[PATCH] arm: socfpga: arria10: Add save_boot_params()

[Ley Foon Tan]

Add save_boot_params() to save reset status value from bootrom.

Bootrom will clear the status register in reset manager and stores the
reset status value in shared memory. Bootrom stores shared data at last
2KB of onchip RAM.

This function save reset status provided by BootROM to rst_mgr_status.
More information about reset status register value can be found in reset
manager register description.

When running in debugger without Bootrom, r0 to r3 are random values.
So, skip save the value when r0 is not BootROM shared data address.

Signed-off-by: Ley Foon Tan <ley.foon.tan at intel.com>
---
 arch/arm/mach-socfpga/spl_a10.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/arch/arm/mach-socfpga/spl_a10.c b/arch/arm/mach-socfpga/spl_a10.c
index d9ef851054..867b1c906e 100644
--- a/arch/arm/mach-socfpga/spl_a10.c
+++ b/arch/arm/mach-socfpga/spl_a10.c
@@ -33,6 +33,36 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#define BOOTROM_SHARED_MEM_ADDR		(CONFIG_SYS_INIT_RAM_ADDR + 0x40000 \
+					 - 0x800)
+#define RST_STATUS_SHARED_ADDR		(BOOTROM_SHARED_MEM_ADDR + 0x438)
+u32 rst_mgr_status __section(.data);
+
+/*
+ * Bootrom will clear the status register in reset manager and stores the
+ * reset status value in shared memory. Bootrom stores shared data at last
+ * 2KB of onchip RAM.
+ * This function save reset status provided by BootROM to rst_mgr_status.
+ * More information about reset status register value can be found in reset
+ * manager register description.
+ * When running in debugger without Bootrom, r0 to r3 are random values.
+ * So, skip save the value when r0 is not BootROM shared data address.
+ *
+ * r0 - Contains the pointer to the shared memory block. The shared
+ *	memory block is located in the top 2 KB of on-chip RAM.
+ * r1 - contains the length of the shared memory.
+ * r2 - unused and set to 0x0.
+ * r3 - points to the version block.
+ */
+void save_boot_params(unsigned long r0, unsigned long r1, unsigned long r2,
+		      unsigned long r3)
+{
+	if (r0 == BOOTROM_SHARED_MEM_ADDR)
+		rst_mgr_status = readl(RST_STATUS_SHARED_ADDR);
+
+	save_boot_params_ret();
+}
+
 u32 spl_boot_device(void)
 {
 	const u32 bsel = readl(socfpga_get_sysmgr_addr() + SYSMGR_A10_BOOTINFO);
-- 
2.19.0