ARM: 6886/1: mmc, Add zboot from eSD support for SuperH Mobile ARM

This allows a ROM-able zImage to be written to eSD and for SuperH Mobile
ARM to boot directly from the SDHI hardware block.

This is achieved by the MaskROM loading the first portion of the image into
MERAM and then jumping to it.  This portion contains loader code which
copies the entire image to SDRAM and jumps to it. From there the zImage
boot code proceeds as normal, uncompressing the image into its final
location and then jumping to it.

Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 95 insertions, 0 deletions

diff --git a/arch/arm/boot/compressed/sdhi-sh7372.c b/arch/arm/boot/compressed/sdhi-sh7372.c
new file mode 100644
index 000000000000..d403a8b24d7f
--- /dev/null
+++ b/arch/arm/boot/compressed/sdhi-sh7372.c
@@ -0,0 +1,95 @@
+/*
+ * SuperH Mobile SDHI
+ *
+ * Copyright (C) 2010 Magnus Damm
+ * Copyright (C) 2010 Kuninori Morimoto
+ * Copyright (C) 2010 Simon Horman
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Parts inspired by u-boot
+ */
+
+#include <linux/io.h>
+#include <mach/mmc.h>
+#include <linux/mmc/boot.h>
+#include <linux/mmc/tmio.h>
+
+#include "sdhi-shmobile.h"
+
+#define PORT179CR       0xe60520b3
+#define PORT180CR       0xe60520b4
+#define PORT181CR       0xe60520b5
+#define PORT182CR       0xe60520b6
+#define PORT183CR       0xe60520b7
+#define PORT184CR       0xe60520b8
+
+#define SMSTPCR3        0xe615013c
+
+#define CR_INPUT_ENABLE 0x10
+#define CR_FUNCTION1    0x01
+
+#define SDHI1_BASE	(void __iomem *)0xe6860000
+#define SDHI_BASE	SDHI1_BASE
+
+/*  SuperH Mobile SDHI loader
+ *
+ * loads the zImage from an SD card starting from block 0
+ * on physical partition 1
+ *
+ * The image must be start with a vrl4 header and
+ * the zImage must start at offset 512 of the image. That is,
+ * at block 1 (=byte 512) of physical partition 1
+ *
+ * Use the following line to write the vrl4 formated zImage
+ * to an SD card
+ * # dd if=vrl4.out of=/dev/sdx bs=512
+ */
+asmlinkage void mmc_loader(unsigned short *buf, unsigned long len)
+{
+	int high_capacity;
+
+	mmc_init_progress();
+
+	mmc_update_progress(MMC_PROGRESS_ENTER);
+        /* Initialise SDHI1 */
+        /* PORT184CR: GPIO_FN_SDHICMD1 Control */
+        __raw_writeb(CR_FUNCTION1, PORT184CR);
+        /* PORT179CR: GPIO_FN_SDHICLK1 Control */
+        __raw_writeb(CR_INPUT_ENABLE|CR_FUNCTION1, PORT179CR);
+        /* PORT181CR: GPIO_FN_SDHID1_3 Control */
+        __raw_writeb(CR_FUNCTION1, PORT183CR);
+        /* PORT182CR: GPIO_FN_SDHID1_2 Control */
+        __raw_writeb(CR_FUNCTION1, PORT182CR);
+        /* PORT183CR: GPIO_FN_SDHID1_1 Control */
+        __raw_writeb(CR_FUNCTION1, PORT181CR);
+        /* PORT180CR: GPIO_FN_SDHID1_0 Control */
+        __raw_writeb(CR_FUNCTION1, PORT180CR);
+
+        /* Enable clock to SDHI1 hardware block */
+        __raw_writel(__raw_readl(SMSTPCR3) & ~(1 << 13), SMSTPCR3);
+
+	/* setup SDHI hardware */
+	mmc_update_progress(MMC_PROGRESS_INIT);
+	high_capacity = sdhi_boot_init(SDHI_BASE);
+	if (high_capacity < 0)
+		goto err;
+
+	mmc_update_progress(MMC_PROGRESS_LOAD);
+	/* load kernel */
+	if (sdhi_boot_do_read(SDHI_BASE, high_capacity,
+			      0, /* Kernel is at block 1 */
+			      (len + TMIO_BBS - 1) / TMIO_BBS, buf))
+		goto err;
+
+        /* Disable clock to SDHI1 hardware block */
+        __raw_writel(__raw_readl(SMSTPCR3) & (1 << 13), SMSTPCR3);
+
+	mmc_update_progress(MMC_PROGRESS_DONE);
+
+	return;
+err:
+	for(;;);
+}