[U-Boot] [PATCH v4 1/2] armv7m: add instruction & data cache support
Vikas Manocha
vikas.manocha at st.com
Mon Mar 27 20:02:44 UTC 2017
This patch adds armv7m instruction & data cache support.
Signed-off-by: Vikas Manocha <vikas.manocha at st.com>
cc: Christophe KERELLO <christophe.kerello at st.com>
---
Changed in v4:
- invalidate_dcache_range() & flush_dcache_range() function added.
- blank lines added.
- comments added for registers, functions & barriers.
- register names changed for better clarity.
- typecasting moved to macro definitions.
Changed in v3:
- uint32 replcaed with u32.
- multiple read of hardware register replaced with single.
- pointers replaced with macros for base address.
- register names added as comment for system control block registers.
Changed in v2:
- changed strucures for memory mapped cache registers to macros
- added lines better readability.
- replaced magic numbers with macros.
arch/arm/cpu/armv7m/Makefile | 3 +-
arch/arm/cpu/armv7m/cache.c | 336 ++++++++++++++++++++++++++++++++++++++++++
arch/arm/include/asm/armv7m.h | 26 +++-
arch/arm/lib/Makefile | 2 +
4 files changed, 363 insertions(+), 4 deletions(-)
create mode 100644 arch/arm/cpu/armv7m/cache.c
diff --git a/arch/arm/cpu/armv7m/Makefile b/arch/arm/cpu/armv7m/Makefile
index e1a6c40..93c9085 100644
--- a/arch/arm/cpu/armv7m/Makefile
+++ b/arch/arm/cpu/armv7m/Makefile
@@ -6,6 +6,5 @@
#
extra-y := start.o
-obj-y += cpu.o
-
+obj-y += cpu.o cache.o
obj-$(CONFIG_SYS_ARCH_TIMER) += systick-timer.o
diff --git a/arch/arm/cpu/armv7m/cache.c b/arch/arm/cpu/armv7m/cache.c
new file mode 100644
index 0000000..162cfe3
--- /dev/null
+++ b/arch/arm/cpu/armv7m/cache.c
@@ -0,0 +1,336 @@
+/*
+ * (C) Copyright 2017
+ * Vikas Manocha, ST Micoelectronics, vikas.manocha at st.com.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <asm/armv7m.h>
+#include <asm/io.h>
+
+/* Cache maintenance operation registers */
+
+#define V7M_CACHE_REG_ICIALLU ((u32 *)(V7M_CACHE_MAINT_BASE + 0x00))
+#define INVAL_ICACHE_POU 0
+#define V7M_CACHE_REG_ICIMVALU ((u32 *)(V7M_CACHE_MAINT_BASE + 0x08))
+#define V7M_CACHE_REG_DCIMVAC ((u32 *)(V7M_CACHE_MAINT_BASE + 0x0C))
+#define V7M_CACHE_REG_DCISW ((u32 *)(V7M_CACHE_MAINT_BASE + 0x10))
+#define V7M_CACHE_REG_DCCMVAU ((u32 *)(V7M_CACHE_MAINT_BASE + 0x14))
+#define V7M_CACHE_REG_DCCMVAC ((u32 *)(V7M_CACHE_MAINT_BASE + 0x18))
+#define V7M_CACHE_REG_DCCSW ((u32 *)(V7M_CACHE_MAINT_BASE + 0x1C))
+#define V7M_CACHE_REG_DCCIMVAC ((u32 *)(V7M_CACHE_MAINT_BASE + 0x20))
+#define V7M_CACHE_REG_DCCISW ((u32 *)(V7M_CACHE_MAINT_BASE + 0x24))
+#define WAYS_SHIFT 30
+#define SETS_SHIFT 5
+
+/* armv7m processor feature registers */
+
+#define V7M_PROC_REG_CLIDR ((u32 *)(V7M_PROC_FTR_BASE + 0x00))
+#define V7M_PROC_REG_CTR ((u32 *)(V7M_PROC_FTR_BASE + 0x04))
+#define V7M_PROC_REG_CCSIDR ((u32 *)(V7M_PROC_FTR_BASE + 0x08))
+#define MASK_NUM_WAYS GENMASK(12, 3)
+#define MASK_NUM_SETS GENMASK(27, 13)
+#define CLINE_SIZE_MASK GENMASK(2, 0)
+#define NUM_WAYS_SHIFT 3
+#define NUM_SETS_SHIFT 13
+#define V7M_PROC_REG_CSSELR ((u32 *)(V7M_PROC_FTR_BASE + 0x0C))
+#define SEL_I_OR_D BIT(0)
+
+enum cache_type {
+ DCACHE,
+ ICACHE,
+};
+
+/* PoU : Point of Unification, Poc: Point of Coherency */
+enum cache_action {
+ INVALIDATE_POU, /* i-cache invalidate by address */
+ INVALIDATE_POC, /* d-cache invalidate by address */
+ INVALIDATE_SET_WAY, /* d-cache invalidate by sets/ways */
+ FLUSH_POU, /* d-cache clean by address to the PoU */
+ FLUSH_POC, /* d-cache clean by address to the PoC */
+ FLUSH_SET_WAY, /* d-cache clean by sets/ways */
+ FLUSH_INVAL_POC, /* d-cache clean & invalidate by addr to PoC */
+ FLUSH_INVAL_SET_WAY, /* d-cache clean & invalidate by set/ways */
+};
+
+#ifndef CONFIG_SYS_DCACHE_OFF
+struct dcache_config {
+ u32 ways;
+ u32 sets;
+};
+
+static void get_cache_ways_sets(struct dcache_config *cache)
+{
+ u32 cache_size_id = readl(V7M_PROC_REG_CCSIDR);
+
+ cache->ways = (cache_size_id & MASK_NUM_WAYS) >> NUM_WAYS_SHIFT;
+ cache->sets = (cache_size_id & MASK_NUM_SETS) >> NUM_SETS_SHIFT;
+}
+
+/*
+ * Return the io register to perform required cache action like clean or clean
+ * & invalidate by sets/ways.
+ */
+static u32 *get_action_reg_set_ways(enum cache_action action)
+{
+ switch (action) {
+ case INVALIDATE_SET_WAY:
+ return V7M_CACHE_REG_DCISW;
+ case FLUSH_SET_WAY:
+ return V7M_CACHE_REG_DCCSW;
+ case FLUSH_INVAL_SET_WAY:
+ return V7M_CACHE_REG_DCCISW;
+ default:
+ break;
+ };
+
+ return NULL;
+}
+
+/*
+ * Return the io register to perform required cache action like clean or clean
+ * & invalidate by adddress or range.
+ */
+static u32 *get_action_reg_range(enum cache_action action)
+{
+ switch (action) {
+ case INVALIDATE_POU:
+ return V7M_CACHE_REG_ICIMVALU;
+ case INVALIDATE_POC:
+ return V7M_CACHE_REG_DCIMVAC;
+ case FLUSH_POU:
+ return V7M_CACHE_REG_DCCMVAU;
+ case FLUSH_POC:
+ return V7M_CACHE_REG_DCCMVAC;
+ case FLUSH_INVAL_POC:
+ return V7M_CACHE_REG_DCCIMVAC;
+ default:
+ break;
+ }
+
+ return NULL;
+}
+
+static u32 get_cline_size(enum cache_type type)
+{
+ u32 size;
+
+ if (type == DCACHE)
+ clrbits_le32(V7M_PROC_REG_CSSELR, BIT(SEL_I_OR_D));
+ else if (type == ICACHE)
+ setbits_le32(V7M_PROC_REG_CSSELR, BIT(SEL_I_OR_D));
+ /* Make sure cache selection is effective for next memory access */
+ dsb();
+
+ size = readl(V7M_PROC_REG_CCSIDR) & CLINE_SIZE_MASK;
+ /* Size enocoded as 2 less than log(no_of_words_in_cache_line) base 2 */
+ size = 1 << (size + 2);
+ debug("cache line size is %d\n", size);
+
+ return size;
+}
+
+/* Perform the action like invalidate/clean on a range of cache addresses */
+static int action_cache_range(enum cache_action action, u32 start_addr,
+ int64_t size)
+{
+ u32 cline_size;
+ u32 *action_reg;
+ enum cache_type type;
+
+ action_reg = get_action_reg_range(action);
+ if (!action_reg)
+ return -EINVAL;
+ if (action == INVALIDATE_POU)
+ type = ICACHE;
+ else
+ type = DCACHE;
+
+ /* Cache line size is minium size for the cache action */
+ cline_size = get_cline_size(type);
+ /* Align start address to cache line boundary */
+ start_addr &= ~(cline_size - 1);
+ debug("total size for cache action = %llx\n", size);
+ do {
+ writel(start_addr, action_reg);
+ size -= cline_size;
+ start_addr += cline_size;
+ } while (size > cline_size);
+
+ /* Make sure cache action is effective for next memory access */
+ dsb();
+ isb(); /* Make sure instruction stream sees it */
+ debug("cache action on range done\n");
+
+ return 0;
+}
+
+/* Perform the action like invalidate/clean on all cached addresses */
+static int action_dcache_all(enum cache_action action)
+{
+ struct dcache_config cache;
+ u32 *action_reg;
+ int i, j;
+
+ action_reg = get_action_reg_set_ways(action);
+ if (!action_reg)
+ return -EINVAL;
+
+ clrbits_le32(V7M_PROC_REG_CSSELR, BIT(SEL_I_OR_D));
+ /* Make sure cache selection is effective for next memory access */
+ dsb();
+
+ get_cache_ways_sets(&cache); /* Get number of ways & sets */
+ debug("cache: ways= %d, sets= %d\n", cache.ways + 1, cache.sets + 1);
+ for (i = cache.sets; i >= 0; i--) {
+ for (j = cache.ways; j >= 0; j--) {
+ writel((j << WAYS_SHIFT) | (i << SETS_SHIFT),
+ action_reg);
+ }
+ }
+
+ /* Make sure cache action is effective for next memory access */
+ dsb();
+ isb(); /* Make sure instruction stream sees it */
+
+ return 0;
+}
+
+void dcache_enable(void)
+{
+ if (dcache_status()) /* return if cache already enabled */
+ return;
+
+ if (action_dcache_all(INVALIDATE_SET_WAY)) {
+ printf("ERR: D-cache not enabled\n");
+ return;
+ }
+
+ setbits_le32(&V7M_SCB->ccr, BIT(V7M_CCR_DCACHE));
+
+ /* Make sure cache action is effective for next memory access */
+ dsb();
+ isb(); /* Make sure instruction stream sees it */
+}
+
+void dcache_disable(void)
+{
+ if (!dcache_status())
+ return;
+
+ /* if dcache is enabled-> dcache disable & then flush */
+ if (action_dcache_all(FLUSH_SET_WAY)) {
+ printf("ERR: D-cache not flushed\n");
+ return;
+ }
+
+ clrbits_le32(&V7M_SCB->ccr, BIT(V7M_CCR_DCACHE));
+
+ /* Make sure cache action is effective for next memory access */
+ dsb();
+ isb(); /* Make sure instruction stream sees it */
+}
+
+int dcache_status(void)
+{
+ return (readl(&V7M_SCB->ccr) & BIT(V7M_CCR_DCACHE)) != 0;
+}
+
+void invalidate_dcache_range(unsigned long start, unsigned long stop)
+{
+ if (action_cache_range(INVALIDATE_POC, start, stop - start)) {
+ printf("ERR: D-cache not invalidated\n");
+ return;
+ }
+}
+
+void flush_dcache_range(unsigned long start, unsigned long stop)
+{
+ if (action_cache_range(FLUSH_POC, start, stop - start)) {
+ printf("ERR: D-cache not flushed\n");
+ return;
+ }
+}
+#else
+void dcache_enable(void)
+{
+ return;
+}
+
+void dcache_disable(void)
+{
+ return;
+}
+
+int dcache_status(void)
+{
+ return 0;
+}
+#endif
+
+#ifndef CONFIG_SYS_ICACHE_OFF
+
+void invalidate_icache_all(void)
+{
+ writel(INVAL_ICACHE_POU, V7M_CACHE_REG_ICIALLU);
+
+ /* Make sure cache action is effective for next memory access */
+ dsb();
+ isb(); /* Make sure instruction stream sees it */
+}
+
+void icache_enable(void)
+{
+ if (icache_status())
+ return;
+
+ invalidate_icache_all();
+ setbits_le32(&V7M_SCB->ccr, BIT(V7M_CCR_ICACHE));
+
+ /* Make sure cache action is effective for next memory access */
+ dsb();
+ isb(); /* Make sure instruction stream sees it */
+}
+
+int icache_status(void)
+{
+ return (readl(&V7M_SCB->ccr) & BIT(V7M_CCR_ICACHE)) != 0;
+}
+
+void icache_disable(void)
+{
+ if (!icache_status())
+ return;
+
+ isb(); /* flush pipeline */
+ clrbits_le32(&V7M_SCB->ccr, BIT(V7M_CCR_ICACHE));
+ isb(); /* subsequent instructions fetch see cache disable effect */
+}
+#else
+void icache_enable(void)
+{
+ return;
+}
+
+void icache_disable(void)
+{
+ return;
+}
+
+int icache_status(void)
+{
+ return 0;
+}
+#endif
+
+void enable_caches(void)
+{
+#ifndef CONFIG_SYS_ICACHE_OFF
+ icache_enable();
+#endif
+#ifndef CONFIG_SYS_DCACHE_OFF
+ dcache_enable();
+#endif
+}
diff --git a/arch/arm/include/asm/armv7m.h b/arch/arm/include/asm/armv7m.h
index 54d8a2b..ebf0f17 100644
--- a/arch/arm/include/asm/armv7m.h
+++ b/arch/arm/include/asm/armv7m.h
@@ -16,8 +16,15 @@
.thumb
#endif
-#define V7M_SCB_BASE 0xE000ED00
-#define V7M_MPU_BASE 0xE000ED90
+/* armv7m fixed base addresses */
+#define V7M_SCS_BASE 0xE000E000
+#define V7M_NVIC_BASE (V7M_SCS_BASE + 0x0100)
+#define V7M_SCB_BASE (V7M_SCS_BASE + 0x0D00)
+#define V7M_PROC_FTR_BASE (V7M_SCS_BASE + 0x0D78)
+#define V7M_MPU_BASE (V7M_SCS_BASE + 0x0D90)
+#define V7M_FPU_BASE (V7M_SCS_BASE + 0x0F30)
+#define V7M_CACHE_MAINT_BASE (V7M_SCS_BASE + 0x0F50)
+#define V7M_ACCESS_CNTL_BASE (V7M_SCS_BASE + 0x0F90)
#define V7M_SCB_VTOR 0x08
@@ -27,6 +34,18 @@ struct v7m_scb {
uint32_t icsr; /* Interrupt Control and State Register */
uint32_t vtor; /* Vector Table Offset Register */
uint32_t aircr; /* App Interrupt and Reset Control Register */
+ uint32_t scr; /* offset 0x10: System Control Register */
+ uint32_t ccr; /* offset 0x14: Config and Control Register */
+ uint32_t shpr1; /* offset 0x18: System Handler Priority Reg 1 */
+ uint32_t shpr2; /* offset 0x1c: System Handler Priority Reg 2 */
+ uint32_t shpr3; /* offset 0x20: System Handler Priority Reg 3 */
+ uint32_t shcrs; /* offset 0x24: System Handler Control State */
+ uint32_t cfsr; /* offset 0x28: Configurable Fault Status Reg */
+ uint32_t hfsr; /* offset 0x2C: HardFault Status Register */
+ uint32_t res; /* offset 0x30: reserved */
+ uint32_t mmar; /* offset 0x34: MemManage Fault Address Reg */
+ uint32_t bfar; /* offset 0x38: BusFault Address Reg */
+ uint32_t afsr; /* offset 0x3C: Auxiliary Fault Status Reg */
};
#define V7M_SCB ((struct v7m_scb *)V7M_SCB_BASE)
@@ -39,6 +58,9 @@ struct v7m_scb {
#define V7M_ICSR_VECTACT_MSK 0xFF
+#define V7M_CCR_DCACHE 16
+#define V7M_CCR_ICACHE 17
+
struct v7m_mpu {
uint32_t type; /* Type Register */
uint32_t ctrl; /* Control Register */
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 166fa9e..52b36b3 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -55,8 +55,10 @@ endif
obj-y += cache.o
ifndef CONFIG_ARM64
+ifndef CONFIG_CPU_V7M
obj-y += cache-cp15.o
endif
+endif
obj-y += psci-dt.o
--
1.9.1
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