Change in flashrom[master]: opaque: Implement opaque master hookable {read,write}_status callbacks

[Edward O'Callaghan (Code Review)]

Edward O'Callaghan has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/48134 )

Change subject: opaque: Implement opaque master hookable {read,write}_status callbacks
......................................................................

opaque: Implement opaque master hookable {read,write}_status callbacks

This allows for opaque masters to hook their own bespoke
R/W primatives for status register manipulation. This is
a pre-requirement to allow for ichspi to allow for write-protect
support.

BUG=b:174432470
TEST=builds

Change-Id: I6fd8ba151dba2d0deb4b1dd86ba708d4fd3caeb9
Signed-off-by: Edward O'Callaghan 
---
M chipdrivers.h
M flashchips.c
M opaque.c
M programmer.h
M spi25_statusreg.c
5 files changed, 36 insertions(+), 11 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/34/48134/1

diff --git a/chipdrivers.h b/chipdrivers.h
index cf03811..64a1d73 100644
--- a/chipdrivers.h
+++ b/chipdrivers.h
@@ -113,6 +113,8 @@
 int read_opaque(struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len);
 int write_opaque(struct flashctx *flash, const uint8_t *buf, unsigned int start, unsigned int len);
 int erase_opaque(struct flashctx *flash, unsigned int blockaddr, unsigned int blocklen);
+uint8_t read_status_opaque(const struct flashctx *flash);
+int write_status_opaque(const struct flashctx *flash, int status);

/* at45db.c */
 int probe_spi_at45db(struct flashctx *flash);
diff --git a/flashchips.c b/flashchips.c
index c4ba4c6..e7b13a3 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -18930,6 +18930,8 @@
    	},
    	.write		= write_opaque,
    	.read		= read_opaque,
+		.read_status	= read_status_opaque,
+		.write_status	= write_status_opaque,
    },

{
diff --git a/opaque.c b/opaque.c
index 276934f..de89181 100644
--- a/opaque.c
+++ b/opaque.c
@@ -46,6 +46,20 @@
    return flash->mst->opaque.erase(flash, blockaddr, blocklen);
 }

+uint8_t read_status_opaque(const struct flashctx *flash)
+{
+	if (flash->mst->opaque.read_status)
+		return flash->mst->opaque.read_status(flash);
+	return 1;
+}
+
+int write_status_opaque(const struct flashctx *flash, int status)
+{
+	if (flash->mst->opaque.write_status)
+		return flash->mst->opaque.write_status(flash, status);
+	return 1;
+}
+
 int register_opaque_master(const struct opaque_master *mst)
 {
    struct registered_master rmst;
diff --git a/programmer.h b/programmer.h
index c93bf83..888c62c 100644
--- a/programmer.h
+++ b/programmer.h
@@ -722,6 +722,8 @@
    int (*read) (struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len);
    int (*write) (struct flashctx *flash, const uint8_t *buf, unsigned int start, unsigned int len);
    int (*erase) (struct flashctx *flash, unsigned int blockaddr, unsigned int blocklen);
+	uint8_t (*read_status) (const struct flashctx *flash);
+	int (*write_status) (const struct flashctx *flash, int status);
    const void *data;
 };
 int register_opaque_master(const struct opaque_master *mst);
diff --git a/spi25_statusreg.c b/spi25_statusreg.c
index 34f9ad4..a6d8676 100644
--- a/spi25_statusreg.c
+++ b/spi25_statusreg.c
@@ -83,11 +83,15 @@
    		 "EWSR is needed\n");
    	feature_bits |= FEATURE_WRSR_EWSR;
    }
-	if (feature_bits & FEATURE_WRSR_WREN)
-		ret = spi_write_status_register_flag(flash, status, JEDEC_WREN);
-	if (ret && (feature_bits & FEATURE_WRSR_EWSR))
-		ret = spi_write_status_register_flag(flash, status, JEDEC_EWSR);
-	return ret;
+	if (flash->chip->write_status) {
+                ret = flash->chip->write_status(flash, status);
+        } else {
+                if (feature_bits & FEATURE_WRSR_WREN)
+                        ret = spi_write_status_register_flag(flash, status, JEDEC_WREN);
+                if (ret && (feature_bits & FEATURE_WRSR_EWSR))
+                        ret = spi_write_status_register_flag(flash, status, JEDEC_EWSR);
+        }
+        return ret;
 }

uint8_t spi_read_status_register(const struct flashctx *flash)
@@ -95,16 +99,17 @@
    static const unsigned char cmd[JEDEC_RDSR_OUTSIZE] = { JEDEC_RDSR };
    /* FIXME: No workarounds for driver/hardware bugs in generic code. */
    unsigned char readarr[2]; /* JEDEC_RDSR_INSIZE=1 but wbsio needs 2 */
-	int ret;
+	int ret = 0;

/* Read Status Register */
-	ret = spi_send_command(flash, sizeof(cmd), sizeof(readarr), cmd, readarr);
-	if (ret) {
+	if (flash->chip->read_status)
+		readarr[0] = flash->chip->read_status(flash);
+	else
+		ret = spi_send_command(flash, sizeof(cmd), sizeof(readarr), cmd, readarr);
+	if (ret)
    	msg_cerr("RDSR failed!\n");
-		/* FIXME: We should propagate the error. */
-		return 0;
-	}

+	/* FIXME: We should propagate the error. */
    return readarr[0];
 }