[coreboot] [PATCH 2/2] flashrom: cleanups to enable_flash_cs5536 function

[Mart Raudsepp]

Improve error handling and make RCONF_DEFAULT_MSR address be a constant.

Signed-off-by: Mart Raudsepp <mart.raudsepp at artecdesign.ee>
---
 chipset_enable.c |   42 +++++++++++++++++++++++++++++++++++-------
 1 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/chipset_enable.c b/chipset_enable.c
index d6ef92e..f5a6612 100644
--- a/chipset_enable.c
+++ b/chipset_enable.c
@@ -228,11 +228,11 @@ static int enable_flash_cs5530(struct pci_dev *dev, const char *name)
 
 static int enable_flash_cs5536(struct pci_dev *dev, const char *name)
 {
-	#define MSR_NORF_CTL	0x51400018
+	#define MSR_RCONF_DEFAULT	0x1808
+	#define MSR_NORF_CTL		0x51400018
 
 	int fd_msr;
 	unsigned char buf[8];
-	unsigned int addr = 0x1808;
 
 	/* Geode systems write protect the BIOS via RCONFs (cache
 	 * settings similar to MTRRs). To unlock, change MSR 0x1808
@@ -258,41 +258,69 @@ static int enable_flash_cs5536(struct pci_dev *dev, const char *name)
 		perror("open msr");
 		return -1;
 	}
-	lseek64(fd_msr, (off64_t) addr, SEEK_SET);
-	read(fd_msr, buf, 8);
+
+	if (lseek64(fd_msr, (off64_t) MSR_RCONF_DEFAULT, SEEK_SET) == -1) {
+		perror("lseek64");
+		close(fd_msr);
+		return -1;
+	}
+
+	if (read(fd_msr, buf, 8) != 8) {
+		perror("read");
+		close(fd_msr);
+		return -1;
+	}
 
 	printf("Enabling Geode MSR to write to flash.\n");
 
 	if (buf[7] != 0x22) {
 		buf[7] &= 0xFB;
-		lseek64(fd_msr, (off64_t) addr, SEEK_SET);
+		if (lseek64(fd_msr, (off64_t) MSR_RCONF_DEFAULT, SEEK_SET) == -1) {
+			perror("lseek64");
+			close(fd_msr);
+			return -1;
+		}
+
 		if (write(fd_msr, buf, 8) < 0) {
 			perror("msr write");
 			printf
 			    ("Cannot write to MSR.  Make sure the msr kernel module is loaded: 'modprobe msr'\n");
+			close(fd_msr);
 			return -1;
 		}
 	}
 
-	lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET);
+	if (lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET) == -1) {
+		perror("lseek64");
+		close(fd_msr);
+		return -1;
+	}
+
 	if (read(fd_msr, buf, 8) != 8) {
 		perror("read msr");
+		close(fd_msr);
 		return -1;
 	}
 
 	/* Raise WE_CS3 bit */
 	buf[0] |= 0x08;
 
-	lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET);
+	if (lseek64(fd_msr, (off64_t) MSR_NORF_CTL, SEEK_SET) == -1) {
+		perror("lseek64");
+		close(fd_msr);
+		return -1;
+	}
 	if (write(fd_msr, buf, 8) < 0) {
 		perror("msr write");
 		printf
 		    ("Cannot write to MSR.  Make sure the msr kernel module is loaded: 'modprobe msr'\n");
+		close(fd_msr);
 		return -1;
 	}
 
 	close(fd_msr);
 
+	#undef MSR_RCONF_DEFAULT
 	#undef MSR_NORF_CTL
 	return 0;
 }
-- 
1.5.4