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: svn://svn.coreboot.org/coreboot/trunk@3971 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

util/flashrom/flash.h

@@ -58,6 +58,36 @@
   #define INL  inl
 #endif
 
+static inline void writeb(uint8_t b, volatile void *addr)
+{
+	*(volatile uint8_t *) addr = b;
+}
+
+static inline void writew(uint16_t b, volatile void *addr)
+{
+	*(volatile uint16_t *) addr = b;
+}
+
+static inline void writel(uint32_t b, volatile void *addr)
+{
+	*(volatile uint32_t *) addr = b;
+}
+
+static inline uint8_t readb(const volatile void *addr)
+{
+	return *(volatile uint8_t *) addr;
+}
+
+static inline uint16_t readw(const volatile void *addr)
+{
+	return *(volatile uint16_t *) addr;
+}
+
+static inline uint32_t readl(const volatile void *addr)
+{
+	return *(volatile uint32_t *) addr;
+}
+
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
 
 struct flashchip {