[U-Boot] [PATCH v2 03/10] armv7: cache maintenance operations for armv7

Aneesh V
2011-03-08T13:07:31Z

- Add a framework for layered cache maintenance
- separate out SOC specific outer cache maintenance from
maintenance of caches known to CPU

- Add generic ARMv7 cache maintenance operations that affect all
caches known to ARMv7 CPUs. For instance in Cortex-A8 these
opertions will affect both L1 and L2 caches. In Cortex-A9
these will affect only L1 cache

- D-cache operations supported:
- Invalidate entire D-cache
- Invalidate D-cache range
- Flush(clean & invalidate) entire D-cache
- Flush D-cache range
- I-cache operations supported:
- Invalidate entire I-cache

- Add maintenance functions for TLB, branch predictor array etc.

- Enable -march=armv7-a so that armv7 assembly instructions can be
used

Signed-off-by: Aneesh V <aneesh@ti.com>
---
README | 5 +
arch/arm/cpu/armv7/Makefile | 2 +-
arch/arm/cpu/armv7/cache_v7.c | 390 +++++++++++++++++++++++++++++++++++++++++
arch/arm/include/asm/armv7.h | 68 +++++++
include/common.h | 5 +-
5 files changed, 468 insertions(+), 2 deletions(-)
create mode 100644 arch/arm/cpu/armv7/cache_v7.c
create mode 100644 arch/arm/include/asm/armv7.h

diff --git a/README b/README
index 21cd71b..ba01c52 100644
--- a/README
+++ b/README
@@ -448,6 +448,11 @@ The following options need to be configured:
Note: If a "bootargs" environment is defined, it will overwride
the defaults discussed just above.

+- Cache Configuration:
+ CONFIG_SYS_NO_ICACHE - Do not enable instruction cache in U-Boot
+ CONFIG_SYS_NO_DCACHE - Do not enable data cache in U-Boot
+ CONFIG_SYS_NO_L2CACHE- Do not enable L2 cache in U-Boot
+
- Serial Ports:
CONFIG_PL010_SERIAL

diff --git a/arch/arm/cpu/armv7/Makefile b/arch/arm/cpu/armv7/Makefile
index 8c0e915..299792a 100644
--- a/arch/arm/cpu/armv7/Makefile
+++ b/arch/arm/cpu/armv7/Makefile
@@ -26,7 +26,7 @@ include $(TOPDIR)/config.mk
LIB = $(obj)lib$(CPU).o

START := start.o
-COBJS := cpu.o
+COBJS := cpu.o cache_v7.o
COBJS += syslib.o

SRCS := $(START:.o=.S) $(COBJS:.o=.c)
diff --git a/arch/arm/cpu/armv7/cache_v7.c b/arch/arm/cpu/armv7/cache_v7.c
new file mode 100644
index 0000000..46d8e09
--- /dev/null
+++ b/arch/arm/cpu/armv7/cache_v7.c
@@ -0,0 +1,390 @@
+/*
+ * (C) Copyright 2010
+ * Texas Instruments Incorporated - http://www.ti.com/
+ * Aneesh V <aneesh@ti.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#include <linux/types.h>
+#include <common.h>
+#include <asm/armv7.h>
+#include <asm/utils.h>
+
+#define ARMV7_DCACHE_INVAL_ALL 1
+#define ARMV7_DCACHE_CLEAN_INVAL_ALL 2
+#define ARMV7_DCACHE_INVAL_RANGE 3
+#define ARMV7_DCACHE_CLEAN_INVAL_RANGE 4
+
+#ifndef CONFIG_SYS_NO_DCACHE
+/*
+ * Write the level and type you want to Cache Size Selection Register(CSSELR)
+ * to get size details from Current Cache Size ID Register(CCSIDR)
+ */
+static void set_csselr(u32 level, u32 type)
+{ u32 csselr = level << 1 | type;
+
+ /* Write to Cache Size Selection Register(CSSELR) */
+ asm volatile ("mcr p15, 2, %0, c0, c0, 0" : : "r" (csselr));
+}
+
+static u32 get_ccsidr(void)
+{
+ u32 ccsidr;
+
+ /* Read current CP15 Cache Size ID Register */
+ asm volatile ("mrc p15, 1, %0, c0, c0, 0" : "=r" (ccsidr));
+ return ccsidr;
+}
+
+static u32 get_clidr(void)
+{
+ u32 clidr;
+
+ /* Read current CP15 Cache Level ID Register */
+ asm volatile ("mrc p15,1,%0,c0,c0,1" : "=r" (clidr));
+ return clidr;
+}
+
+static void v7_inval_dcache_level_setway(u32 level, u32 num_sets,
+ u32 num_ways, u32 way_shift,
+ u32 log2_line_len)
+{
+ int way, set, setway;
+
+ /*
+ * For optimal assembly code:
+ * a. count down
+ * b. have bigger loop inside
+ */
+ for (way = num_ways - 1; way >= 0 ; way--)
+ for (set = num_sets - 1; set >= 0; set--) {
+ setway = (level << 1) | (set << log2_line_len) |
+ (way << way_shift);
+ /* Invalidate data/unified cache line by set/way */
+ asm volatile (" mcr p15, 0, %0, c7, c6, 2"
+ : : "r" (setway));
+ }
+ /* DMB to make sure the operation is complete */
+ CP15DMB;
+}
+
+static void v7_clean_inval_dcache_level_setway(u32 level, u32 num_sets,
+ u32 num_ways, u32 way_shift,
+ u32 log2_line_len)
+{
+ int way, set, setway;
+
+ /*
+ * For optimal assembly code:
+ * a. count down
+ * b. have bigger loop inside
+ */
+ for (way = num_ways - 1; way >= 0 ; way--)
+ for (set = num_sets - 1; set >= 0; set--) {
+ setway = (level << 1) | (set << log2_line_len) |
+ (way << way_shift);
+ /*
+ * Clean & Invalidate data/unified
+ * cache line by set/way
+ */
+ asm volatile (" mcr p15, 0, %0, c7, c14, 2"
+ : : "r" (setway));
+ }
+ /* DMB to make sure the operation is complete */
+ CP15DMB;
+}
+
+static void v7_maint_dcache_level_setway(u32 level, u32 operation)
+{
+ u32 ccsidr;
+ u32 num_sets, num_ways, log2_line_len, log2_num_ways;
+ u32 way_shift;
+
+ set_csselr(level, ARMV7_CSSELR_IND_DATA_UNIFIED);
+
+ ccsidr = get_ccsidr();
+
+ log2_line_len = get_bit_field(ccsidr, CCSIDR_LINE_SIZE_OFFSET,
+ CCSIDR_LINE_SIZE_MASK) + 2;
+ /* Converting from words to bytes */
+ log2_line_len += 2;
+
+ num_ways = get_bit_field(ccsidr, CCSIDR_ASSOCIATIVITY_OFFSET,
+ CCSIDR_ASSOCIATIVITY_MASK) + 1;
+ num_sets = get_bit_field(ccsidr, CCSIDR_NUM_SETS_OFFSET,
+ CCSIDR_NUM_SETS_MASK) + 1;
+ /*
+ * According to ARMv7 ARM number of sets and number of ways need
+ * not be a power of 2
+ */
+ log2_num_ways = log_2_n_round_up(num_ways);
+
+ way_shift = (32 - log2_num_ways);
+ if (operation == ARMV7_DCACHE_INVAL_ALL)
+ v7_inval_dcache_level_setway(level, num_sets, num_ways,
+ way_shift, log2_line_len);
+ else if (operation == ARMV7_DCACHE_CLEAN_INVAL_ALL)
+ v7_clean_inval_dcache_level_setway(level, num_sets, num_ways,
+ way_shift, log2_line_len);
+}
+
+static void v7_maint_dcache_all(u32 operation)
+{
+ u32 level, cache_type, level_start_bit = 0;
+
+ u32 clidr = get_clidr();
+
+ for (level = 0; level < 7; level++) {
+ cache_type = get_bit_field(clidr, level_start_bit,
+ 0x7 << level_start_bit);
+ if ((cache_type == ARMV7_CLIDR_CTYPE_DATA_ONLY) ||
+ (cache_type == ARMV7_CLIDR_CTYPE_INSTRUCTION_DATA) ||
+ (cache_type == ARMV7_CLIDR_CTYPE_UNIFIED))
+ v7_maint_dcache_level_setway(level, operation);
+ level_start_bit += 3;
+ }
+}
+
+static void v7_dcache_clean_inval_range(u32 start,
+ u32 stop, u32 line_len)
+{
+ u32 mva;
+
+ /* Align start to cache line boundary */
+ start &= ~(line_len - 1);
+ for (mva = start; mva < stop; mva = mva + line_len)
+ /* DCCIMVAC - Clean & Invalidate data cache by MVA to PoC */
+ asm volatile ("mcr p15, 0, %0, c7, c14, 1" : : "r" (mva));
+}
+
+static void v7_dcache_inval_range(u32 start, u32 stop, u32 line_len)
+{
+ u32 mva;
+
+ /*
+ * If start address is not aligned to cache-line flush the first
+ * line to prevent affecting somebody else's buffer
+ */
+ if (start & (line_len - 1)) {
+ v7_dcache_clean_inval_range(start, start + 1, line_len);
+ /* move to next cache line */
+ start = (start + line_len - 1) & ~(line_len - 1);
+ }
+
+ /*
+ * If stop address is not aligned to cache-line flush the last
+ * line to prevent affecting somebody else's buffer
+ */
+ if (stop & (line_len - 1)) {
+ v7_dcache_clean_inval_range(stop, stop + 1, line_len);
+ /* align to the beginning of this cache line */
+ stop &= ~(line_len - 1);
+ }
+
+ for (mva = start; mva < stop; mva = mva + line_len)
+ /* DCIMVAC - Invalidate data cache by MVA to PoC */
+ asm volatile ("mcr p15, 0, %0, c7, c6, 1" : : "r" (mva));
+}
+
+static void v7_dcache_maint_range(u32 start, u32 stop, u32 range_op)
+{
+ u32 line_len, ccsidr;
+
+ ccsidr = get_ccsidr();
+ line_len = get_bit_field(ccsidr, CCSIDR_LINE_SIZE_OFFSET,
+ CCSIDR_LINE_SIZE_MASK) + 2;
+ /* Converting from words to bytes */
+ line_len += 2;
+ /* converting from log2(linelen) to linelen */
+ line_len = 1 << line_len;
+
+ switch (range_op) {
+ case ARMV7_DCACHE_CLEAN_INVAL_RANGE:
+ v7_dcache_clean_inval_range(start, stop, line_len);
+ break;
+ case ARMV7_DCACHE_INVAL_RANGE:
+ v7_dcache_inval_range(start, stop, line_len);
+ break;
+ }
+
+ /* DMB to make sure the operation is complete */
+ CP15DMB;
+}
+
+/* Invalidate TLB */
+static void v7_inval_tlb(void)
+{
+ /* Invalidate entire unified TLB */
+ asm volatile ("mcr p15, 0, %0, c8, c7, 0" : : "r" (0));
+ /* Invalidate entire data TLB */
+ asm volatile ("mcr p15, 0, %0, c8, c6, 0" : : "r" (0));
+ /* Invalidate entire instruction TLB */
+ asm volatile ("mcr p15, 0, %0, c8, c5, 0" : : "r" (0));
+ /* Full system DSB - make sure that the invalidation is complete */
+ CP15DSB;
+ /* Full system ISB - make sure the instruction stream sees it */
+ CP15ISB;
+}
+
+void invalidate_dcache_all(void)
+{
+ v7_maint_dcache_all(ARMV7_DCACHE_INVAL_ALL);
+
+ v7_outer_cache_inval_all();
+}
+
+/*
+ * Performs a clean & invalidation of the entire data cache
+ * at all levels
+ */
+void flush_dcache_all(void)
+{
+ v7_maint_dcache_all(ARMV7_DCACHE_CLEAN_INVAL_ALL);
+
+ v7_outer_cache_flush_all();
+}
+
+/*
+ * Invalidates range in all levels of D-cache/unified cache used:
+ * Affects the range [start, stop - 1]
+ */
+void invalidate_dcache_range(unsigned long start, unsigned long stop)
+{
+
+ v7_dcache_maint_range(start, stop, ARMV7_DCACHE_INVAL_RANGE);
+
+ v7_outer_cache_inval_range(start, stop);
+}
+
+/*
+ * Flush range(clean & invalidate) from all levels of D-cache/unified
+ * cache used:
+ * Affects the range [start, stop - 1]
+ */
+void flush_dcache_range(unsigned long start, unsigned long stop)
+{
+ v7_dcache_maint_range(start, stop, ARMV7_DCACHE_CLEAN_INVAL_RANGE);
+
+ v7_outer_cache_flush_range(start, stop);
+}
+
+void arm_init_before_mmu(void)
+{
+ v7_outer_cache_enable();
+ invalidate_dcache_all();
+ v7_inval_tlb();
+}
+
+/*
+ * Flush range from all levels of d-cache/unified-cache used:
+ * Affects the range [start, start + size - 1]
+ */
+void flush_cache(unsigned long start, unsigned long size)
+{
+ flush_dcache_range(start, start + size);
+}
+#else /* #ifndef CONFIG_SYS_NO_DCACHE */
+void invalidate_dcache_all(void)
+{
+}
+
+void flush_dcache_all(void)
+{
+}
+
+void invalidate_dcache_range(unsigned long start, unsigned long stop)
+{
+}
+
+void flush_dcache_range(unsigned long start, unsigned long stop)
+{
+}
+
+void arm_init_before_mmu(void)
+{
+}
+
+void flush_cache(unsigned long start, unsigned long size)
+{
+}
+#endif /* #ifndef CONFIG_SYS_NO_DCACHE */
+
+#ifndef CONFIG_SYS_NO_ICACHE
+/* Invalidate entire I-cache and branch predictor array */
+void invalidate_icache_all(void)
+{
+ /*
+ * Invalidate all instruction caches to PoU.
+ * Also flushes branch target cache.
+ */
+ asm volatile ("mcr p15, 0, %0, c7, c5, 0" : : "r" (0));
+
+ /* Invalidate entire branch predictor array */
+ asm volatile ("mcr p15, 0, %0, c7, c5, 6" : : "r" (0));
+
+ /* Full system DSB - make sure that the invalidation is complete */
+ CP15DSB;
+
+ /* ISB - make sure the instruction stream sees it */
+ CP15ISB;
+}
+#else
+void invalidate_icache_all(void)
+{
+}
+#endif
+
+/*
+ * Stub implementations for outer cache operations
+ */
+void __v7_outer_cache_enable(void)
+{
+}
+void v7_outer_cache_enable(void)
+ __attribute__((weak, alias("__v7_outer_cache_enable")));
+
+void __v7_outer_cache_disable(void)
+{
+}
+void v7_outer_cache_disable(void)
+ __attribute__((weak, alias("__v7_outer_cache_disable")));
+
+void __v7_outer_cache_flush_all(void)
+{
+}
+void v7_outer_cache_flush_all(void)
+ __attribute__((weak, alias("__v7_outer_cache_flush_all")));
+
+void __v7_outer_cache_inval_all(void)
+{
+}
+void v7_outer_cache_inval_all(void)
+ __attribute__((weak, alias("__v7_outer_cache_inval_all")));
+
+void __v7_outer_cache_flush_range(u32 start, u32 end)
+{
+}
+void v7_outer_cache_flush_range(u32 start, u32 end)
+ __attribute__((weak, alias("__v7_outer_cache_flush_range")));
+
+void __v7_outer_cache_inval_range(u32 start, u32 end)
+{
+}
+void v7_outer_cache_inval_range(u32 start, u32 end)
+ __attribute__((weak, alias("__v7_outer_cache_inval_range")));
diff --git a/arch/arm/include/asm/armv7.h b/arch/arm/include/asm/armv7.h
new file mode 100644
index 0000000..50cc167
--- /dev/null
+++ b/arch/arm/include/asm/armv7.h
@@ -0,0 +1,68 @@
+/*
+ * (C) Copyright 2010
+ * Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * Aneesh V <aneesh@ti.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#ifndef ARMV7_H
+#define ARMV7_H
+#include <linux/types.h>
+
+/* CCSIDR */
+#define CCSIDR_LINE_SIZE_OFFSET 0
+#define CCSIDR_LINE_SIZE_MASK 0x7
+#define CCSIDR_ASSOCIATIVITY_OFFSET 3
+#define CCSIDR_ASSOCIATIVITY_MASK (0x3FF << 3)
+#define CCSIDR_NUM_SETS_OFFSET 13
+#define CCSIDR_NUM_SETS_MASK (0x7FFF << 13)
+
+/*
+ * Values for InD field in CSSELR
+ * Selects the type of cache
+ */
+#define ARMV7_CSSELR_IND_DATA_UNIFIED 0
+#define ARMV7_CSSELR_IND_INSTRUCTION 1
+
+/* Values for Ctype fields in CLIDR */
+#define ARMV7_CLIDR_CTYPE_NO_CACHE 0
+#define ARMV7_CLIDR_CTYPE_INSTRUCTION_ONLY 1
+#define ARMV7_CLIDR_CTYPE_DATA_ONLY 2
+#define ARMV7_CLIDR_CTYPE_INSTRUCTION_DATA 3
+#define ARMV7_CLIDR_CTYPE_UNIFIED 4
+
+/*
+ * CP15 Barrier instructions
+ * Please note that we have separate barrier instructions in ARMv7
+ * However, we use the CP15 based instructtions because we use
+ * -march=armv5 in U-Boot
+ */
+#define CP15ISB asm volatile ("mcr p15, 0, %0, c7, c5, 4" : : "r" (0))
+#define CP15DSB asm volatile ("mcr p15, 0, %0, c7, c10, 4" : : "r" (0))
+#define CP15DMB asm volatile ("mcr p15, 0, %0, c7, c10, 5" : : "r" (0))
+
+void v7_outer_cache_enable(void);
+void v7_outer_cache_disable(void);
+void v7_outer_cache_flush_all(void);
+void v7_outer_cache_inval_all(void);
+void v7_outer_cache_flush_range(u32 start, u32 end);
+void v7_outer_cache_inval_range(u32 start, u32 end);
+
+#endif
diff --git a/include/common.h b/include/common.h
index d8c912d..46fa112 100644
--- a/include/common.h
+++ b/include/common.h
@@ -411,6 +411,7 @@ void icache_disable(void);
int dcache_status (void);
void dcache_enable (void);
void dcache_disable(void);
+void mmu_disable(void);
void relocate_code (ulong, gd_t *, ulong) __attribute__ ((noreturn));
ulong get_endaddr (void);
void trap_init (ulong);
@@ -603,9 +604,11 @@ ulong video_setmem (ulong);

/* arch/$(ARCH)/lib/cache.c */
void flush_cache (unsigned long, unsigned long);
+void flush_dcache_all(void);
void flush_dcache_range(unsigned long start, unsigned long stop);
void invalidate_dcache_range(unsigned long start, unsigned long stop);
-
+void invalidate_dcache_all(void);
+void invalidate_icache_all(void);

/* arch/$(ARCH)/lib/ticks.S */
unsigned long long get_ticks(void);
--
1.7.0.4