[coreboot-gerrit] [M] Change in coreboot[main]: spi/winbond: Use spi_flash_bpbits in winbond_bpbits_to_region

[Felix Held (Code Review)]

Felix Held has submitted this change. ( https://review.coreboot.org/c/coreboot/+/42113?usp=email )

Change subject: spi/winbond: Use spi_flash_bpbits in winbond_bpbits_to_region
......................................................................

spi/winbond: Use spi_flash_bpbits in winbond_bpbits_to_region

This consolidates the bp, tb, cmp, srp0 and srp1 variables under the new
spi_flash_bpbits struct to allow treating them as one unit in the
refactoring to follow.

Change-Id: I2a1a77fb73047df733498c0fa8b8de1153c3b09e
Signed-off-by: Daniel Gröber 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/42113
Reviewed-by: Jakub Czapiga 
Tested-by: build bot (Jenkins) 
---
M src/drivers/spi/winbond.c
1 file changed, 58 insertions(+), 19 deletions(-)

Approvals:
  Jakub Czapiga: Looks good to me, approved
  build bot (Jenkins): Verified

diff --git a/src/drivers/spi/winbond.c b/src/drivers/spi/winbond.c
index 7992629..3137bfe 100644
--- a/src/drivers/spi/winbond.c
+++ b/src/drivers/spi/winbond.c
@@ -19,14 +19,14 @@
    	uint8_t tb   : 1;
    	uint8_t sec  : 1;
    	uint8_t srp0 : 1;
-	} bp3;
+	} bp3; /* for example: W25Q128FW */
    struct {
    	uint8_t busy : 1;
    	uint8_t wel  : 1;
    	uint8_t bp   : 4;
    	uint8_t tb   : 1;
    	uint8_t srp0 : 1;
-	} bp4;
+	} bp4; /* for example: W25Q256J */
 };

union status_reg2 {
@@ -254,16 +254,15 @@
  * SEC (if available) must be zero.
  */
 static void winbond_bpbits_to_region(const size_t granularity,
-				     const u8 bp,
-				     bool tb,
-				     const bool cmp,
+				     const struct spi_flash_bpbits *bits,
    			     const size_t flash_size,
    			     struct region *out)
 {
    size_t protected_size =
-		MIN(bp ? granularity << (bp - 1) : 0, flash_size);
+		MIN(bits->bp ? granularity << (bits->bp - 1) : 0, flash_size);

-	if (cmp) {
+	int tb = bits->tb;
+	if (bits->cmp) {
    	protected_size = flash_size - protected_size;
    	tb = !tb;
    }
@@ -287,8 +286,7 @@
 {
    const struct spi_flash_part_id *params;
    struct region wp_region;
-	union status_reg2 reg2;
-	u8 bp, tb;
+	struct spi_flash_bpbits bpbits;
    int ret;

params = flash->part;
@@ -299,34 +297,75 @@
    const size_t granularity = (1 << params->protection_granularity_shift);

union status_reg1 reg1 = { .u = 0 };
+	union status_reg2 reg2 = { .u = 0 };

ret = spi_flash_cmd(&flash->spi, flash->status_cmd, &reg1.u,
    		    sizeof(reg1.u));
    if (ret)
    	return ret;

+	ret = spi_flash_cmd(&flash->spi, CMD_W25_RDSR2, &reg2.u,
+			    sizeof(reg2.u));
+	if (ret)
+		return ret;
+
    if (params->bp_bits == 3) {
    	if (reg1.bp3.sec) {
    		// FIXME: not supported
    		return -1;
    	}

-		bp = reg1.bp3.bp;
-		tb = reg1.bp3.tb;
+		bpbits = (struct spi_flash_bpbits){
+			.bp = reg1.bp3.bp,
+			.cmp = reg2.cmp,
+			.tb = reg1.bp3.tb,
+			/*
+			 * For W25Q*{,F}* parts:
+			 *  srp1 srp0
+			 *   0    0  | writable if WEL==1
+			 *   0    1  | writable if WEL==1 && #WP==Vcc
+			 *   1    0  | not writable until next power-down
+			 *   1    1  | not writable, permanently
+			 *
+			 * checked datasheets: W25Q128FV, (W25Q80, W25Q16,
+			 *   W25Q32)
+			 */
+			.winbond = {
+				.srp0 = reg1.bp3.srp0,
+				.srp1 = reg2.srp1,
+			},
+		};
    } else if (params->bp_bits == 4) {
-		bp = reg1.bp4.bp;
-		tb = reg1.bp4.tb;
+		bpbits = (struct spi_flash_bpbits){
+			.bp = reg1.bp4.bp,
+			.cmp = reg2.cmp,
+			.tb = reg1.bp4.tb,
+			/*
+			 * For W25Q*{J,D}* parts:
+			 *
+			 *  srp1 srp0
+			 *   0    0  | writable if WEL==1
+			 *   0    1  | writable if WEL==1 && #WP==Vcc
+			 *   1    x  | not writable until next power-down
+			 *
+			 * checked datasheets: W25Q132JW, W25Q128JW, W25Q256JV.
+			 *   W25Q16DW
+			 *
+			 * The srp0/srp1 bits got renamed to srp/srl in the
+			 * datasheets, we retain the prior naming
+			 * convention for the structs though.
+			 */
+			.winbond = {
+				.srp0 = reg1.bp4.srp0,
+				.srp1 = reg2.srp1,
+			},
+		};
    } else {
    	// FIXME: not supported
    	return -1;
    }

-	ret = spi_flash_cmd(&flash->spi, CMD_W25_RDSR2, &reg2.u,
-			    sizeof(reg2.u));
-	if (ret)
-		return ret;
-
-	winbond_bpbits_to_region(granularity, bp, tb, reg2.cmp, flash->size,
+	winbond_bpbits_to_region(granularity, &bpbits, flash->size,
    			 &wp_region);

if (!region_sz(&wp_region)) {