cortex_a: Add support for A15 MPCore

Added Cortex-A15 support for DAP AHB-AP init code as per ADI V5 spec.
Also added changes to make the APB MEM-AP to work with A15.
Made the the cortex_a target code  generic to work with A8, A9
and A15 single core or multicore implementation. Added armv7a code
for os_border calculation to work for known A8, A9 and A15
platforms based on the ARM DDI 0344H, ARM DDI 0407F, ARM DDI 0406C
ARMV7A architecture docs.

Change-Id: Ib2803ab62588bf40f1ae4b9192b619af31525a1a
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Reviewed-on: http://openocd.zylin.com/1601
Tested-by: jenkins
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>

5 files changed, 183 insertions, 19 deletions

diff --git a/src/target/arm_adi_v5.c b/src/target/arm_adi_v5.c
index c76cc69..7bb2a0b 100644
--- a/src/target/arm_adi_v5.c
+++ b/src/target/arm_adi_v5.c
@@ -1339,7 +1339,12 @@ static int dap_rom_display(struct command_context *cmd_ctx,
 				type = "Cortex-A9 Debug";
 				full = "(Debug Unit)";
 				break;
+			case 0x4af:
+				type = "Cortex-A15 Debug";
+				full = "(Debug Unit)";
+				break;
 			default:
+				LOG_DEBUG("Unrecognized Part number 0x%" PRIx32, part_num);
 				type = "-*- unrecognized -*-";
 				full = "";
 				break;
@@ -1408,9 +1413,9 @@ static int dap_info_command(struct command_context *cmd_ctx,
 		command_print(cmd_ctx, "No AP found at this ap 0x%x", ap);
 
 	romtable_present = ((mem_ap) && (dbgbase != 0xFFFFFFFF));
-	if (romtable_present) {
+	if (romtable_present)
 		dap_rom_display(cmd_ctx, dap, ap, dbgbase, 0);
-	} else
+	else
 		command_print(cmd_ctx, "\tNo ROM table present");
 	dap_ap_select(dap, ap_old);
 
diff --git a/src/target/armv7a.c b/src/target/armv7a.c
index bf474d3..57b8799 100644
--- a/src/target/armv7a.c
+++ b/src/target/armv7a.c
@@ -88,11 +88,50 @@ done:
 	/* (void) */ dpm->finish(dpm);
 }
 
+
+/*  retrieve main id register  */
+static int armv7a_read_midr(struct target *target)
+{
+	int retval = ERROR_FAIL;
+	struct armv7a_common *armv7a = target_to_armv7a(target);
+	struct arm_dpm *dpm = armv7a->arm.dpm;
+	uint32_t midr;
+	retval = dpm->prepare(dpm);
+	if (retval != ERROR_OK)
+		goto done;
+	/* MRC p15,0,<Rd>,c0,c0,0; read main id register*/
+
+	retval = dpm->instr_read_data_r0(dpm,
+			ARMV4_5_MRC(15, 0, 0, 0, 0, 0),
+			&midr);
+	if (retval != ERROR_OK)
+		goto done;
+
+	armv7a->rev = (midr & 0xf);
+	armv7a->partnum = (midr >> 4) & 0xfff;
+	armv7a->arch = (midr >> 16) & 0xf;
+	armv7a->variant = (midr >> 20) & 0xf;
+	armv7a->implementor = (midr >> 24) & 0xff;
+	LOG_INFO("%s rev %" PRIx32 ", partnum %" PRIx32 ", arch %" PRIx32
+			 ", variant %" PRIx32 ", implementor %" PRIx32,
+		 target->cmd_name,
+		 armv7a->rev,
+		 armv7a->partnum,
+		 armv7a->arch,
+		 armv7a->variant,
+		 armv7a->implementor);
+
+done:
+	dpm->finish(dpm);
+	return retval;
+}
+
 static int armv7a_read_ttbcr(struct target *target)
 {
 	struct armv7a_common *armv7a = target_to_armv7a(target);
 	struct arm_dpm *dpm = armv7a->arm.dpm;
 	uint32_t ttbcr;
+	uint32_t ttbr0, ttbr1;
 	int retval = dpm->prepare(dpm);
 	if (retval != ERROR_OK)
 		goto done;
@@ -102,27 +141,55 @@ static int armv7a_read_ttbcr(struct target *target)
 			&ttbcr);
 	if (retval != ERROR_OK)
 		goto done;
+
+	retval = dpm->instr_read_data_r0(dpm,
+			ARMV4_5_MRC(15, 0, 0, 2, 0, 0),
+			&ttbr0);
+	if (retval != ERROR_OK)
+		goto done;
+
+	retval = dpm->instr_read_data_r0(dpm,
+			ARMV4_5_MRC(15, 0, 0, 2, 0, 1),
+			&ttbr1);
+	if (retval != ERROR_OK)
+		goto done;
+
+	LOG_INFO("ttbcr %" PRIx32 "ttbr0 %" PRIx32 "ttbr1 %" PRIx32, ttbcr, ttbr0, ttbr1);
+
 	armv7a->armv7a_mmu.ttbr1_used = ((ttbcr & 0x7) != 0) ? 1 : 0;
-	armv7a->armv7a_mmu.ttbr0_mask  = 7 << (32 - ((ttbcr & 0x7)));
-#if 0
-	LOG_INFO("ttb1 %s ,ttb0_mask %x",
-		armv7a->armv7a_mmu.ttbr1_used ? "used" : "not used",
-		armv7a->armv7a_mmu.ttbr0_mask);
-#endif
-	if (armv7a->armv7a_mmu.ttbr1_used == 1) {
-		LOG_INFO("SVC access above %" PRIx32,
-			 (uint32_t)(0xffffffff & armv7a->armv7a_mmu.ttbr0_mask));
-		armv7a->armv7a_mmu.os_border = 0xffffffff & armv7a->armv7a_mmu.ttbr0_mask;
+	armv7a->armv7a_mmu.ttbr0_mask = 0;
+
+	retval = armv7a_read_midr(target);
+	if (retval != ERROR_OK)
+		goto done;
+
+	if (armv7a->partnum & 0xf) {
+		/*
+		 * ARM Architecture Reference Manual (ARMv7-A and ARMv7-Redition),
+		 * document # ARM DDI 0406C
+		 */
+		armv7a->armv7a_mmu.ttbr0_mask  = 1 << (14 - ((ttbcr & 0x7)));
 	} else {
+		/*  ARM DDI 0344H , ARM DDI 0407F */
+		armv7a->armv7a_mmu.ttbr0_mask  = 7 << (32 - ((ttbcr & 0x7)));
 		/*  fix me , default is hard coded LINUX border  */
 		armv7a->armv7a_mmu.os_border = 0xc0000000;
 	}
+
+	LOG_DEBUG("ttbr1 %s, ttbr0_mask %" PRIx32,
+		  armv7a->armv7a_mmu.ttbr1_used ? "used" : "not used",
+		  armv7a->armv7a_mmu.ttbr0_mask);
+
+	if (armv7a->armv7a_mmu.ttbr1_used == 1) {
+		LOG_INFO("SVC access above %" PRIx32,
+			(0xffffffff & armv7a->armv7a_mmu.ttbr0_mask));
+		armv7a->armv7a_mmu.os_border = 0xffffffff & armv7a->armv7a_mmu.ttbr0_mask;
+	}
 done:
 	dpm->finish(dpm);
 	return retval;
 }
 
-
 /*  method adapted to cortex A : reused arm v4 v5 method*/
 int armv7a_mmu_translate_va(struct target *target,  uint32_t va, uint32_t *val)
 {
diff --git a/src/target/armv7a.h b/src/target/armv7a.h
index 341114b..4341aca 100644
--- a/src/target/armv7a.h
+++ b/src/target/armv7a.h
@@ -77,6 +77,7 @@ struct armv7a_cache_common {
 
 struct armv7a_mmu_common {
 	/* following field mmu working way */
+	int32_t ttbr0_used;
 	int32_t ttbr1_used; /*  -1 not initialized, 0 no ttbr1 1 ttbr1 used and  */
 	uint32_t ttbr0_mask;/*  masked to be used  */
 	uint32_t os_border;
@@ -105,6 +106,11 @@ struct armv7a_common {
 	uint8_t cluster_id;
 	uint8_t cpu_id;
 	bool is_armv7r;
+	uint32_t rev;
+	uint32_t partnum;
+	uint32_t arch;
+	uint32_t variant;
+	uint32_t implementor;
 
 	/* cache specific to V7 Memory Management Unit compatible with v4_5*/
 	struct armv7a_mmu_common armv7a_mmu;
diff --git a/src/target/cortex_a.c b/src/target/cortex_a.c
index 0393a44..3075055 100644
--- a/src/target/cortex_a.c
+++ b/src/target/cortex_a.c
@@ -20,6 +20,9 @@
  *   Copyright (C) Broadcom 2012                                           *
  *   ehunter@broadcom.com : Cortex R4 support                              *
  *                                                                         *
+ *   Copyright (C) 2013 Kamal Dasu                                         *
+ *   kdasu.kdev@gmail.com                                                  *
+ *                                                                         *
  *   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     *
@@ -164,12 +167,11 @@ static int cortex_a_mmu_modify(struct target *target, int enable)
 /*
  * Cortex-A Basic debug access, very low level assumes state is saved
  */
-static int cortex_a_init_debug_access(struct target *target)
+static int cortex_a8_init_debug_access(struct target *target)
 {
 	struct armv7a_common *armv7a = target_to_armv7a(target);
 	struct adiv5_dap *swjdp = armv7a->arm.dap;
 	int retval;
-	uint32_t dummy;
 
 	LOG_DEBUG(" ");
 
@@ -185,12 +187,57 @@ static int cortex_a_init_debug_access(struct target *target)
 			LOG_USER(
 				"Locking debug access failed on first, but succeeded on second try.");
 	}
+
+	return retval;
+}
+
+/*
+ * Cortex-A Basic debug access, very low level assumes state is saved
+ */
+static int cortex_a_init_debug_access(struct target *target)
+{
+	struct armv7a_common *armv7a = target_to_armv7a(target);
+	struct adiv5_dap *swjdp = armv7a->arm.dap;
+	int retval;
+	uint32_t dbg_osreg;
+	uint32_t cortex_part_num;
+	struct cortex_a_common *cortex_a = target_to_cortex_a(target);
+
+	LOG_DEBUG(" ");
+	cortex_part_num = (cortex_a->cpuid & CORTEX_A_MIDR_PARTNUM_MASK) >>
+		CORTEX_A_MIDR_PARTNUM_SHIFT;
+
+	switch (cortex_part_num) {
+	case CORTEX_A15_PARTNUM:
+		retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+						    armv7a->debug_base + CPUDBG_OSLSR,
+						    &dbg_osreg);
+		if (retval != ERROR_OK)
+			return retval;
+
+		LOG_DEBUG("DBGOSLSR  0x%" PRIx32, dbg_osreg);
+
+		if (dbg_osreg & CPUDBG_OSLAR_LK_MASK)
+			/* Unlocking the DEBUG OS registers for modification */
+			retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
+							     armv7a->debug_base + CPUDBG_OSLAR,
+							     0);
+		break;
+
+	case CORTEX_A8_PARTNUM:
+	case CORTEX_A9_PARTNUM:
+	default:
+		retval = cortex_a8_init_debug_access(target);
+	}
+
 	if (retval != ERROR_OK)
 		return retval;
 	/* Clear Sticky Power Down status Bit in PRSR to enable access to
 	   the registers in the Core Power Domain */
 	retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
-			armv7a->debug_base + CPUDBG_PRSR, &dummy);
+			armv7a->debug_base + CPUDBG_PRSR, &dbg_osreg);
+	LOG_DEBUG("target->coreid %d DBGPRSR  0x%x ", target->coreid, dbg_osreg);
+
 	if (retval != ERROR_OK)
 		return retval;
 
@@ -1799,6 +1846,7 @@ static int cortex_a_write_apb_ab_memory(struct target *target,
 	uint32_t dscr;
 	uint8_t *tmp_buff = NULL;
 
+
 	LOG_DEBUG("Writing APB-AP memory address 0x%" PRIx32 " size %"  PRIu32 " count%"  PRIu32,
 			  address, size, count);
 	if (target->state != TARGET_HALTED) {
@@ -1846,7 +1894,6 @@ static int cortex_a_write_apb_ab_memory(struct target *target,
 	/* If end of write is not aligned, or the write is less than 4 bytes */
 	if ((end_byte != 0) ||
 		((total_u32 == 1) && (total_bytes != 4))) {
-
 		/* Read the last word to avoid corruption during 32 bit write */
 		int mem_offset = (total_u32-1) * 4;
 		retval = cortex_a_read_apb_ab_memory(target, (address & ~0x3) + mem_offset, 4, 1, &tmp_buff[mem_offset]);
@@ -2163,7 +2210,8 @@ static int cortex_a_read_memory(struct target *target, uint32_t address,
 				  virt, phys);
 			address = phys;
 		}
-		retval = cortex_a_read_phys_memory(target, address, size, count, buffer);
+		retval = cortex_a_read_phys_memory(target, address, size,
+			    count, buffer);
 	} else {
 		if (mmu_enabled) {
 			retval = cortex_a_check_address(target, address);
@@ -2363,7 +2411,7 @@ static int cortex_a_examine_first(struct target *target)
 	struct adiv5_dap *swjdp = armv7a->arm.dap;
 	int i;
 	int retval = ERROR_OK;
-	uint32_t didr, ctypr, ttypr, cpuid;
+	uint32_t didr, ctypr, ttypr, cpuid, dbg_osreg;
 
 	/* We do one extra read to ensure DAP is configured,
 	 * we call ahbap_debugport_init(swjdp) instead
@@ -2447,6 +2495,31 @@ static int cortex_a_examine_first(struct target *target)
 	LOG_DEBUG("ttypr = 0x%08" PRIx32, ttypr);
 	LOG_DEBUG("didr = 0x%08" PRIx32, didr);
 
+	cortex_a->cpuid = cpuid;
+	cortex_a->ctypr = ctypr;
+	cortex_a->ttypr = ttypr;
+	cortex_a->didr = didr;
+
+	/* Unlocking the debug registers */
+	if ((cpuid & CORTEX_A_MIDR_PARTNUM_MASK) >> CORTEX_A_MIDR_PARTNUM_SHIFT ==
+		CORTEX_A15_PARTNUM) {
+
+		retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
+						     armv7a->debug_base + CPUDBG_OSLAR,
+						     0);
+
+		if (retval != ERROR_OK)
+			return retval;
+
+	}
+	retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+					    armv7a->debug_base + CPUDBG_PRSR, &dbg_osreg);
+
+	if (retval != ERROR_OK)
+		return retval;
+
+	LOG_DEBUG("target->coreid %d DBGPRSR  0x%" PRIx32, target->coreid, dbg_osreg);
+
 	armv7a->arm.core_type = ARM_MODE_MON;
 	retval = cortex_a_dpm_setup(cortex_a, didr);
 	if (retval != ERROR_OK)
diff --git a/src/target/cortex_a.h b/src/target/cortex_a.h
index 7b56fea..043d96f 100644
--- a/src/target/cortex_a.h
+++ b/src/target/cortex_a.h
@@ -33,12 +33,20 @@
 #include "armv7a.h"
 
 #define CORTEX_A_COMMON_MAGIC 0x411fc082
+#define CORTEX_A15_COMMON_MAGIC 0x413fc0f1
+
+#define CORTEX_A8_PARTNUM 0xc08
+#define CORTEX_A9_PARTNUM 0xc09
+#define CORTEX_A15_PARTNUM 0xc0f
+#define CORTEX_A_MIDR_PARTNUM_MASK 0x0000fff0
+#define CORTEX_A_MIDR_PARTNUM_SHIFT 4
 
 #define CPUDBG_CPUID	0xD00
 #define CPUDBG_CTYPR	0xD04
 #define CPUDBG_TTYPR	0xD0C
 #define CPUDBG_LOCKACCESS 0xFB0
 #define CPUDBG_LOCKSTATUS 0xFB4
+#define CPUDBG_OSLAR_LK_MASK (1 << 1)
 
 #define BRP_NORMAL 0
 #define BRP_CONTEXT 1
@@ -76,6 +84,11 @@ struct cortex_a_common {
 	/* Use cortex_a_read_regs_through_mem for fast register reads */
 	int fast_reg_read;
 
+	uint32_t cpuid;
+	uint32_t ctypr;
+	uint32_t ttypr;
+	uint32_t didr;
+
 	struct armv7a_common armv7a_common;
 
 };