[PATCH 5/5] mach-ux500: add a SoC ID (serial) callback for the u8500

[Lee Jones]

With this patch applied the Export SoC Information framework
will be able to callback into u8500 Platform code in order to
probe for the SoC's unique Identification (serial) number.

Signed-off-by: Lee Jones <lee.jones at linaro.org>
---
 arch/arm/mach-ux500/cpu-db8500.c               |   16 ++++++++++++++++
 arch/arm/mach-ux500/include/mach/db8500-regs.h |    4 ++++
 2 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-ux500/cpu-db8500.c b/arch/arm/mach-ux500/cpu-db8500.c
index 655639e..9824cd3 100644
--- a/arch/arm/mach-ux500/cpu-db8500.c
+++ b/arch/arm/mach-ux500/cpu-db8500.c
@@ -167,6 +167,20 @@ static void __init db8500_add_gpios(void)
 			 IRQ_DB8500_GPIO0, &pdata);
 }
 
+static const char *db8500_get_soc_id(void)
+{
+	void __iomem *uid_base;
+	char buf[1024];
+	ssize_t sz = 0;
+	int i;
+
+	uid_base = __io_address(U8500_BB_UID_BASE);
+	for (i = 0; i < U8500_BB_UID_LENGTH; i++) {
+		sz += sprintf(buf + sz, "%08x", readl(uid_base + i * sizeof(u32)));
+	}
+	return kasprintf(GFP_KERNEL, "%s", buf);
+}
+
 static int usb_db8500_rx_dma_cfg[] = {
 	DB8500_DMA_DEV38_USB_OTG_IEP_1_9,
 	DB8500_DMA_DEV37_USB_OTG_IEP_2_10,
@@ -208,6 +222,8 @@ void __init u8500_init_devices(void)
 		"cpufreq-u8500", -1, NULL, 0, NULL, 0);
 
 	if (soc_dev) {
+		soc_dev->pfn_soc_id = db8500_get_soc_id;
+
 		for (i=0; i<ARRAY_SIZE(platform_devs); i++)
 			platform_devs[i]->dev.parent = &soc_dev->dev;
 	}
diff --git a/arch/arm/mach-ux500/include/mach/db8500-regs.h b/arch/arm/mach-ux500/include/mach/db8500-regs.h
index 0499971..f569d5c 100644
--- a/arch/arm/mach-ux500/include/mach/db8500-regs.h
+++ b/arch/arm/mach-ux500/include/mach/db8500-regs.h
@@ -166,4 +166,8 @@
 #define U8500_MODEM_BASE	0xe000000
 #define U8500_APE_BASE		0x6000000
 
+/* SoC identification number information */
+#define U8500_BB_UID_BASE (U8500_BACKUPRAM1_BASE + 0xFC0)
+#define U8500_BB_UID_LENGTH 5
+
 #endif
-- 
1.7.4.1