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.

Tested-by: Joe Julian

Corresponding to flashrom svn r418 and coreboot v2 svn r3971.

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

1 files changed, 16 insertions, 16 deletions

diff --git a/m29f002.c b/m29f002.c
index 8afef79..f806a2d 100644
--- a/m29f002.c
+++ b/m29f002.c
@@ -22,12 +22,12 @@
 
 int erase_m29f002(struct flashchip *flash) {
 	volatile uint8_t *bios = flash->virtual_memory;
-	*(volatile uint8_t *)(bios + 0x555) = 0xaa;
-	*(volatile uint8_t *)(bios + 0xaaa) = 0x55;
-	*(volatile uint8_t *)(bios + 0x555) = 0x80;
-	*(volatile uint8_t *)(bios + 0x555) = 0xaa;
-	*(volatile uint8_t *)(bios + 0xaaa) = 0x55;
-	*(volatile uint8_t *)(bios + 0x555) = 0x10;
+	writeb(0xaa, bios + 0x555);
+	writeb(0x55, bios + 0xaaa);
+	writeb(0x80, bios + 0x555);
+	writeb(0xaa, bios + 0x555);
+	writeb(0x55, bios + 0xaaa);
+	writeb(0x10, bios + 0x555);
 	myusec_delay(10);
 	toggle_ready_jedec(bios);
 	return 0;
@@ -35,21 +35,21 @@ int erase_m29f002(struct flashchip *flash) {
 
 static void rewrite_block(volatile uint8_t *bios, uint8_t *src, volatile uint8_t *dst, int size) {
 	/* erase */
-	*(volatile uint8_t *)(bios + 0x555) = 0xaa;
-	*(volatile uint8_t *)(bios + 0xaaa) = 0x55;
-	*(volatile uint8_t *)(bios + 0x555) = 0x80;
-	*(volatile uint8_t *)(bios + 0x555) = 0xaa;
-	*(volatile uint8_t *)(bios + 0xaaa) = 0x55;
-	*dst = 0x30;
+	writeb(0xaa, bios + 0x555);
+	writeb(0x55, bios + 0xaaa);
+	writeb(0x80, bios + 0x555);
+	writeb(0xaa, bios + 0x555);
+	writeb(0x55, bios + 0xaaa);
+	writeb(0x30, dst);
 	myusec_delay(10);
 	toggle_ready_jedec(bios);
 
 	/* program */
 	while (size--) {
-		*(volatile uint8_t *)(bios + 0x555) = 0xaa;
-		*(volatile uint8_t *)(bios + 0xaaa) = 0x55;
-		*(volatile uint8_t *)(bios + 0x555) = 0xa0;
-		*dst = *src;
+		writeb(0xaa, bios + 0x555);
+		writeb(0x55, bios + 0xaaa);
+		writeb(0xa0, bios + 0x555);
+		writeb(*src, dst);
 		toggle_ready_jedec(dst);
 		dst++;
 		src++;