Original v2 revision: 3971

flashrom: Use helper functions to access flash chips.

Right now we perform direct pointer manipulation without any abstraction
to read from and write to memory mapped flash chips. That makes it
impossible to drive any flasher which does not mmap the whole chip.

Using helper functions readb() and writeb() allows a driver for external
flash programmers like Paraflasher to replace readb and writeb with
calls to its own chip access routines.

This patch has the additional advantage of removing lots of unnecessary
casts to volatile uint8_t * and now-superfluous parentheses which caused
poor readability.

I used the semantic patcher Coccinelle to create this patch. The
semantic patch follows:
@@
expression a;
typedef uint8_t;
volatile uint8_t *b;
@@
- *(b) = (a);
+ writeb(a, b);
@@
volatile uint8_t *b;
@@
- *(b)
+ readb(b)
@@
type T;
T b;
@@
(
 readb
|
 writeb
)
 (...,
- (T)
- (b)
+ b
 )

In contrast to a sed script, the semantic patch performs type checking
before converting anything.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: FENG Yu Ning <fengyuning1984@gmail.com>
Tested-by: Joe Julian


git-svn-id: https://code.coreboot.org/svn/flashrom/trunk@418 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

1 files changed, 27 insertions, 27 deletions

diff --git a/82802ab.c b/82802ab.c
index 5e5b1a5..9bbee8d 100644
--- a/82802ab.c
+++ b/82802ab.c
@@ -49,23 +49,23 @@ int probe_82802ab(struct flashchip *flash)
 	uint8_t id1, id2;
 
 #if 0
-	*(volatile uint8_t *)(bios + 0x5555) = 0xAA;
-	*(volatile uint8_t *)(bios + 0x2AAA) = 0x55;
-	*(volatile uint8_t *)(bios + 0x5555) = 0x90;
+	writeb(0xAA, bios + 0x5555);
+	writeb(0x55, bios + 0x2AAA);
+	writeb(0x90, bios + 0x5555);
 #endif
 
-	*bios = 0xff;
+	writeb(0xff, bios);
 	myusec_delay(10);
-	*bios = 0x90;
+	writeb(0x90, bios);
 	myusec_delay(10);
 
-	id1 = *(volatile uint8_t *)bios;
-	id2 = *(volatile uint8_t *)(bios + 0x01);
+	id1 = readb(bios);
+	id2 = readb(bios + 0x01);
 
 	/* Leave ID mode */
-	*(volatile uint8_t *)(bios + 0x5555) = 0xAA;
-	*(volatile uint8_t *)(bios + 0x2AAA) = 0x55;
-	*(volatile uint8_t *)(bios + 0x5555) = 0xF0;
+	writeb(0xAA, bios + 0x5555);
+	writeb(0x55, bios + 0x2AAA);
+	writeb(0xF0, bios + 0x5555);
 
 	myusec_delay(10);
 
@@ -84,25 +84,25 @@ uint8_t wait_82802ab(volatile uint8_t *bios)
 	uint8_t status;
 	uint8_t id1, id2;
 
-	*bios = 0x70;
-	if ((*bios & 0x80) == 0) {	// it's busy
-		while ((*bios & 0x80) == 0) ;
+	writeb(0x70, bios);
+	if ((readb(bios) & 0x80) == 0) {	// it's busy
+		while ((readb(bios) & 0x80) == 0) ;
 	}
 
-	status = *bios;
+	status = readb(bios);
 
 	// put another command to get out of status register mode
 
-	*bios = 0x90;
+	writeb(0x90, bios);
 	myusec_delay(10);
 
-	id1 = *(volatile uint8_t *)bios;
-	id2 = *(volatile uint8_t *)(bios + 0x01);
+	id1 = readb(bios);
+	id2 = readb(bios + 0x01);
 
 	// this is needed to jam it out of "read id" mode
-	*(volatile uint8_t *)(bios + 0x5555) = 0xAA;
-	*(volatile uint8_t *)(bios + 0x2AAA) = 0x55;
-	*(volatile uint8_t *)(bios + 0x5555) = 0xF0;
+	writeb(0xAA, bios + 0x5555);
+	writeb(0x55, bios + 0x2AAA);
+	writeb(0xF0, bios + 0x5555);
 
 	return status;
 }
@@ -115,23 +115,23 @@ int erase_82802ab_block(struct flashchip *flash, int offset)
 	uint8_t status;
 
 	// clear status register
-	*bios = 0x50;
+	writeb(0x50, bios);
 	//printf("Erase at %p\n", bios);
 	// clear write protect
 	//printf("write protect is at %p\n", (wrprotect));
 	//printf("write protect is 0x%x\n", *(wrprotect));
-	*(wrprotect) = 0;
+	writeb(0, wrprotect);
 	//printf("write protect is 0x%x\n", *(wrprotect));
 
 	// now start it
-	*(volatile uint8_t *)(bios) = 0x20;
-	*(volatile uint8_t *)(bios) = 0xd0;
+	writeb(0x20, bios);
+	writeb(0xd0, bios);
 	myusec_delay(10);
 	// now let's see what the register is
 	status = wait_82802ab(flash->virtual_memory);
 	//print_82802ab_status(status);
 	for (j = 0; j < flash->page_size; j++) {
-		if (*(bios + j) != 0xFF) {
+		if (readb(bios + j) != 0xFF) {
 			printf("BLOCK ERASE failed at 0x%x\n", offset);
 			return -1;
 		}
@@ -162,8 +162,8 @@ void write_page_82802ab(volatile uint8_t *bios, uint8_t *src,
 
 	for (i = 0; i < page_size; i++) {
 		/* transfer data from source to destination */
-		*dst = 0x40;
-		*dst++ = *src++;
+		writeb(0x40, dst);
+		writeb(*src++, dst++);
 		wait_82802ab(bios);
 	}
 }