arm: mvebu: Add SATA/SCSI (AHCI) support for Armada A38x

This patch adds support for the common AHCI controller on the Marvell
Armada 38x.

Tested on the Marvell DB-88F6820-GP eval board.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Luka Perkov <luka.perkov@sartura.hr>
diff --git a/arch/arm/mach-mvebu/cpu.c b/arch/arm/mach-mvebu/cpu.c
index 531d0fb..9bc9f00 100644
--- a/arch/arm/mach-mvebu/cpu.c
+++ b/arch/arm/mach-mvebu/cpu.c
@@ -6,6 +6,8 @@
 
 #include <common.h>
 #include <netdev.h>
+#include <ahci.h>
+#include <linux/mbus.h>
 #include <asm/io.h>
 #include <asm/pl310.h>
 #include <asm/arch/cpu.h>
@@ -256,6 +258,59 @@
 }
 #endif
 
+#ifdef CONFIG_SCSI_AHCI_PLAT
+#define AHCI_VENDOR_SPECIFIC_0_ADDR	0xa0
+#define AHCI_VENDOR_SPECIFIC_0_DATA	0xa4
+
+#define AHCI_WINDOW_CTRL(win)		(0x60 + ((win) << 4))
+#define AHCI_WINDOW_BASE(win)		(0x64 + ((win) << 4))
+#define AHCI_WINDOW_SIZE(win)		(0x68 + ((win) << 4))
+
+static void ahci_mvebu_mbus_config(void __iomem *base)
+{
+	const struct mbus_dram_target_info *dram;
+	int i;
+
+	dram = mvebu_mbus_dram_info();
+
+	for (i = 0; i < 4; i++) {
+		writel(0, base + AHCI_WINDOW_CTRL(i));
+		writel(0, base + AHCI_WINDOW_BASE(i));
+		writel(0, base + AHCI_WINDOW_SIZE(i));
+	}
+
+	for (i = 0; i < dram->num_cs; i++) {
+		const struct mbus_dram_window *cs = dram->cs + i;
+
+		writel((cs->mbus_attr << 8) |
+		       (dram->mbus_dram_target_id << 4) | 1,
+		       base + AHCI_WINDOW_CTRL(i));
+		writel(cs->base >> 16, base + AHCI_WINDOW_BASE(i));
+		writel(((cs->size - 1) & 0xffff0000),
+		       base + AHCI_WINDOW_SIZE(i));
+	}
+}
+
+static void ahci_mvebu_regret_option(void __iomem *base)
+{
+	/*
+	 * Enable the regret bit to allow the SATA unit to regret a
+	 * request that didn't receive an acknowlegde and avoid a
+	 * deadlock
+	 */
+	writel(0x4, base + AHCI_VENDOR_SPECIFIC_0_ADDR);
+	writel(0x80, base + AHCI_VENDOR_SPECIFIC_0_DATA);
+}
+
+void scsi_init(void)
+{
+	printf("MVEBU SATA INIT\n");
+	ahci_mvebu_mbus_config((void __iomem *)MVEBU_SATA0_BASE);
+	ahci_mvebu_regret_option((void __iomem *)MVEBU_SATA0_BASE);
+	ahci_init((void __iomem *)MVEBU_SATA0_BASE);
+}
+#endif
+
 #ifndef CONFIG_SYS_DCACHE_OFF
 void enable_caches(void)
 {
diff --git a/arch/arm/mach-mvebu/include/mach/soc.h b/arch/arm/mach-mvebu/include/mach/soc.h
index 1aeec27..e6bfbc2 100644
--- a/arch/arm/mach-mvebu/include/mach/soc.h
+++ b/arch/arm/mach-mvebu/include/mach/soc.h
@@ -51,6 +51,7 @@
 #define MVEBU_REG_PCIE_BASE	(MVEBU_REGISTER(0x40000))
 #define MVEBU_EGIGA0_BASE	(MVEBU_REGISTER(0x70000))
 #define MVEBU_EGIGA1_BASE	(MVEBU_REGISTER(0x74000))
+#define MVEBU_SATA0_BASE	(MVEBU_REGISTER(0xa8000))
 #define MVEBU_SDIO_BASE		(MVEBU_REGISTER(0xd8000))
 
 #define SDRAM_MAX_CS		4