sunxi: spl: Detect at runtime where SPL was read from

Make possible using a single `u-boot-sunxi-with-spl.bin` binary for both NAND
memory and SD card. Detection where SPL was read from is implemented in
`spl_boot_device`.

Signed-off-by: Daniel Kochmański <dkochmanski@turtle-solutions.eu>
CC: Roy Spliet <r.spliet@ultimaker.com>
Cc: Ian Campbell <ijc@hellion.org.uk>
[hdegoede@redhat.com: Some small coding style fixes]
Acked-by: Hans De Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/arch/arm/cpu/armv7/sunxi/board.c b/arch/arm/cpu/armv7/sunxi/board.c
index 5f39aa0..f01846e 100644 (file)
--- a/arch/arm/cpu/armv7/sunxi/board.c
+++ b/arch/arm/cpu/armv7/sunxi/board.c
@@ -11,6 +11,7 @@
  */
 
 #include <common.h>
+#include <mmc.h>
 #include <i2c.h>
 #include <serial.h>
 #ifdef CONFIG_SPL_BUILD
@@ -22,6 +23,7 @@
 #include <asm/arch/gpio.h>
 #include <asm/arch/sys_proto.h>
 #include <asm/arch/timer.h>
+#include <asm/arch/mmc.h>
 
 #include <linux/compiler.h>
 
@@ -121,17 +123,18 @@ void s_init(void)
 }
 
 #ifdef CONFIG_SPL_BUILD
+DECLARE_GLOBAL_DATA_PTR;
+
 /* The sunxi internal brom will try to loader external bootloader
  * from mmc0, nand flash, mmc2.
- * Unfortunately we can't check how SPL was loaded so assume
- * it's always the first SD/MMC controller
  */
 u32 spl_boot_device(void)
 {
+       struct mmc *mmc0, *mmc1;
        /*
-        * When booting from the SD card, the "eGON.BT0" signature is expected
-        * to be found in memory at the address 0x0004 (see the "mksunxiboot"
-        * tool, which generates this header).
+        * When booting from the SD card or NAND memory, the "eGON.BT0"
+        * signature is expected to be found in memory at the address 0x0004
+        * (see the "mksunxiboot" tool, which generates this header).
         *
         * When booting in the FEL mode over USB, this signature is patched in
         * memory and replaced with something else by the 'fel' tool. This other
@@ -139,15 +142,40 @@ u32 spl_boot_device(void)
         * valid bootable SD card image (because the BROM would refuse to
         * execute the SPL in this case).
         *
-        * This branch is just making a decision at runtime whether to load
-        * the main u-boot binary from the SD card (if the "eGON.BT0" signature
-        * is found) or return to the FEL code in the BROM to wait and receive
-        * the main u-boot binary over USB.
+        * This checks for the signature and if it is not found returns to
+        * the FEL code in the BROM to wait and receive the main u-boot
+        * binary over USB. If it is found, it determines where SPL was
+        * read from.
         */
-       if (readl(4) == 0x4E4F4765 && readl(8) == 0x3054422E) /* eGON.BT0 */
-               return BOOT_DEVICE_MMC1;
-       else
+       if (readl(4) != 0x4E4F4765 || readl(8) != 0x3054422E) /* eGON.BT0 */
                return BOOT_DEVICE_BOARD;
+
+       /* The BROM will try to boot from mmc0 first, so try that first. */
+       mmc_initialize(gd->bd);
+       mmc0 = find_mmc_device(0);
+       if (sunxi_mmc_has_egon_boot_signature(mmc0))
+               return BOOT_DEVICE_MMC1;
+
+       /* Fallback to booting NAND if enabled. */
+       if (IS_ENABLED(CONFIG_SPL_NAND_SUPPORT))
+               return BOOT_DEVICE_NAND;
+
+       if (CONFIG_MMC_SUNXI_SLOT_EXTRA == 2) {
+               mmc1 = find_mmc_device(1);
+               if (sunxi_mmc_has_egon_boot_signature(mmc1)) {
+                       /*
+                        * spl_mmc.c: spl_mmc_load_image() is hard-coded to
+                        * use find_mmc_device(0), no matter what we
+                        * return. Swap mmc0 and mmc2 to make this work.
+                        */
+                       mmc0->block_dev.dev = 1;
+                       mmc1->block_dev.dev = 0;
+                       return BOOT_DEVICE_MMC2;
+               }
+       }
+
+       panic("Could not determine boot source\n");
+       return -1;              /* Never reached */
 }
 
 /* No confirmation data available in SPL yet. Hardcode bootmode */