1 files changed, 90 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/xload-mmc.c b/arch/arm/mach-at91/xload-mmc.c
new file mode 100644
index 0000000000..42341fa54b
--- /dev/null
+++ b/arch/arm/mach-at91/xload-mmc.c
@@ -0,0 +1,90 @@
+#include <common.h>
+#include <mach/xload.h>
+#include <mach/sama5_bootsource.h>
+#include <mach/hardware.h>
+#include <mach/sama5d2_ll.h>
+#include <mach/gpio.h>
+#include <linux/sizes.h>
+#include <asm/cache.h>
+#include <pbl.h>
+
+static void __naked __noreturn xload_bb(void __noreturn (*bb)(void), u32 r4)
+{
+	asm volatile("mov r4, %0" : : "r"(r4) : );
+	asm volatile("bx  %0"     : : "r"(bb) : );
+}
+
+static void at91_fat_start_image(struct pbl_bio *bio,
+				 void *buf, unsigned int len,
+				 u32 r4)
+{
+	void __noreturn (*bb)(void);
+	int ret;
+
+	ret = pbl_fat_load(bio, "barebox.bin", buf, len);
+	if (ret < 0) {
+		pr_err("pbl_fat_load: error %d\n", ret);
+		return;
+	}
+
+	bb = buf;
+
+	sync_caches_for_execution();
+
+	xload_bb(bb, r4);
+}
+
+static const struct sdhci_instance {
+	void __iomem *base;
+	unsigned id;
+	u8 periph;
+	s8 pins[15];
+} sdhci_instances[] = {
+	[0] = {
+		.base = SAMA5D2_BASE_SDHC0, .id = SAMA5D2_ID_SDMMC0, .periph = AT91_MUX_PERIPH_A,
+		.pins = { 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 13, 10, 11, 12, -1 }
+	},
+	[1] = {
+		.base = SAMA5D2_BASE_SDHC1, .id = SAMA5D2_ID_SDMMC1, .periph = AT91_MUX_PERIPH_E,
+		.pins = { 18, 19, 20, 21, 22, 28, 30, -1 }
+	},
+};
+
+/**
+ * sama5d2_sdhci_start_image - Load and start an image from FAT-formatted SDHCI
+ * @r4: value of r4 passed by BootROM
+ */
+void __noreturn sama5d2_sdhci_start_image(u32 r4)
+{
+	void *buf = (void *)SAMA5_DDRCS;
+	const struct sdhci_instance *instance;
+	struct pbl_bio bio;
+	const s8 *pin;
+	int ret;
+
+	ret = sama5_bootsource_instance(r4);
+	if (ret > 1)
+		panic("Couldn't determine boot MCI instance\n");
+
+	instance = &sdhci_instances[ret];
+
+	sama5d2_pmc_enable_periph_clock(SAMA5D2_ID_PIOA);
+	for (pin = instance->pins; *pin >= 0; pin++) {
+		at91_mux_pio4_set_periph(SAMA5D2_BASE_PIOA,
+					 BIT(*pin), instance->periph);
+	}
+
+	sama5d2_pmc_enable_periph_clock(instance->id);
+	sama5d2_pmc_enable_generic_clock(instance->id, AT91_PMC_GCKCSS_UPLL_CLK, 1);
+
+	ret = at91_sdhci_bio_init(&bio, instance->base);
+	if (ret)
+		goto out_panic;
+
+	/* TODO: eMMC boot partition handling: they are not FAT-formatted */
+
+	at91_fat_start_image(&bio, buf, SZ_16M, r4);
+
+out_panic:
+	panic("FAT chainloading failed\n");
+}