driver/mxc_i2c: Move static data structure to global_data

This driver needs a data structure in SRAM before SDRAM is available.
This is not alway the case using .data section. Moving this data
structure to global_data guarantees it is writable.

Signed-off-by: York Sun <yorksun@freescale.com>
CC: Troy Kisky <troy.kisky@boundarydevices.com>

drivers/i2c/mxc_i2c.c

@@ -22,6 +22,8 @@
 #include <i2c.h>
 #include <watchdog.h>
 
+DECLARE_GLOBAL_DATA_PTR;
+
 #ifdef I2C_QUIRK_REG
 struct mxc_i2c_regs {
 	uint8_t		iadr;
@@ -411,12 +413,6 @@ struct sram_data {
 	struct i2c_parms i2c_data[3];
 };
 
-/*
- * For SPL boot some boards need i2c before SDRAM is initialized so force
- * variables to live in SRAM
- */
-static struct sram_data __attribute__((section(".data"))) srdata;
-
 static void * const i2c_bases[] = {
 #if defined(CONFIG_MX25)
 	(void *)IMX_I2C_BASE,
@@ -445,9 +441,10 @@ void *i2c_get_base(struct i2c_adapter *adap)
 
 static struct i2c_parms *i2c_get_parms(void *base)
 {
+	struct sram_data *srdata = (void *)gd->srdata;
 	int i = 0;
-	struct i2c_parms *p = srdata.i2c_data;
-	while (i < ARRAY_SIZE(srdata.i2c_data)) {
+	struct i2c_parms *p = srdata->i2c_data;
+	while (i < ARRAY_SIZE(srdata->i2c_data)) {
 		if (p->base == base)
 			return p;
 		p++;
@@ -490,8 +487,9 @@ static int mxc_i2c_probe(struct i2c_adapter *adap, uint8_t chip)
 void bus_i2c_init(void *base, int speed, int unused,
 		int (*idle_bus_fn)(void *p), void *idle_bus_data)
 {
+	struct sram_data *srdata = (void *)gd->srdata;
 	int i = 0;
-	struct i2c_parms *p = srdata.i2c_data;
+	struct i2c_parms *p = srdata->i2c_data;
 	if (!base)
 		return;
 	for (;;) {
@@ -505,7 +503,7 @@ void bus_i2c_init(void *base, int speed, int unused,
 		}
 		p++;
 		i++;
-		if (i >= ARRAY_SIZE(srdata.i2c_data))
+		if (i >= ARRAY_SIZE(srdata->i2c_data))
 			return;
 	}
 	bus_i2c_set_bus_speed(base, speed);

include/asm-generic/global_data.h

@@ -80,6 +80,9 @@ typedef struct global_data {
 #if defined(CONFIG_SYS_I2C)
 	int		cur_i2c_bus;	/* current used i2c bus */
 #endif
+#ifdef CONFIG_SYS_I2C_MXC
+	void *srdata[10];
+#endif
 	unsigned long timebase_h;
 	unsigned long timebase_l;
 	struct arch_global_data arch;	/* architecture-specific data */