cfi: fix error propagation

any read/write operation to memory can fail.

block write algorithm error propagation was broken
in that it would continue after an error was reported
writing data to ram or the algorithm failing.

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

2 files changed, 341 insertions, 118 deletions

diff --git a/src/flash/nor/cfi.c b/src/flash/nor/cfi.c
index f0ab332f..f911bb70 100644
--- a/src/flash/nor/cfi.c
+++ b/src/flash/nor/cfi.c
@@ -146,37 +146,45 @@ static int cfi_send_command(struct flash_bank *bank, uint8_t cmd, uint32_t addre
  * flash banks are expected to be made of similar chips
  * the query result should be the same for all
  */
-static uint8_t cfi_query_u8(struct flash_bank *bank, int sector, uint32_t offset)
+static int cfi_query_u8(struct flash_bank *bank, int sector, uint32_t offset, uint8_t *val)
 {
 	struct target *target = bank->target;
 	uint8_t data[CFI_MAX_BUS_WIDTH];
 
-	target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 1, data);
+	int retval;
+	retval = target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 1, data);
+	if (retval != ERROR_OK)
+		return retval;
 
 	if (bank->target->endianness == TARGET_LITTLE_ENDIAN)
-		return data[0];
+		*val = data[0];
 	else
-		return data[bank->bus_width - 1];
+		*val = data[bank->bus_width - 1];
+
+	return ERROR_OK;
 }
 
 /* read unsigned 8-bit value from the bank
  * in case of a bank made of multiple chips,
  * the individual values are ORed
  */
-static uint8_t cfi_get_u8(struct flash_bank *bank, int sector, uint32_t offset)
+static int cfi_get_u8(struct flash_bank *bank, int sector, uint32_t offset, uint8_t *val)
 {
 	struct target *target = bank->target;
 	uint8_t data[CFI_MAX_BUS_WIDTH];
 	int i;
 
-	target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 1, data);
+	int retval;
+	retval = target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 1, data);
+	if (retval != ERROR_OK)
+		return retval;
 
 	if (bank->target->endianness == TARGET_LITTLE_ENDIAN)
 	{
 		for (i = 0; i < bank->bus_width / bank->chip_width; i++)
 			data[0] |= data[i];
 
-		return data[0];
+		*val = data[0];
 	}
 	else
 	{
@@ -184,53 +192,75 @@ static uint8_t cfi_get_u8(struct flash_bank *bank, int sector, uint32_t offset)
 		for (i = 0; i < bank->bus_width / bank->chip_width; i++)
 			value |= data[bank->bus_width - 1 - i];
 
-		return value;
+		*val = value;
 	}
+	return ERROR_OK;
 }
 
-static uint16_t cfi_query_u16(struct flash_bank *bank, int sector, uint32_t offset)
+static int cfi_query_u16(struct flash_bank *bank, int sector, uint32_t offset, uint16_t *val)
 {
 	struct target *target = bank->target;
 	struct cfi_flash_bank *cfi_info = bank->driver_priv;
 	uint8_t data[CFI_MAX_BUS_WIDTH * 2];
+	int retval;
 
 	if (cfi_info->x16_as_x8)
 	{
 		uint8_t i;
 		for (i = 0;i < 2;i++)
-			target_read_memory(target, flash_address(bank, sector, offset + i), bank->bus_width, 1,
+		{
+			retval = target_read_memory(target, flash_address(bank, sector, offset + i), bank->bus_width, 1,
 				&data[i*bank->bus_width]);
+			if (retval != ERROR_OK)
+				return retval;
+		}
+	} else
+	{
+		retval = target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 2, data);
+		if (retval != ERROR_OK)
+			return retval;
 	}
-	else
-		target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 2, data);
 
 	if (bank->target->endianness == TARGET_LITTLE_ENDIAN)
-		return data[0] | data[bank->bus_width] << 8;
+		*val = data[0] | data[bank->bus_width] << 8;
 	else
-		return data[bank->bus_width - 1] | data[(2 * bank->bus_width) - 1] << 8;
+		*val = data[bank->bus_width - 1] | data[(2 * bank->bus_width) - 1] << 8;
+
+	return ERROR_OK;
 }
 
-static uint32_t cfi_query_u32(struct flash_bank *bank, int sector, uint32_t offset)
+static int cfi_query_u32(struct flash_bank *bank, int sector, uint32_t offset, uint32_t *val)
 {
 	struct target *target = bank->target;
 	struct cfi_flash_bank *cfi_info = bank->driver_priv;
 	uint8_t data[CFI_MAX_BUS_WIDTH * 4];
+	int retval;
 
 	if (cfi_info->x16_as_x8)
 	{
 		uint8_t i;
 		for (i = 0;i < 4;i++)
-			target_read_memory(target, flash_address(bank, sector, offset + i), bank->bus_width, 1,
+		{
+			retval = target_read_memory(target, flash_address(bank, sector, offset + i), bank->bus_width, 1,
 				&data[i*bank->bus_width]);
+			if (retval != ERROR_OK)
+				return retval;
+		}
 	}
 	else
-		target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 4, data);
+	{
+		retval = target_read_memory(target, flash_address(bank, sector, offset), bank->bus_width, 4, data);
+		if (retval != ERROR_OK)
+			return retval;
+	}
 
 	if (bank->target->endianness == TARGET_LITTLE_ENDIAN)
-		return data[0] | data[bank->bus_width] << 8 | data[bank->bus_width * 2] << 16 | data[bank->bus_width * 3] << 24;
+		*val = data[0] | data[bank->bus_width] << 8 | data[bank->bus_width * 2] << 16 | data[bank->bus_width * 3] << 24;
 	else
-		return data[bank->bus_width - 1] | data[(2* bank->bus_width) - 1] << 8 |
+		*val = data[bank->bus_width - 1] | data[(2* bank->bus_width) - 1] << 8 |
 				data[(3 * bank->bus_width) - 1] << 16 | data[(4 * bank->bus_width) - 1] << 24;
+
+	return ERROR_OK;
 }
 
 static int cfi_reset(struct flash_bank *bank)
@@ -275,13 +305,27 @@ static void cfi_intel_clear_status_register(struct flash_bank *bank)
 	cfi_send_command(bank, 0x50, flash_address(bank, 0, 0x0));
 }
 
-static uint8_t cfi_intel_wait_status_busy(struct flash_bank *bank, int timeout)
+static int cfi_intel_wait_status_busy(struct flash_bank *bank, int timeout, uint8_t *val)
 {
 	uint8_t status;
 
-	while ((!((status = cfi_get_u8(bank, 0, 0x0)) & 0x80)) && (timeout-- > 0))
+	int retval = ERROR_OK;
+
+	for (;;)
 	{
-		LOG_DEBUG("status: 0x%x", status);
+		if (timeout-- < 0)
+		{
+		  LOG_ERROR("timeout while waiting for WSM to become ready");
+		  return ERROR_FAIL;
+		}
+
+		retval = cfi_get_u8(bank, 0, 0x0, &status);
+		if (retval != ERROR_OK)
+			return retval;
+
+		if (status & 0x80)
+			break;
+
 		alive_sleep(1);
 	}
 
@@ -290,11 +334,7 @@ static uint8_t cfi_intel_wait_status_busy(struct flash_bank *bank, int timeout)
 
 	LOG_DEBUG("status: 0x%x", status);
 
-	if ((status & 0x80) != 0x80)
-	{
-		LOG_ERROR("timeout while waiting for WSM to become ready");
-	}
-	else if (status != 0x80)
+	if (status != 0x80)
 	{
 		LOG_ERROR("status register: 0x%x", status);
 		if (status & 0x2)
@@ -311,24 +351,38 @@ static uint8_t cfi_intel_wait_status_busy(struct flash_bank *bank, int timeout)
 			LOG_ERROR("Block Erase Suspended");
 
 		cfi_intel_clear_status_register(bank);
+
+		retval = ERROR_FAIL;
 	}
 
-	return status;
+	*val = status;
+	return retval;
 }
 
 static int cfi_spansion_wait_status_busy(struct flash_bank *bank, int timeout)
 {
 	uint8_t status, oldstatus;
 	struct cfi_flash_bank *cfi_info = bank->driver_priv;
+	int retval;
 
-	oldstatus = cfi_get_u8(bank, 0, 0x0);
+	retval = cfi_get_u8(bank, 0, 0x0, &oldstatus);
+	if (retval != ERROR_OK)
+		return retval;
 
 	do {
-		status = cfi_get_u8(bank, 0, 0x0);
+		retval = cfi_get_u8(bank, 0, 0x0, &status);
+
+		if (retval != ERROR_OK)
+			return retval;
+
 		if ((status ^ oldstatus) & 0x40) {
 			if (status & cfi_info->status_poll_mask & 0x20) {
-				oldstatus = cfi_get_u8(bank, 0, 0x0);
-				status = cfi_get_u8(bank, 0, 0x0);
+				retval = cfi_get_u8(bank, 0, 0x0, &oldstatus);
+				if (retval != ERROR_OK)
+					return retval;
+				retval = cfi_get_u8(bank, 0, 0x0, &status);
+				if (retval != ERROR_OK)
+					return retval;
 				if ((status ^ oldstatus) & 0x40) {
 					LOG_ERROR("dq5 timeout, status: 0x%x", status);
 					return(ERROR_FLASH_OPERATION_FAILED);
@@ -368,9 +422,15 @@ static int cfi_read_intel_pri_ext(struct flash_bank *bank)
 	}
 	cfi_info->pri_ext = pri_ext;
 
-	pri_ext->pri[0] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0);
-	pri_ext->pri[1] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 1);
-	pri_ext->pri[2] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 2);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0, &pri_ext->pri[0]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 1, &pri_ext->pri[1]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 2, &pri_ext->pri[2]);
+	if (retval != ERROR_OK)
+		return retval;
 
 	if ((pri_ext->pri[0] != 'P') || (pri_ext->pri[1] != 'R') || (pri_ext->pri[2] != 'I'))
 	{
@@ -382,36 +442,58 @@ static int cfi_read_intel_pri_ext(struct flash_bank *bank)
 		return ERROR_FLASH_BANK_INVALID;
 	}
 
-	pri_ext->major_version = cfi_query_u8(bank, 0, cfi_info->pri_addr + 3);
-	pri_ext->minor_version = cfi_query_u8(bank, 0, cfi_info->pri_addr + 4);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 3, &pri_ext->major_version);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 4, &pri_ext->minor_version);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("pri: '%c%c%c', version: %c.%c", pri_ext->pri[0], pri_ext->pri[1], pri_ext->pri[2], pri_ext->major_version, pri_ext->minor_version);
 
-	pri_ext->feature_support = cfi_query_u32(bank, 0, cfi_info->pri_addr + 5);
-	pri_ext->suspend_cmd_support = cfi_query_u8(bank, 0, cfi_info->pri_addr + 9);
-	pri_ext->blk_status_reg_mask = cfi_query_u16(bank, 0, cfi_info->pri_addr + 0xa);
+	retval = cfi_query_u32(bank, 0, cfi_info->pri_addr + 5, &pri_ext->feature_support);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 9, &pri_ext->suspend_cmd_support);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u16(bank, 0, cfi_info->pri_addr + 0xa, &pri_ext->blk_status_reg_mask);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("feature_support: 0x%" PRIx32 ", suspend_cmd_support: 0x%x, blk_status_reg_mask: 0x%x",
 		  pri_ext->feature_support,
 		  pri_ext->suspend_cmd_support,
 		  pri_ext->blk_status_reg_mask);
 
-	pri_ext->vcc_optimal = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0xc);
-	pri_ext->vpp_optimal = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0xd);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0xc, &pri_ext->vcc_optimal);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0xd, &pri_ext->vpp_optimal);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("Vcc opt: %x.%x, Vpp opt: %u.%x",
 		  (pri_ext->vcc_optimal & 0xf0) >> 4, pri_ext->vcc_optimal & 0x0f,
 		  (pri_ext->vpp_optimal & 0xf0) >> 4, pri_ext->vpp_optimal & 0x0f);
 
-	pri_ext->num_protection_fields = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0xe);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0xe, &pri_ext->num_protection_fields);
+	if (retval != ERROR_OK)
+		return retval;
 	if (pri_ext->num_protection_fields != 1)
 	{
 		LOG_WARNING("expected one protection register field, but found %i", pri_ext->num_protection_fields);
 	}
 
-	pri_ext->prot_reg_addr = cfi_query_u16(bank, 0, cfi_info->pri_addr + 0xf);
-	pri_ext->fact_prot_reg_size = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0x11);
-	pri_ext->user_prot_reg_size = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0x12);
+	retval = cfi_query_u16(bank, 0, cfi_info->pri_addr + 0xf, &pri_ext->prot_reg_addr);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0x11, &pri_ext->fact_prot_reg_size);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0x12, &pri_ext->user_prot_reg_size);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("protection_fields: %i, prot_reg_addr: 0x%x, factory pre-programmed: %i, user programmable: %i", pri_ext->num_protection_fields, pri_ext->prot_reg_addr, 1 << pri_ext->fact_prot_reg_size, 1 << pri_ext->user_prot_reg_size);
 
@@ -435,9 +517,15 @@ static int cfi_read_spansion_pri_ext(struct flash_bank *bank)
 	}
 	cfi_info->pri_ext = pri_ext;
 
-	pri_ext->pri[0] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0);
-	pri_ext->pri[1] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 1);
-	pri_ext->pri[2] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 2);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0, &pri_ext->pri[0]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 1, &pri_ext->pri[1]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 2, &pri_ext->pri[2]);
+	if (retval != ERROR_OK)
+		return retval;
 
 	if ((pri_ext->pri[0] != 'P') || (pri_ext->pri[1] != 'R') || (pri_ext->pri[2] != 'I'))
 	{
@@ -449,22 +537,48 @@ static int cfi_read_spansion_pri_ext(struct flash_bank *bank)
 		return ERROR_FLASH_BANK_INVALID;
 	}
 
-	pri_ext->major_version = cfi_query_u8(bank, 0, cfi_info->pri_addr + 3);
-	pri_ext->minor_version = cfi_query_u8(bank, 0, cfi_info->pri_addr + 4);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 3, &pri_ext->major_version);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 4, &pri_ext->minor_version);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("pri: '%c%c%c', version: %c.%c", pri_ext->pri[0], pri_ext->pri[1], pri_ext->pri[2], pri_ext->major_version, pri_ext->minor_version);
 
-	pri_ext->SiliconRevision = cfi_query_u8(bank, 0, cfi_info->pri_addr + 5);
-	pri_ext->EraseSuspend    = cfi_query_u8(bank, 0, cfi_info->pri_addr + 6);
-	pri_ext->BlkProt         = cfi_query_u8(bank, 0, cfi_info->pri_addr + 7);
-	pri_ext->TmpBlkUnprotect = cfi_query_u8(bank, 0, cfi_info->pri_addr + 8);
-	pri_ext->BlkProtUnprot   = cfi_query_u8(bank, 0, cfi_info->pri_addr + 9);
-	pri_ext->SimultaneousOps = cfi_query_u8(bank, 0, cfi_info->pri_addr + 10);
-	pri_ext->BurstMode       = cfi_query_u8(bank, 0, cfi_info->pri_addr + 11);
-	pri_ext->PageMode        = cfi_query_u8(bank, 0, cfi_info->pri_addr + 12);
-	pri_ext->VppMin          = cfi_query_u8(bank, 0, cfi_info->pri_addr + 13);
-	pri_ext->VppMax          = cfi_query_u8(bank, 0, cfi_info->pri_addr + 14);
-	pri_ext->TopBottom       = cfi_query_u8(bank, 0, cfi_info->pri_addr + 15);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 5, &pri_ext->SiliconRevision);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 6, &pri_ext->EraseSuspend);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 7, &pri_ext->BlkProt);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 8, &pri_ext->TmpBlkUnprotect);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 9, &pri_ext->BlkProtUnprot);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 10, &pri_ext->SimultaneousOps);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 11, &pri_ext->BurstMode);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 12, &pri_ext->PageMode);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 13, &pri_ext->VppMin);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 14, &pri_ext->VppMax);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 15, &pri_ext->TopBottom);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("Silicon Revision: 0x%x, Erase Suspend: 0x%x, Block protect: 0x%x", pri_ext->SiliconRevision,
 	      pri_ext->EraseSuspend, pri_ext->BlkProt);
@@ -515,9 +629,15 @@ static int cfi_read_atmel_pri_ext(struct flash_bank *bank)
 
 	cfi_info->pri_ext = pri_ext;
 
-	atmel_pri_ext.pri[0] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0);
-	atmel_pri_ext.pri[1] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 1);
-	atmel_pri_ext.pri[2] = cfi_query_u8(bank, 0, cfi_info->pri_addr + 2);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 0, &atmel_pri_ext.pri[0]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 1, &atmel_pri_ext.pri[1]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 2, &atmel_pri_ext.pri[2]);
+	if (retval != ERROR_OK)
+		return retval;
 
 	if ((atmel_pri_ext.pri[0] != 'P') || (atmel_pri_ext.pri[1] != 'R') || (atmel_pri_ext.pri[2] != 'I'))
 	{
@@ -533,18 +653,30 @@ static int cfi_read_atmel_pri_ext(struct flash_bank *bank)
 	pri_ext->pri[1] = atmel_pri_ext.pri[1];
 	pri_ext->pri[2] = atmel_pri_ext.pri[2];
 
-	atmel_pri_ext.major_version = cfi_query_u8(bank, 0, cfi_info->pri_addr + 3);
-	atmel_pri_ext.minor_version = cfi_query_u8(bank, 0, cfi_info->pri_addr + 4);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 3, &atmel_pri_ext.major_version);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 4, &atmel_pri_ext.minor_version);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("pri: '%c%c%c', version: %c.%c", atmel_pri_ext.pri[0], atmel_pri_ext.pri[1], atmel_pri_ext.pri[2], atmel_pri_ext.major_version, atmel_pri_ext.minor_version);
 
 	pri_ext->major_version = atmel_pri_ext.major_version;
 	pri_ext->minor_version = atmel_pri_ext.minor_version;
 
-	atmel_pri_ext.features = cfi_query_u8(bank, 0, cfi_info->pri_addr + 5);
-	atmel_pri_ext.bottom_boot = cfi_query_u8(bank, 0, cfi_info->pri_addr + 6);
-	atmel_pri_ext.burst_mode = cfi_query_u8(bank, 0, cfi_info->pri_addr + 7);
-	atmel_pri_ext.page_mode = cfi_query_u8(bank, 0, cfi_info->pri_addr + 8);
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 5, &atmel_pri_ext.features);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 6, &atmel_pri_ext.bottom_boot);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 7, &atmel_pri_ext.burst_mode);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, cfi_info->pri_addr + 8, &atmel_pri_ext.page_mode);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("features: 0x%2.2x, bottom_boot: 0x%2.2x, burst_mode: 0x%2.2x, page_mode: 0x%2.2x",
 		atmel_pri_ext.features, atmel_pri_ext.bottom_boot, atmel_pri_ext.burst_mode, atmel_pri_ext.page_mode);
@@ -697,7 +829,7 @@ FLASH_BANK_COMMAND_HANDLER(cfi_flash_bank_command)
 	cfi_info->write_algorithm = NULL;
 
 	/* bank wasn't probed yet */
-	cfi_info->qry[0] = -1;
+	cfi_info->qry[0] = 0xff;
 
 	return ERROR_OK;
 }
@@ -722,7 +854,12 @@ static int cfi_intel_erase(struct flash_bank *bank, int first, int last)
 			return retval;
 		}
 
-		if (cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->block_erase_timeout_typ)) == 0x80)
+		uint8_t status;
+		retval = cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->block_erase_timeout_typ), &status);
+		if (retval != ERROR_OK)
+			return retval;
+
+		if (status == 0x80)
 			bank->sectors[i].is_erased = 1;
 		else
 		{
@@ -873,7 +1010,10 @@ static int cfi_intel_protect(struct flash_bank *bank, int set, int first, int la
 		if (!(pri_ext->feature_support & 0x20))
 		{
 			/* Clear lock bits operation may take up to 1.4s */
-			cfi_intel_wait_status_busy(bank, 1400);
+			uint8_t status;
+			retval = cfi_intel_wait_status_busy(bank, 1400, &status);
+			if (retval != ERROR_OK)
+				return retval;
 		}
 		else
 		{
@@ -883,7 +1023,9 @@ static int cfi_intel_protect(struct flash_bank *bank, int set, int first, int la
 			{
 				return retval;
 			}
-			block_status = cfi_get_u8(bank, i, 0x2);
+			retval = cfi_get_u8(bank, i, 0x2, &block_status);
+			if (retval != ERROR_OK)
+				return retval;
 
 			if ((block_status & 0x1) != set)
 			{
@@ -892,7 +1034,10 @@ static int cfi_intel_protect(struct flash_bank *bank, int set, int first, int la
 				{
 					return retval;
 				}
-				cfi_intel_wait_status_busy(bank, 10);
+				uint8_t status;
+				retval = cfi_intel_wait_status_busy(bank, 10, &status);
+				if (retval != ERROR_OK)
+					return retval;
 
 				if (retry > 10)
 					return ERROR_FLASH_OPERATION_FAILED;
@@ -937,7 +1082,10 @@ static int cfi_intel_protect(struct flash_bank *bank, int set, int first, int la
 					return retval;
 				}
 
-				cfi_intel_wait_status_busy(bank, 100);
+				uint8_t status;
+				retval = cfi_intel_wait_status_busy(bank, 100, &status);
+				if (retval != ERROR_OK)
+					return retval;
 			}
 		}
 	}
@@ -1223,7 +1371,8 @@ static int cfi_intel_write_block(struct flash_bank *bank, uint8_t *buffer, uint3
 		if (wsm_error)
 		{
 			/* read status register (outputs debug inforation) */
-			cfi_intel_wait_status_busy(bank, 100);
+			uint8_t status;
+			cfi_intel_wait_status_busy(bank, 100, &status);
 			cfi_intel_clear_status_register(bank);
 			retval = ERROR_FLASH_OPERATION_FAILED;
 			goto cleanup;
@@ -1268,8 +1417,7 @@ static int cfi_spansion_write_block(struct flash_bank *bank, uint8_t *buffer, ui
 	struct working_area *source;
 	uint32_t buffer_size = 32768;
 	uint32_t status;
-	int retval, retvaltemp;
-	int exit_code = ERROR_OK;
+	int retval = ERROR_OK;
 
 	/* input parameters - */
 	/*	R0 = source address */
@@ -1515,7 +1663,11 @@ static int cfi_spansion_write_block(struct flash_bank *bank, uint8_t *buffer, ui
 	{
 		uint32_t thisrun_count = (count > buffer_size) ? buffer_size : count;
 
-		retvaltemp = target_write_buffer(target, source->address, thisrun_count, buffer);
+		retval = target_write_buffer(target, source->address, thisrun_count, buffer);
+		if (retval != ERROR_OK)
+		{
+			break;
+		}
 
 		buf_set_u32(reg_params[0].value, 0, 32, source->address);
 		buf_set_u32(reg_params[1].value, 0, 32, address);
@@ -1531,13 +1683,16 @@ static int cfi_spansion_write_block(struct flash_bank *bank, uint8_t *buffer, ui
 						     cfi_info->write_algorithm->address,
 						     cfi_info->write_algorithm->address + ((target_code_size) - 4),
 						     10000, &armv4_5_info);
+		if (retval != ERROR_OK)
+		{
+			break;
+		}
 
 		status = buf_get_u32(reg_params[5].value, 0, 32);
-
-		if ((retval != ERROR_OK) || (retvaltemp != ERROR_OK) || status != 0x80)
+		if (status != 0x80)
 		{
-			LOG_DEBUG("status: 0x%" PRIx32 , status);
-			exit_code = ERROR_FLASH_OPERATION_FAILED;
+			LOG_ERROR("flash write block failed status: 0x%" PRIx32 , status);
+			retval = ERROR_FLASH_OPERATION_FAILED;
 			break;
 		}
 
@@ -1559,7 +1714,7 @@ static int cfi_spansion_write_block(struct flash_bank *bank, uint8_t *buffer, ui
 	destroy_reg_param(&reg_params[8]);
 	destroy_reg_param(&reg_params[9]);
 
-	return exit_code;
+	return retval;
 }
 
 static int cfi_intel_write_word(struct flash_bank *bank, uint8_t *word, uint32_t address)
@@ -1579,7 +1734,9 @@ static int cfi_intel_write_word(struct flash_bank *bank, uint8_t *word, uint32_t
 		return retval;
 	}
 
-	if (cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->word_write_timeout_max)) != 0x80)
+	uint8_t status;
+	retval = cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->word_write_timeout_max), &status);
+	if (retval != 0x80)
 	{
 		if ((retval = cfi_send_command(bank, 0xff, flash_address(bank, 0, 0x0))) != ERROR_OK)
 		{
@@ -1629,7 +1786,11 @@ static int cfi_intel_write_words(struct flash_bank *bank, uint8_t *word, uint32_
 	{
 		return retval;
 	}
-	if (cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->buf_write_timeout_max)) != 0x80)
+	uint8_t status;
+	retval = cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->buf_write_timeout_max), &status);
+	if (retval != ERROR_OK)
+		return retval;
+	if (status != 0x80)
 	{
 		if ((retval = cfi_send_command(bank, 0xff, flash_address(bank, 0, 0x0))) != ERROR_OK)
 		{
@@ -1656,7 +1817,12 @@ static int cfi_intel_write_words(struct flash_bank *bank, uint8_t *word, uint32_
 	{
 		return retval;
 	}
-	if (cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->buf_write_timeout_max)) != 0x80)
+
+	retval = cfi_intel_wait_status_busy(bank, 1000 * (1 << cfi_info->buf_write_timeout_max), &status);
+	if (retval != ERROR_OK)
+		return retval;
+
+	if (status != 0x80)
 	{
 		if ((retval = cfi_send_command(bank, 0xff, flash_address(bank, 0, 0x0))) != ERROR_OK)
 		{
@@ -2098,9 +2264,15 @@ static int cfi_query_string(struct flash_bank *bank, int address)
 		return retval;
 	}
 
-	cfi_info->qry[0] = cfi_query_u8(bank, 0, 0x10);
-	cfi_info->qry[1] = cfi_query_u8(bank, 0, 0x11);
-	cfi_info->qry[2] = cfi_query_u8(bank, 0, 0x12);
+	retval = cfi_query_u8(bank, 0, 0x10, &cfi_info->qry[0]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, 0x11, &cfi_info->qry[1]);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = cfi_query_u8(bank, 0, 0x12, &cfi_info->qry[2]);
+	if (retval != ERROR_OK)
+		return retval;
 
 	LOG_DEBUG("CFI qry returned: 0x%2.2x 0x%2.2x 0x%2.2x", cfi_info->qry[0], cfi_info->qry[1], cfi_info->qry[2]);
 
@@ -2236,25 +2408,57 @@ static int cfi_probe(struct flash_bank *bank)
 		if (retval != ERROR_OK)
 			return retval;
 
-		cfi_info->pri_id = cfi_query_u16(bank, 0, 0x13);
-		cfi_info->pri_addr = cfi_query_u16(bank, 0, 0x15);
-		cfi_info->alt_id = cfi_query_u16(bank, 0, 0x17);
-		cfi_info->alt_addr = cfi_query_u16(bank, 0, 0x19);
+		retval = cfi_query_u16(bank, 0, 0x13, &cfi_info->pri_id);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u16(bank, 0, 0x15, &cfi_info->pri_addr);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u16(bank, 0, 0x17, &cfi_info->alt_id);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u16(bank, 0, 0x19, &cfi_info->alt_addr);
+		if (retval != ERROR_OK)
+			return retval;
 
 		LOG_DEBUG("qry: '%c%c%c', pri_id: 0x%4.4x, pri_addr: 0x%4.4x, alt_id: 0x%4.4x, alt_addr: 0x%4.4x", cfi_info->qry[0], cfi_info->qry[1], cfi_info->qry[2], cfi_info->pri_id, cfi_info->pri_addr, cfi_info->alt_id, cfi_info->alt_addr);
 
-		cfi_info->vcc_min = cfi_query_u8(bank, 0, 0x1b);
-		cfi_info->vcc_max = cfi_query_u8(bank, 0, 0x1c);
-		cfi_info->vpp_min = cfi_query_u8(bank, 0, 0x1d);
-		cfi_info->vpp_max = cfi_query_u8(bank, 0, 0x1e);
-		cfi_info->word_write_timeout_typ = cfi_query_u8(bank, 0, 0x1f);
-		cfi_info->buf_write_timeout_typ = cfi_query_u8(bank, 0, 0x20);
-		cfi_info->block_erase_timeout_typ = cfi_query_u8(bank, 0, 0x21);
-		cfi_info->chip_erase_timeout_typ = cfi_query_u8(bank, 0, 0x22);
-		cfi_info->word_write_timeout_max = cfi_query_u8(bank, 0, 0x23);
-		cfi_info->buf_write_timeout_max = cfi_query_u8(bank, 0, 0x24);
-		cfi_info->block_erase_timeout_max = cfi_query_u8(bank, 0, 0x25);
-		cfi_info->chip_erase_timeout_max = cfi_query_u8(bank, 0, 0x26);
+		retval = cfi_query_u8(bank, 0, 0x1b, &cfi_info->vcc_min);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x1c, &cfi_info->vcc_max);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x1d, &cfi_info->vpp_min);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x1e, &cfi_info->vpp_max);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x1f, &cfi_info->word_write_timeout_typ);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x20, &cfi_info->buf_write_timeout_typ);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x21, &cfi_info->block_erase_timeout_typ);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x22, &cfi_info->chip_erase_timeout_typ);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x23, &cfi_info->word_write_timeout_max);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x24, &cfi_info->buf_write_timeout_max);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x25, &cfi_info->block_erase_timeout_max);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x26, &cfi_info->chip_erase_timeout_max);
+		if (retval != ERROR_OK)
+			return retval;
 
 		LOG_DEBUG("Vcc min: %x.%x, Vcc max: %x.%x, Vpp min: %u.%x, Vpp max: %u.%x",
 			(cfi_info->vcc_min & 0xf0) >> 4, cfi_info->vcc_min & 0x0f,
@@ -2268,10 +2472,21 @@ static int cfi_probe(struct flash_bank *bank)
 			(1 << cfi_info->block_erase_timeout_max) * (1 << cfi_info->block_erase_timeout_typ),
 			(1 << cfi_info->chip_erase_timeout_max) * (1 << cfi_info->chip_erase_timeout_typ));
 
-		cfi_info->dev_size = 1 << cfi_query_u8(bank, 0, 0x27);
-		cfi_info->interface_desc = cfi_query_u16(bank, 0, 0x28);
-		cfi_info->max_buf_write_size = cfi_query_u16(bank, 0, 0x2a);
-		cfi_info->num_erase_regions = cfi_query_u8(bank, 0, 0x2c);
+		uint8_t data;
+		retval = 1 << cfi_query_u8(bank, 0, 0x27, &data);
+		if (retval != ERROR_OK)
+			return retval;
+		cfi_info->dev_size = data;
+
+		retval = cfi_query_u16(bank, 0, 0x28, &cfi_info->interface_desc);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u16(bank, 0, 0x2a, &cfi_info->max_buf_write_size);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = cfi_query_u8(bank, 0, 0x2c, &cfi_info->num_erase_regions);
+		if (retval != ERROR_OK)
+			return retval;
 
 		LOG_DEBUG("size: 0x%" PRIx32 ", interface desc: %i, max buffer write size: %x", cfi_info->dev_size, cfi_info->interface_desc, (1 << cfi_info->max_buf_write_size));
 
@@ -2280,7 +2495,9 @@ static int cfi_probe(struct flash_bank *bank)
 			cfi_info->erase_region_info = malloc(4 * cfi_info->num_erase_regions);
 			for (i = 0; i < cfi_info->num_erase_regions; i++)
 			{
-				cfi_info->erase_region_info[i] = cfi_query_u32(bank, 0, 0x2d + (4 * i));
+				retval = cfi_query_u32(bank, 0, 0x2d + (4 * i), &cfi_info->erase_region_info[i]);
+				if (retval != ERROR_OK)
+					return retval;
 				LOG_DEBUG("erase region[%i]: %" PRIu32 " blocks of size 0x%" PRIx32 "",
 					  i,
 					  (cfi_info->erase_region_info[i] & 0xffff) + 1,
@@ -2417,7 +2634,10 @@ static int cfi_intel_protect_check(struct flash_bank *bank)
 
 	for (i = 0; i < bank->num_sectors; i++)
 	{
-		uint8_t block_status = cfi_get_u8(bank, i, 0x2);
+		uint8_t block_status;
+		retval = cfi_get_u8(bank, i, 0x2, &block_status);
+		if (retval != ERROR_OK)
+			return retval;
 
 		if (block_status & 1)
 			bank->sectors[i].is_protected = 1;
@@ -2452,7 +2672,10 @@ static int cfi_spansion_protect_check(struct flash_bank *bank)
 
 	for (i = 0; i < bank->num_sectors; i++)
 	{
-		uint8_t block_status = cfi_get_u8(bank, i, 0x2);
+		uint8_t block_status;
+		retval = cfi_get_u8(bank, i, 0x2, &block_status);
+		if (retval != ERROR_OK)
+			return retval;
 
 		if (block_status & 1)
 			bank->sectors[i].is_protected = 1;
@@ -2498,7 +2721,7 @@ static int cfi_info(struct flash_bank *bank, char *buf, int buf_size)
 	int printed;
 	struct cfi_flash_bank *cfi_info = bank->driver_priv;
 
-	if (cfi_info->qry[0] == (char)-1)
+	if (cfi_info->qry[0] == 0xff)
 	{
 		printed = snprintf(buf, buf_size, "\ncfi flash bank not probed yet\n");
 		return ERROR_OK;
diff --git a/src/flash/nor/cfi.h b/src/flash/nor/cfi.h
index fa717dc8..e2ff808b 100644
--- a/src/flash/nor/cfi.h
+++ b/src/flash/nor/cfi.h
@@ -35,7 +35,7 @@ struct cfi_flash_bank
 	uint16_t manufacturer;
 	uint16_t device_id;
 
-	char qry[3];
+	uint8_t qry[3];
 
 	/* identification string */
 	uint16_t pri_id;
@@ -76,7 +76,7 @@ struct cfi_flash_bank
  */
 struct cfi_intel_pri_ext
 {
-	char pri[3];
+	uint8_t pri[3];
 	uint8_t major_version;
 	uint8_t minor_version;
 	uint32_t feature_support;