HREF+ SD support

On HREF+, SD card power supply is controlled by the Vaux3 regulator.  In
order to enable the power supply, port the AB8500 PRCMU I2C read/write
code from Linux to U-Boot, and then write the appropriate registers via
those functions.

Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Change-Id: I470f3da694e6ea0e3e0e16571c3048066f0a4309
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/388
Reviewed-by: Michael BRANDT <michael.brandt@stericsson.com>
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
Tested-by: Jonas ABERG <jonas.aberg@stericsson.com>

1 files changed, 70 insertions, 2 deletions

diff --git a/board/st/u8500/u8500.c b/board/st/u8500/u8500.c
index cf6b70bdc..02df1ed53 100644
--- a/board/st/u8500/u8500.c
+++ b/board/st/u8500/u8500.c
@@ -13,6 +13,7 @@
 #include <asm/errno.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/hardware.h>
+#include <asm/arch/ab8500.h>
 #include "gpio.h"
 
 #include "common.h"
@@ -126,13 +127,22 @@ void show_boot_progress(int progress)
 }
 #endif
 
-int u8500_is_earlydrop(void)
+static unsigned int read_asicid(void)
 {
 	unsigned int *address = (void *)U8500_BOOTROM_BASE
 				+ U8500_BOOTROM_ASIC_ID_OFFSET;
+	return readl(address);
+}
 
+int u8500_is_earlydrop(void)
+{
 	/* 0x01 for ED, 0xA0 for v1 */
-	return (readl(address) & 0xff) == 0x01;
+	return (read_asicid() & 0xff) == 0x01;
+}
+
+int cpu_is_u8500v11(void)
+{
+	return read_asicid() == 0x008500A1;
 }
 
 /*
@@ -190,6 +200,62 @@ unsigned int addr_vall_arr[] = {
 };
 
 #ifdef BOARD_LATE_INIT
+#ifdef CONFIG_MMC
+
+#define LDO_VAUX3_MASK		0x3
+#define LDO_VAUX3_ENABLE	0x1
+#define VAUX3_VOLTAGE_2_9V	0xd
+
+static int hrefplus_mmc_power_init(void)
+{
+	int ret;
+	int val;
+
+	if (!cpu_is_u8500v11())
+		return 0;
+
+	/*
+	 * On v1.1 HREF boards (HREF+), Vaux3 needs to be enabled for the SD
+	 * card to work.  This is done by enabling the regulators in the AB8500
+	 * via PRCMU I2C transactions.
+	 *
+	 * This code is derived from the handling of AB8500_LDO_VAUX3 in
+	 * ab8500_ldo_enable() and ab8500_ldo_disable() in Linux.
+	 *
+	 * Turn off and delay is required to have it work across soft reboots.
+	 */
+
+	ret = ab8500_read(AB8500_REGU_CTRL2, AB8500_REGU_VRF1VAUX3_REGU_REG);
+	if (ret < 0)
+		goto out;
+
+	val = ret;
+
+	/* Turn off */
+	ret = ab8500_write(AB8500_REGU_CTRL2, AB8500_REGU_VRF1VAUX3_REGU_REG,
+			   val & ~LDO_VAUX3_MASK);
+	if (ret < 0)
+		goto out;
+
+	udelay(10 * 1000);
+
+	/* Set the voltage to 2.9V */
+	ret = ab8500_write(AB8500_REGU_CTRL2,
+			   AB8500_REGU_VRF1VAUX3_SEL_REG, VAUX3_VOLTAGE_2_9V);
+	if (ret < 0)
+		goto out;
+
+	val = val & ~LDO_VAUX3_MASK;
+	val = val | LDO_VAUX3_ENABLE;
+
+	/* Turn on the supply */
+	ret = ab8500_write(AB8500_REGU_CTRL2,
+			   AB8500_REGU_VRF1VAUX3_REGU_REG, val);
+
+out:
+	return ret;
+}
+#endif
 /*
  * called after all initialisation were done, but before the generic
  * mmc_initialize().
@@ -219,6 +285,8 @@ int board_late_init(void)
 		setenv("board_id", "1");
 	}
 #ifdef CONFIG_MMC
+	hrefplus_mmc_power_init();
+
 	/*
 	 * config extended GPIO pins for level shifter and
 	 * SDMMC_ENABLE