ARM: bcm2835: fix get_timer() to return ms

Apparently, CONFIG_SYS_HZ must be 1000. Change this, and fix the timer
driver to conform to this.

Have the timer implementation export a custom API get_timer_us() for use
by the BCM2835 MMC API, which needs us resolution for a HW workaround.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>

arch/arm/cpu/arm1176/bcm2835/timer.c

@@ -23,7 +23,7 @@ int timer_init(void)
 	return 0;
 }
 
-ulong get_timer(ulong base)
+ulong get_timer_us(ulong base)
 {
 	struct bcm2835_timer_regs *regs =
 		(struct bcm2835_timer_regs *)BCM2835_TIMER_PHYSADDR;
@@ -31,6 +31,14 @@ ulong get_timer(ulong base)
 	return readl(&regs->clo) - base;
 }
 
+ulong get_timer(ulong base)
+{
+	ulong us = get_timer_us(0);
+	us /= (1000000 / CONFIG_SYS_HZ);
+	us -= base;
+	return us;
+}
+
 unsigned long long get_ticks(void)
 {
 	return get_timer(0);
@@ -46,10 +54,10 @@ void __udelay(unsigned long usec)
 	ulong endtime;
 	signed long diff;
 
-	endtime = get_timer(0) + usec;
+	endtime = get_timer_us(0) + usec;
 
 	do {
-		ulong now = get_timer(0);
+		ulong now = get_timer_us(0);
 		diff = endtime - now;
 	} while (diff >= 0);
 }

arch/arm/include/asm/arch-bcm2835/timer.h

@@ -34,4 +34,6 @@ struct bcm2835_timer_regs {
 #define BCM2835_TIMER_CS_M1	(1 << 1)
 #define BCM2835_TIMER_CS_M0	(1 << 0)
 
+extern ulong get_timer_us(ulong base);
+
 #endif

drivers/mmc/bcm2835_sdhci.c

@@ -39,6 +39,7 @@
 #include <common.h>
 #include <malloc.h>
 #include <sdhci.h>
+#include <asm/arch/timer.h>
 
 /* 400KHz is max freq for card ID etc. Use that as min */
 #define MIN_FREQ 400000
@@ -67,11 +68,11 @@ static inline void bcm2835_sdhci_raw_writel(struct sdhci_host *host, u32 val,
 	 * (Which is just as well - otherwise we'd have to nobble the DMA engine
 	 * too)
 	 */
-	while (get_timer(bcm_host->last_write) < bcm_host->twoticks_delay)
+	while (get_timer_us(bcm_host->last_write) < bcm_host->twoticks_delay)
 		;
 
 	writel(val, host->ioaddr + reg);
-	bcm_host->last_write = get_timer(0);
+	bcm_host->last_write = get_timer_us(0);
 }
 
 static inline u32 bcm2835_sdhci_raw_readl(struct sdhci_host *host, int reg)

include/configs/rpi_b.h

@@ -31,7 +31,7 @@
 #define CONFIG_MACH_TYPE		MACH_TYPE_BCM2708
 
 /* Timer */
-#define CONFIG_SYS_HZ			1000000
+#define CONFIG_SYS_HZ			1000
 
 /* Memory layout */
 #define CONFIG_NR_DRAM_BANKS		1