armv7a: fix handling of inner caches

ARMv7 architecture allows up to 7 cache levels that are architecturally
visible, as opposed to "system caches", which are outside of the domain
defined by ARMv7 and require separate management. This patch enables
detection and identification of caches at all levels. It also implements
a new "flush-all" function that cleans & invalidates all cache levels to
the "Point of Coherence".

Change-Id: Ib77115d6044d39845907941c6f031e208f6e0aa5
Signed-off-by: Matthias Welwarsky <matthias@welwarsky.de>
Reviewed-on: http://openocd.zylin.com/3024
Reviewed-by: Paul Fertser <fercerpav@gmail.com>
Tested-by: jenkins

1 files changed, 138 insertions, 117 deletions

diff --git a/src/target/armv7a.c b/src/target/armv7a.c
index e274785..18416e5 100644
--- a/src/target/armv7a.c
+++ b/src/target/armv7a.c
@@ -379,24 +379,42 @@ done:
 static int armv7a_handle_inner_cache_info_command(struct command_context *cmd_ctx,
 	struct armv7a_cache_common *armv7a_cache)
 {
-	if (armv7a_cache->ctype == -1) {
+	int cl;
+
+	if (armv7a_cache->info == -1) {
 		command_print(cmd_ctx, "cache not yet identified");
 		return ERROR_OK;
 	}
 
-	command_print(cmd_ctx,
-		"D-Cache: linelen %" PRIi32 ", associativity %" PRIi32 ", nsets %" PRIi32 ", cachesize %" PRId32 " KBytes",
-		armv7a_cache->d_u_size.linelen,
-		armv7a_cache->d_u_size.associativity,
-		armv7a_cache->d_u_size.nsets,
-		armv7a_cache->d_u_size.cachesize);
+	for (cl = 0; cl < armv7a_cache->loc; cl++) {
+		struct armv7a_arch_cache *arch = &(armv7a_cache->arch[cl]);
+
+		if (arch->ctype & 1) {
+			command_print(cmd_ctx,
+				"L%d I-Cache: linelen %" PRIi32
+				", associativity %" PRIi32
+				", nsets %" PRIi32
+				", cachesize %" PRId32 " KBytes",
+				cl+1,
+				arch->i_size.linelen,
+				arch->i_size.associativity,
+				arch->i_size.nsets,
+				arch->i_size.cachesize);
+		}
 
-	command_print(cmd_ctx,
-		"I-Cache: linelen %" PRIi32 ", associativity %" PRIi32 ", nsets %" PRIi32 ", cachesize %" PRId32 " KBytes",
-		armv7a_cache->i_size.linelen,
-		armv7a_cache->i_size.associativity,
-		armv7a_cache->i_size.nsets,
-		armv7a_cache->i_size.cachesize);
+		if (arch->ctype >= 2) {
+			command_print(cmd_ctx,
+				"L%d D-Cache: linelen %" PRIi32
+				", associativity %" PRIi32
+				", nsets %" PRIi32
+				", cachesize %" PRId32 " KBytes",
+				cl+1,
+				arch->d_u_size.linelen,
+				arch->d_u_size.associativity,
+				arch->d_u_size.nsets,
+				arch->d_u_size.cachesize);
+		}
+	}
 
 	return ERROR_OK;
 }
@@ -457,7 +475,7 @@ int armv7a_handle_cache_info_command(struct command_context *cmd_ctx,
 	struct armv7a_l2x_cache *l2x_cache = (struct armv7a_l2x_cache *)
 		(armv7a_cache->outer_cache);
 
-	if (armv7a_cache->ctype == -1) {
+	if (armv7a_cache->info == -1) {
 		command_print(cmd_ctx, "cache not yet identified");
 		return ERROR_OK;
 	}
@@ -517,17 +535,61 @@ done:
 
 }
 
+static int get_cache_info(struct arm_dpm *dpm, int cl, int ct, uint32_t *cache_reg)
+{
+	int retval = ERROR_OK;
+
+	/*  select cache level */
+	retval = dpm->instr_write_data_r0(dpm,
+			ARMV4_5_MCR(15, 2, 0, 0, 0, 0),
+			(cl << 1) | (ct == 1 ? 1 : 0));
+	if (retval != ERROR_OK)
+		goto done;
+
+	retval = dpm->instr_read_data_r0(dpm,
+			ARMV4_5_MRC(15, 1, 0, 0, 0, 0),
+			cache_reg);
+ done:
+	return retval;
+}
+
+static struct armv7a_cachesize decode_cache_reg(uint32_t cache_reg)
+{
+	struct armv7a_cachesize size;
+	int i = 0;
+
+	size.linelen = 16 << (cache_reg & 0x7);
+	size.associativity = ((cache_reg >> 3) & 0x3ff) + 1;
+	size.nsets = ((cache_reg >> 13) & 0x7fff) + 1;
+	size.cachesize = size.linelen * size.associativity * size.nsets / 1024;
+
+	/*  compute info for set way operation on cache */
+	size.index_shift = (cache_reg & 0x7) + 4;
+	size.index = (cache_reg >> 13) & 0x7fff;
+	size.way = ((cache_reg >> 3) & 0x3ff);
+
+	while (((size.way << i) & 0x80000000) == 0)
+		i++;
+	size.way_shift = i;
+
+	return size;
+}
+
 int armv7a_identify_cache(struct target *target)
 {
 	/*  read cache descriptor */
 	int retval = ERROR_FAIL;
 	struct armv7a_common *armv7a = target_to_armv7a(target);
 	struct arm_dpm *dpm = armv7a->arm.dpm;
-	uint32_t cache_selected, clidr, ctr;
-	uint32_t cache_i_reg, cache_d_reg;
-	struct armv7a_cache_common *cache = &(armv7a->armv7a_mmu.armv7a_cache);
+	uint32_t csselr, clidr, ctr;
+	uint32_t cache_reg;
+	int cl, ctype;
+	struct armv7a_cache_common *cache =
+		&(armv7a->armv7a_mmu.armv7a_cache);
+
 	if (!armv7a->is_armv7r)
 		armv7a_read_ttbcr(target);
+
 	retval = dpm->prepare(dpm);
 	if (retval != ERROR_OK)
 		goto done;
@@ -552,120 +614,79 @@ int armv7a_identify_cache(struct target *target)
 			&clidr);
 	if (retval != ERROR_OK)
 		goto done;
-	clidr = (clidr & 0x7000000) >> 23;
-	LOG_INFO("number of cache level %" PRIx32, (uint32_t)(clidr / 2));
-	if ((clidr / 2) > 1) {
-		/* FIXME not supported present in cortex A8 and later */
-		/*  in cortex A7, A15 */
-		LOG_ERROR("cache l2 present :not supported");
-	}
-	/*  retrieve selected cache
+
+	cache->loc = (clidr & 0x7000000) >> 24;
+	LOG_DEBUG("Number of cache levels to PoC %" PRId32, cache->loc);
+
+	/*  retrieve selected cache for later restore
 	 *  MRC p15, 2,<Rd>, c0, c0, 0; Read CSSELR */
 	retval = dpm->instr_read_data_r0(dpm,
 			ARMV4_5_MRC(15, 2, 0, 0, 0, 0),
-			&cache_selected);
+			&csselr);
 	if (retval != ERROR_OK)
 		goto done;
 
-	retval = armv7a->arm.mrc(target, 15,
-			2, 0,	/* op1, op2 */
-			0, 0,	/* CRn, CRm */
-			&cache_selected);
-	if (retval != ERROR_OK)
-		goto done;
-	/* select instruction cache
-	 *  MCR p15, 2,<Rd>, c0, c0, 0; Write CSSELR
-	 *  [0]  : 1 instruction cache selection , 0 data cache selection */
-	retval = dpm->instr_write_data_r0(dpm,
-			ARMV4_5_MRC(15, 2, 0, 0, 0, 0),
-			1);
-	if (retval != ERROR_OK)
-		goto done;
-
-	/* read CCSIDR
-	 * MRC P15,1,<RT>,C0, C0,0 ;on cortex A9 read CCSIDR
-	 * [2:0] line size  001 eight word per line
-	 * [27:13] NumSet 0x7f 16KB, 0xff 32Kbytes, 0x1ff 64Kbytes */
-	retval = dpm->instr_read_data_r0(dpm,
-			ARMV4_5_MRC(15, 1, 0, 0, 0, 0),
-			&cache_i_reg);
-	if (retval != ERROR_OK)
-		goto done;
+	/* retrieve all available inner caches */
+	for (cl = 0; cl < cache->loc; clidr >>= 3, cl++) {
+
+		/* isolate cache type at current level */
+		ctype = clidr & 7;
+
+		/* skip reserved values */
+		if (ctype > CACHE_LEVEL_HAS_UNIFIED_CACHE)
+			continue;
+
+		/* separate d or unified d/i cache at this level ? */
+		if (ctype & (CACHE_LEVEL_HAS_UNIFIED_CACHE | CACHE_LEVEL_HAS_D_CACHE)) {
+			/* retrieve d-cache info */
+			retval = get_cache_info(dpm, cl, 0, &cache_reg);
+			if (retval != ERROR_OK)
+				goto done;
+			cache->arch[cl].d_u_size = decode_cache_reg(cache_reg);
+
+			LOG_DEBUG("data/unified cache index %d << %d, way %d << %d",
+					cache->arch[cl].d_u_size.index,
+					cache->arch[cl].d_u_size.index_shift,
+					cache->arch[cl].d_u_size.way,
+					cache->arch[cl].d_u_size.way_shift);
+
+			LOG_DEBUG("cacheline %d bytes %d KBytes asso %d ways",
+					cache->arch[cl].d_u_size.linelen,
+					cache->arch[cl].d_u_size.cachesize,
+					cache->arch[cl].d_u_size.associativity);
+		}
 
-	/*  select data cache*/
-	retval = dpm->instr_write_data_r0(dpm,
-			ARMV4_5_MRC(15, 2, 0, 0, 0, 0),
-			0);
-	if (retval != ERROR_OK)
-		goto done;
+		/* separate i-cache at this level ? */
+		if (ctype & CACHE_LEVEL_HAS_I_CACHE) {
+			/* retrieve i-cache info */
+			retval = get_cache_info(dpm, cl, 1, &cache_reg);
+			if (retval != ERROR_OK)
+				goto done;
+			cache->arch[cl].i_size = decode_cache_reg(cache_reg);
+
+			LOG_DEBUG("instruction cache index %d << %d, way %d << %d",
+					cache->arch[cl].i_size.index,
+					cache->arch[cl].i_size.index_shift,
+					cache->arch[cl].i_size.way,
+					cache->arch[cl].i_size.way_shift);
+
+			LOG_DEBUG("cacheline %d bytes %d KBytes asso %d ways",
+					cache->arch[cl].i_size.linelen,
+					cache->arch[cl].i_size.cachesize,
+					cache->arch[cl].i_size.associativity);
+		}
 
-	retval = dpm->instr_read_data_r0(dpm,
-			ARMV4_5_MRC(15, 1, 0, 0, 0, 0),
-			&cache_d_reg);
-	if (retval != ERROR_OK)
-		goto done;
+		cache->arch[cl].ctype = ctype;
+	}
 
 	/*  restore selected cache  */
 	dpm->instr_write_data_r0(dpm,
 		ARMV4_5_MRC(15, 2, 0, 0, 0, 0),
-		cache_selected);
+		csselr);
 
 	if (retval != ERROR_OK)
 		goto done;
-	dpm->finish(dpm);
 
-	/* put fake type */
-	cache->d_u_size.linelen = 16 << (cache_d_reg & 0x7);
-	cache->d_u_size.cachesize = (((cache_d_reg >> 13) & 0x7fff)+1)/8;
-	cache->d_u_size.nsets = (cache_d_reg >> 13) & 0x7fff;
-	cache->d_u_size.associativity = ((cache_d_reg >> 3) & 0x3ff) + 1;
-	/*  compute info for set way operation on cache */
-	cache->d_u_size.index_shift = (cache_d_reg & 0x7) + 4;
-	cache->d_u_size.index = (cache_d_reg >> 13) & 0x7fff;
-	cache->d_u_size.way = ((cache_d_reg >> 3) & 0x3ff);
-	cache->d_u_size.way_shift = cache->d_u_size.way + 1;
-	{
-		int i = 0;
-		while (((cache->d_u_size.way_shift >> i) & 1) != 1)
-			i++;
-		cache->d_u_size.way_shift = 32-i;
-	}
-#if 0
-	LOG_INFO("data cache index %d << %d, way %d << %d",
-			cache->d_u_size.index, cache->d_u_size.index_shift,
-			cache->d_u_size.way,
-			cache->d_u_size.way_shift);
-
-	LOG_INFO("data cache %d bytes %d KBytes asso %d ways",
-			cache->d_u_size.linelen,
-			cache->d_u_size.cachesize,
-			cache->d_u_size.associativity);
-#endif
-	cache->i_size.linelen = 16 << (cache_i_reg & 0x7);
-	cache->i_size.associativity = ((cache_i_reg >> 3) & 0x3ff) + 1;
-	cache->i_size.nsets = (cache_i_reg >> 13) & 0x7fff;
-	cache->i_size.cachesize = (((cache_i_reg >> 13) & 0x7fff)+1)/8;
-	/*  compute info for set way operation on cache */
-	cache->i_size.index_shift = (cache_i_reg & 0x7) + 4;
-	cache->i_size.index = (cache_i_reg >> 13) & 0x7fff;
-	cache->i_size.way = ((cache_i_reg >> 3) & 0x3ff);
-	cache->i_size.way_shift = cache->i_size.way + 1;
-	{
-		int i = 0;
-		while (((cache->i_size.way_shift >> i) & 1) != 1)
-			i++;
-		cache->i_size.way_shift = 32-i;
-	}
-#if 0
-	LOG_INFO("instruction cache index %d << %d, way %d << %d",
-			cache->i_size.index, cache->i_size.index_shift,
-			cache->i_size.way, cache->i_size.way_shift);
-
-	LOG_INFO("instruction cache %d bytes %d KBytes asso %d ways",
-			cache->i_size.linelen,
-			cache->i_size.cachesize,
-			cache->i_size.associativity);
-#endif
 	/*  if no l2 cache initialize l1 data cache flush function function */
 	if (armv7a->armv7a_mmu.armv7a_cache.flush_all_data_cache == NULL) {
 		armv7a->armv7a_mmu.armv7a_cache.display_cache_info =
@@ -673,8 +694,8 @@ int armv7a_identify_cache(struct target *target)
 		armv7a->armv7a_mmu.armv7a_cache.flush_all_data_cache =
 			armv7a_cache_auto_flush_all_data;
 	}
-	armv7a->armv7a_mmu.armv7a_cache.ctype = 0;
 
+	armv7a->armv7a_mmu.armv7a_cache.info = 1;
 done:
 	dpm->finish(dpm);
 	armv7a_read_mpidr(target);
@@ -691,7 +712,7 @@ int armv7a_init_arch_info(struct target *target, struct armv7a_common *armv7a)
 	armv7a->arm.target = target;
 	armv7a->arm.common_magic = ARM_COMMON_MAGIC;
 	armv7a->common_magic = ARMV7_COMMON_MAGIC;
-	armv7a->armv7a_mmu.armv7a_cache.ctype = -1;
+	armv7a->armv7a_mmu.armv7a_cache.info = -1;
 	armv7a->armv7a_mmu.armv7a_cache.outer_cache = NULL;
 	armv7a->armv7a_mmu.armv7a_cache.flush_all_data_cache = NULL;
 	armv7a->armv7a_mmu.armv7a_cache.display_cache_info = NULL;