1 // SPDX-License-Identifier: GPL-2.0+
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
8 #include <asm/system.h>
10 #include <linux/compiler.h>
12 #if !(defined(CONFIG_SYS_ICACHE_OFF) && defined(CONFIG_SYS_DCACHE_OFF))
14 DECLARE_GLOBAL_DATA_PTR;
16 __weak void arm_init_before_mmu(void)
20 __weak void arm_init_domains(void)
24 void set_section_dcache(int section, enum dcache_option option)
26 #ifdef CONFIG_ARMV7_LPAE
27 u64 *page_table = (u64 *)gd->arch.tlb_addr;
28 /* Need to set the access flag to not fault */
29 u64 value = TTB_SECT_AP | TTB_SECT_AF;
31 u32 *page_table = (u32 *)gd->arch.tlb_addr;
32 u32 value = TTB_SECT_AP;
35 /* Add the page offset */
36 value |= ((u32)section << MMU_SECTION_SHIFT);
38 /* Add caching bits */
42 page_table[section] = value;
45 __weak void mmu_page_table_flush(unsigned long start, unsigned long stop)
47 debug("%s: Warning: not implemented\n", __func__);
50 void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
51 enum dcache_option option)
53 #ifdef CONFIG_ARMV7_LPAE
54 u64 *page_table = (u64 *)gd->arch.tlb_addr;
56 u32 *page_table = (u32 *)gd->arch.tlb_addr;
58 unsigned long startpt, stoppt;
59 unsigned long upto, end;
61 end = ALIGN(start + size, MMU_SECTION_SIZE) >> MMU_SECTION_SHIFT;
62 start = start >> MMU_SECTION_SHIFT;
63 #ifdef CONFIG_ARMV7_LPAE
64 debug("%s: start=%pa, size=%zu, option=%llx\n", __func__, &start, size,
67 debug("%s: start=%pa, size=%zu, option=0x%x\n", __func__, &start, size,
70 for (upto = start; upto < end; upto++)
71 set_section_dcache(upto, option);
74 * Make sure range is cache line aligned
75 * Only CPU maintains page tables, hence it is safe to always
76 * flush complete cache lines...
79 startpt = (unsigned long)&page_table[start];
80 startpt &= ~(CONFIG_SYS_CACHELINE_SIZE - 1);
81 stoppt = (unsigned long)&page_table[end];
82 stoppt = ALIGN(stoppt, CONFIG_SYS_CACHELINE_SIZE);
83 mmu_page_table_flush(startpt, stoppt);
86 __weak void dram_bank_mmu_setup(int bank)
91 debug("%s: bank: %d\n", __func__, bank);
92 for (i = bd->bi_dram[bank].start >> MMU_SECTION_SHIFT;
93 i < (bd->bi_dram[bank].start >> MMU_SECTION_SHIFT) +
94 (bd->bi_dram[bank].size >> MMU_SECTION_SHIFT);
96 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
97 set_section_dcache(i, DCACHE_WRITETHROUGH);
98 #elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
99 set_section_dcache(i, DCACHE_WRITEALLOC);
101 set_section_dcache(i, DCACHE_WRITEBACK);
106 /* to activate the MMU we need to set up virtual memory: use 1M areas */
107 static inline void mmu_setup(void)
112 arm_init_before_mmu();
113 /* Set up an identity-mapping for all 4GB, rw for everyone */
114 for (i = 0; i < ((4096ULL * 1024 * 1024) >> MMU_SECTION_SHIFT); i++)
115 set_section_dcache(i, DCACHE_OFF);
117 for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
118 dram_bank_mmu_setup(i);
121 #if defined(CONFIG_ARMV7_LPAE) && __LINUX_ARM_ARCH__ != 4
122 /* Set up 4 PTE entries pointing to our 4 1GB page tables */
123 for (i = 0; i < 4; i++) {
124 u64 *page_table = (u64 *)(gd->arch.tlb_addr + (4096 * 4));
125 u64 tpt = gd->arch.tlb_addr + (4096 * i);
126 page_table[i] = tpt | TTB_PAGETABLE;
130 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
131 reg |= TTBCR_ORGN0_WT | TTBCR_IRGN0_WT;
132 #elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
133 reg |= TTBCR_ORGN0_WBWA | TTBCR_IRGN0_WBWA;
135 reg |= TTBCR_ORGN0_WBNWA | TTBCR_IRGN0_WBNWA;
139 /* Set HTCR to enable LPAE */
140 asm volatile("mcr p15, 4, %0, c2, c0, 2"
141 : : "r" (reg) : "memory");
143 asm volatile("mcrr p15, 4, %0, %1, c2"
145 : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
148 asm volatile("mcr p15, 4, %0, c10, c2, 0"
149 : : "r" (MEMORY_ATTRIBUTES) : "memory");
151 /* Set TTBCR to enable LPAE */
152 asm volatile("mcr p15, 0, %0, c2, c0, 2"
153 : : "r" (reg) : "memory");
154 /* Set 64-bit TTBR0 */
155 asm volatile("mcrr p15, 0, %0, %1, c2"
157 : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
160 asm volatile("mcr p15, 0, %0, c10, c2, 0"
161 : : "r" (MEMORY_ATTRIBUTES) : "memory");
163 #elif defined(CONFIG_CPU_V7)
165 /* Set HTCR to disable LPAE */
166 asm volatile("mcr p15, 4, %0, c2, c0, 2"
167 : : "r" (0) : "memory");
169 /* Set TTBCR to disable LPAE */
170 asm volatile("mcr p15, 0, %0, c2, c0, 2"
171 : : "r" (0) : "memory");
174 reg = gd->arch.tlb_addr & TTBR0_BASE_ADDR_MASK;
175 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
176 reg |= TTBR0_RGN_WT | TTBR0_IRGN_WT;
177 #elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
178 reg |= TTBR0_RGN_WBWA | TTBR0_IRGN_WBWA;
180 reg |= TTBR0_RGN_WB | TTBR0_IRGN_WB;
182 asm volatile("mcr p15, 0, %0, c2, c0, 0"
183 : : "r" (reg) : "memory");
185 /* Copy the page table address to cp15 */
186 asm volatile("mcr p15, 0, %0, c2, c0, 0"
187 : : "r" (gd->arch.tlb_addr) : "memory");
189 /* Set the access control to all-supervisor */
190 asm volatile("mcr p15, 0, %0, c3, c0, 0"
195 /* and enable the mmu */
196 reg = get_cr(); /* get control reg. */
200 static int mmu_enabled(void)
202 return get_cr() & CR_M;
205 /* cache_bit must be either CR_I or CR_C */
206 static void cache_enable(uint32_t cache_bit)
210 /* The data cache is not active unless the mmu is enabled too */
211 if ((cache_bit == CR_C) && !mmu_enabled())
213 reg = get_cr(); /* get control reg. */
214 set_cr(reg | cache_bit);
217 /* cache_bit must be either CR_I or CR_C */
218 static void cache_disable(uint32_t cache_bit)
224 if (cache_bit == CR_C) {
225 /* if cache isn;t enabled no need to disable */
226 if ((reg & CR_C) != CR_C)
228 /* if disabling data cache, disable mmu too */
233 if (cache_bit == (CR_C | CR_M))
235 set_cr(reg & ~cache_bit);
239 #ifdef CONFIG_SYS_ICACHE_OFF
240 void icache_enable (void)
245 void icache_disable (void)
250 int icache_status (void)
252 return 0; /* always off */
255 void icache_enable(void)
260 void icache_disable(void)
265 int icache_status(void)
267 return (get_cr() & CR_I) != 0;
271 #ifdef CONFIG_SYS_DCACHE_OFF
272 void dcache_enable (void)
277 void dcache_disable (void)
282 int dcache_status (void)
284 return 0; /* always off */
287 void dcache_enable(void)
292 void dcache_disable(void)
297 int dcache_status(void)
299 return (get_cr() & CR_C) != 0;