Enable spi_flash_read to read > SPI_FLASH_MAX_READ_SIZE

BUG=chromium:542789
BRANCH=none
TEST=make buildall

Change-Id: I55bf5bdb09b10be1c522ea4d843690abcc45abb2
Reviewed-on: https://chromium-review.googlesource.com/391867
Commit-Ready: Philip Chen <philipchen@chromium.org>
Tested-by: Philip Chen <philipchen@chromium.org>
Reviewed-by: Aseda Aboagye <aaboagye@chromium.org>

2 files changed, 22 insertions, 24 deletions

diff --git a/chip/mec1322/flash.c b/chip/mec1322/flash.c
index e1cbc3c589..1564b93b48 100644
--- a/chip/mec1322/flash.c
+++ b/chip/mec1322/flash.c
@@ -36,21 +36,7 @@ struct flash_wp_state {
  */
 int flash_physical_read(int offset, int size, char *data)
 {
-	int ret = EC_SUCCESS;
-	int i, read_size;
-
-	for (i = 0; i < size; i += read_size) {
-		read_size = MIN((size - i), SPI_FLASH_MAX_READ_SIZE);
-		ret = spi_flash_read((uint8_t *)(data + i),
-					offset + i,
-					read_size);
-		if (ret != EC_SUCCESS)
-			break;
-		/* yield so other tasks get a chance to wake up */
-		msleep(1);
-	}
-
-	return ret;
+	return spi_flash_read(data, offset, size);
 }
 
 /**
diff --git a/common/spi_flash.c b/common/spi_flash.c
index c49215a3f4..b9ba3538ac 100644
--- a/common/spi_flash.c
+++ b/common/spi_flash.c
@@ -143,23 +143,35 @@ int spi_flash_set_status(int reg1, int reg2)
 /**
  * Returns the content of SPI flash
  *
- * @param buf Buffer to write flash contents
+ * @param buf_usr Buffer to write flash contents
  * @param offset Flash offset to start reading from
- * @param bytes Number of bytes to read. Limited by receive buffer to 256.
+ * @param bytes Number of bytes to read.
  *
  * @return EC_SUCCESS, or non-zero if any error.
  */
 int spi_flash_read(uint8_t *buf_usr, unsigned int offset, unsigned int bytes)
 {
-	uint8_t cmd[4] = {SPI_FLASH_READ,
-			  (offset >> 16) & 0xFF,
-			  (offset >> 8) & 0xFF,
-			  offset & 0xFF};
-
+	int i, read_size, ret;
+	uint8_t cmd[4];
 	if (offset + bytes > CONFIG_FLASH_SIZE)
 		return EC_ERROR_INVAL;
-
-	return spi_transaction(SPI_FLASH_DEVICE, cmd, 4, buf_usr, bytes);
+	cmd[0] = SPI_FLASH_READ;
+	for (i = 0; i < bytes; i += read_size) {
+		offset += i;
+		cmd[1] = (offset >> 16) & 0xFF;
+		cmd[2] = (offset >> 8) & 0xFF;
+		cmd[3] = offset & 0xFF;
+		read_size = MIN((bytes - i), SPI_FLASH_MAX_READ_SIZE);
+		ret = spi_transaction(SPI_FLASH_DEVICE,
+			cmd,
+			4,
+			buf_usr + i,
+			read_size);
+		if (ret != EC_SUCCESS)
+			break;
+		msleep(1);
+	}
+	return ret;
 }
 
 /**