bcma: detect and register serial flash device

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/bcma/Kconfig

@@ -48,7 +48,7 @@ config BCMA_DRIVER_MIPS
 
 config BCMA_SFLASH
 	bool
-	depends on BCMA_DRIVER_MIPS && BROKEN
+	depends on BCMA_DRIVER_MIPS
 	default y
 
 config BCMA_NFLASH

drivers/bcma/bcma_private.h

@@ -54,6 +54,7 @@ u32 bcma_pmu_get_clockcpu(struct bcma_drv_cc *cc);
 #ifdef CONFIG_BCMA_SFLASH
 /* driver_chipcommon_sflash.c */
 int bcma_sflash_init(struct bcma_drv_cc *cc);
+extern struct platform_device bcma_sflash_dev;
 #else
 static inline int bcma_sflash_init(struct bcma_drv_cc *cc)
 {

drivers/bcma/driver_chipcommon_sflash.c

@@ -5,15 +5,132 @@
  * Licensed under the GNU/GPL. See COPYING for details.
  */
 
+#include <linux/platform_device.h>
 #include <linux/bcma/bcma.h>
-#include <linux/bcma/bcma_driver_chipcommon.h>
-#include <linux/delay.h>
 
 #include "bcma_private.h"
 
+static struct resource bcma_sflash_resource = {
+	.name	= "bcma_sflash",
+	.start	= BCMA_SFLASH,
+	.end	= 0,
+	.flags  = IORESOURCE_MEM | IORESOURCE_READONLY,
+};
+
+struct platform_device bcma_sflash_dev = {
+	.name		= "bcma_sflash",
+	.resource	= &bcma_sflash_resource,
+	.num_resources	= 1,
+};
+
+struct bcma_sflash_tbl_e {
+	char *name;
+	u32 id;
+	u32 blocksize;
+	u16 numblocks;
+};
+
+static struct bcma_sflash_tbl_e bcma_sflash_st_tbl[] = {
+	{ "", 0x14, 0x10000, 32, },
+	{ 0 },
+};
+
+static struct bcma_sflash_tbl_e bcma_sflash_sst_tbl[] = {
+	{ 0 },
+};
+
+static struct bcma_sflash_tbl_e bcma_sflash_at_tbl[] = {
+	{ 0 },
+};
+
+static void bcma_sflash_cmd(struct bcma_drv_cc *cc, u32 opcode)
+{
+	int i;
+	bcma_cc_write32(cc, BCMA_CC_FLASHCTL,
+			BCMA_CC_FLASHCTL_START | opcode);
+	for (i = 0; i < 1000; i++) {
+		if (!(bcma_cc_read32(cc, BCMA_CC_FLASHCTL) &
+		      BCMA_CC_FLASHCTL_BUSY))
+			return;
+		cpu_relax();
+	}
+	bcma_err(cc->core->bus, "SFLASH control command failed (timeout)!\n");
+}
+
 /* Initialize serial flash access */
 int bcma_sflash_init(struct bcma_drv_cc *cc)
 {
-	bcma_err(cc->core->bus, "Serial flash support is broken\n");
+	struct bcma_bus *bus = cc->core->bus;
+	struct bcma_sflash *sflash = &cc->sflash;
+	struct bcma_sflash_tbl_e *e;
+	u32 id, id2;
+
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_DP);
+
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, 0);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RES);
+		id = bcma_cc_read32(cc, BCMA_CC_FLASHDATA);
+
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, 1);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RES);
+		id2 = bcma_cc_read32(cc, BCMA_CC_FLASHDATA);
+
+		switch (id) {
+		case 0xbf:
+			for (e = bcma_sflash_sst_tbl; e->name; e++) {
+				if (e->id == id2)
+					break;
+			}
+			break;
+		default:
+			for (e = bcma_sflash_st_tbl; e->name; e++) {
+				if (e->id == id)
+					break;
+			}
+			break;
+		}
+		if (!e->name) {
+			bcma_err(bus, "Unsupported ST serial flash (id: 0x%X, id2: 0x%X)\n", id, id2);
+			return -ENOTSUPP;
+		}
+
+		break;
+	case BCMA_CC_FLASHT_ATSER:
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_STATUS);
+		id = bcma_cc_read32(cc, BCMA_CC_FLASHDATA) & 0x3c;
+
+		for (e = bcma_sflash_at_tbl; e->name; e++) {
+			if (e->id == id)
+				break;
+		}
+		if (!e->name) {
+			bcma_err(bus, "Unsupported Atmel serial flash (id: 0x%X)\n", id);
+			return -ENOTSUPP;
+		}
+
+		break;
+	default:
+		bcma_err(bus, "Unsupported flash type\n");
+		return -ENOTSUPP;
+	}
+
+	sflash->window = BCMA_SFLASH;
+	sflash->blocksize = e->blocksize;
+	sflash->numblocks = e->numblocks;
+	sflash->size = sflash->blocksize * sflash->numblocks;
+	sflash->present = true;
+
+	bcma_info(bus, "Found %s serial flash (size: %dKiB, blocksize: 0x%X, blocks: %d)\n",
+		  e->name, sflash->size / 1024, sflash->blocksize,
+		  sflash->numblocks);
+
+	/* Prepare platform device, but don't register it yet. It's too early,
+	 * malloc (required by device_private_init) is not available yet. */
+	bcma_sflash_dev.resource[0].end = bcma_sflash_dev.resource[0].start +
+					  sflash->size;
+	bcma_sflash_dev.dev.platform_data = sflash;
+
 	return 0;
 }

drivers/bcma/main.c

@@ -7,6 +7,7 @@
 
 #include "bcma_private.h"
 #include <linux/module.h>
+#include <linux/platform_device.h>
 #include <linux/bcma/bcma.h>
 #include <linux/slab.h>
 
@@ -136,6 +137,14 @@ static int bcma_register_cores(struct bcma_bus *bus)
 		dev_id++;
 	}
 
+#ifdef CONFIG_BCMA_SFLASH
+	if (bus->drv_cc.sflash.present) {
+		err = platform_device_register(&bcma_sflash_dev);
+		if (err)
+			bcma_err(bus, "Error registering serial flash\n");
+	}
+#endif
+
 	return 0;
 }
 

include/linux/bcma/bcma_driver_chipcommon.h

@@ -509,6 +509,16 @@ struct bcma_pflash {
 	u32 window_size;
 };
 
+#ifdef CONFIG_BCMA_SFLASH
+struct bcma_sflash {
+	bool present;
+	u32 window;
+	u32 blocksize;
+	u16 numblocks;
+	u32 size;
+};
+#endif
+
 struct bcma_serial_port {
 	void *regs;
 	unsigned long clockspeed;
@@ -529,6 +539,9 @@ struct bcma_drv_cc {
 	struct bcma_chipcommon_pmu pmu;
 #ifdef CONFIG_BCMA_DRIVER_MIPS
 	struct bcma_pflash pflash;
+#ifdef CONFIG_BCMA_SFLASH
+	struct bcma_sflash sflash;
+#endif
 
 	int nr_serial_ports;
 	struct bcma_serial_port serial_ports[4];

include/linux/bcma/bcma_regs.h

@@ -85,4 +85,6 @@
 							 * (2 ZettaBytes), high 32 bits
 							 */
 
+#define BCMA_SFLASH			0x1c000000
+
 #endif /* LINUX_BCMA_REGS_H_ */