MIPS: BCM47XX: Make ssb init NVRAM instead of bcm47xx polling it

This makes NVRAM code less bcm47xx/ssb specific allowing it to become a
standalone driver in the future. A similar patch for bcma will follow
when it's ready.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7612/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/bcm47xx/nvram.c

@@ -98,7 +98,14 @@ found:
 	return 0;
 }
 
-static int bcm47xx_nvram_init_from_mem(u32 base, u32 lim)
+/*
+ * On bcm47xx we need access to the NVRAM very early, so we can't use mtd
+ * subsystem to access flash. We can't even use platform device / driver to
+ * store memory offset.
+ * To handle this we provide following symbol. It's supposed to be called as
+ * soon as we get info about flash device, before any NVRAM entry is needed.
+ */
+int bcm47xx_nvram_init_from_mem(u32 base, u32 lim)
 {
 	void __iomem *iobase;
 	int err;
@@ -114,25 +121,6 @@ static int bcm47xx_nvram_init_from_mem(u32 base, u32 lim)
 	return err;
 }
 
-#ifdef CONFIG_BCM47XX_SSB
-static int nvram_init_ssb(void)
-{
-	struct ssb_mipscore *mcore = &bcm47xx_bus.ssb.mipscore;
-	u32 base;
-	u32 lim;
-
-	if (mcore->pflash.present) {
-		base = mcore->pflash.window;
-		lim = mcore->pflash.window_size;
-	} else {
-		pr_err("Couldn't find supported flash memory\n");
-		return -ENXIO;
-	}
-
-	return bcm47xx_nvram_init_from_mem(base, lim);
-}
-#endif
-
 #ifdef CONFIG_BCM47XX_BCMA
 static int nvram_init_bcma(void)
 {
@@ -168,7 +156,7 @@ static int nvram_init(void)
 	switch (bcm47xx_bus_type) {
 #ifdef CONFIG_BCM47XX_SSB
 	case BCM47XX_BUS_TYPE_SSB:
-		return nvram_init_ssb();
+		break;
 #endif
 #ifdef CONFIG_BCM47XX_BCMA
 	case BCM47XX_BUS_TYPE_BCMA:

arch/mips/include/asm/mach-bcm47xx/bcm47xx_nvram.h

@@ -32,6 +32,7 @@ struct nvram_header {
 #define NVRAM_MAX_VALUE_LEN 255
 #define NVRAM_MAX_PARAM_LEN 64
 
+int bcm47xx_nvram_init_from_mem(u32 base, u32 lim);
 extern int bcm47xx_nvram_getenv(char *name, char *val, size_t val_len);
 
 static inline void bcm47xx_nvram_parse_macaddr(char *buf, u8 macaddr[6])

drivers/ssb/driver_mipscore.c

@@ -15,6 +15,9 @@
 #include <linux/serial_core.h>
 #include <linux/serial_reg.h>
 #include <linux/time.h>
+#ifdef CONFIG_BCM47XX
+#include <bcm47xx_nvram.h>
+#endif
 
 #include "ssb_private.h"
 
@@ -210,6 +213,7 @@ static void ssb_mips_serial_init(struct ssb_mipscore *mcore)
 static void ssb_mips_flash_detect(struct ssb_mipscore *mcore)
 {
 	struct ssb_bus *bus = mcore->dev->bus;
+	struct ssb_sflash *sflash = &mcore->sflash;
 	struct ssb_pflash *pflash = &mcore->pflash;
 
 	/* When there is no chipcommon on the bus there is 4MB flash */
@@ -242,7 +246,15 @@ static void ssb_mips_flash_detect(struct ssb_mipscore *mcore)
 	}
 
 ssb_pflash:
-	if (pflash->present) {
+	if (sflash->present) {
+#ifdef CONFIG_BCM47XX
+		bcm47xx_nvram_init_from_mem(sflash->window, sflash->size);
+#endif
+	} else if (pflash->present) {
+#ifdef CONFIG_BCM47XX
+		bcm47xx_nvram_init_from_mem(pflash->window, pflash->window_size);
+#endif
+
 		ssb_pflash_data.width = pflash->buswidth;
 		ssb_pflash_resource.start = pflash->window;
 		ssb_pflash_resource.end = pflash->window + pflash->window_size;