before enabling caches\n");
224 reg = get_cr(); /* get control reg. */
225 set_cr(reg | cache_bit);
228 /* cache_bit must be either CR_I or CR_C */
229 static void cache_disable(uint32_t cache_bit)
235 if (cache_bit == CR_C) {
236 /* if cache isn;t enabled no need to disable */
237 if ((reg & CR_C) != CR_C)
239 #ifdef CONFIG_SYS_ARM_MMU
240 /* if disabling data cache, disable mmu too */
246 #ifdef CONFIG_SYS_ARM_MMU
247 if (cache_bit == (CR_C | CR_M))
248 #elif defined(CONFIG_SYS_ARM_MPU)
249 if (cache_bit == CR_C)
252 set_cr(reg & ~cache_bit);
256 #if CONFIG_IS_ENABLED(SYS_ICACHE_OFF)
257 void icache_enable(void)
262 void icache_disable(void)
267 int icache_status(void)
269 return 0; /* always off */
272 void icache_enable(void)
277 void icache_disable(void)
282 int icache_status(void)
284 return (get_cr() & CR_I) != 0;
288 #if CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
289 void dcache_enable(void)
294 void dcache_disable(void)
299 int dcache_status(void)
301 return 0; /* always off */
304 void dcache_enable(void)
309 void dcache_disable(void)
314 int dcache_status(void)
316 return (get_cr() & CR_C) != 0;