arm: imx: make bmode command work with SPL/U-Boot combo

The bmode command forces the SoC to use a specific boot device by writing its boot mode into SRC_GPR9, and notifying the SoC of the change using SRC_GPR10[28] bit: if the bit is on, bootROM uses the value in SRC_GPR9 instead of SRC_SMBR1 to determine the boot device.

SPL on the other hand is oblivious to this distinction, so once the bootROM loads SPL from the device configured in SRC_GPR10, SPL will attempt to load U-Boot from the device configured in SRC_SMBR1, which is not updated by the bootROM to the value in SRC_GPR9.

The result is that the selected boot device is not used across all the boot stages.

Update spl_boot_device() to look at gpr9 when necessary.

Signed-off-by Nikita Kiryanov <[email protected]>

Cc Stefano Babic <[email protected]>

Cc Troy Kisky <[email protected]>

Cc Tim Harvey <[email protected]>

Cc Eric Nelson <[email protected]>

Cc Fabio Estevam <[email protected]>

Cc Heiko Schocher <[email protected]>

---
  arch/arm/cpu/armv7/mx6/soc.c | 4 ++--
  arch/arm/imx-common/spl.c    | 5 +++--
  2 files changed, 5 insertions(+), 4 deletions(-)

arch/arm/cpu/armv7/mx6/soc.c +2 -2

index dd5aaa2..07ae79e 100644
@@ -333,8 +333,8 @@ void boot_mode_apply(unsigned cfg_val)
  /*
   * cfg_val will be used for
   * Boot_cfg4[7:0]:Boot_cfg3[7:0]:Boot_cfg2[7:0]:Boot_cfg1[7:0]
- * After reset, if GPR10[28] is 1, ROM will copy GPR9[25:0]
- * to SBMR1, which will determine the boot device.
+ * After reset, if GPR10[28] is 1, ROM will use GPR9[25:0]
+ * instead of SBMR1 to determine the boot device.
   */
  const struct boot_mode soc_boot_modes[] = {
  	{"normal",	MAKE_CFGVAL(0x00, 0x00, 0x00, 0x00)},

arch/arm/imx-common/spl.c +3 -2

index 9d3c31a..477c38c 100644
@@ -14,11 +14,12 @@
  #include <spl.h>
 
  #if defined(CONFIG_MX6)
-/* determine boot device from SRC_SBMR1 register (BOOT_CFG[4:1]) */
+/* determine boot device from SRC_SBMR1 (BOOT_CFG[4:1]) or SRC_GPR9 register */
  u32 spl_boot_device(void)
  {
  	struct src *psrc = (struct src *)SRC_BASE_ADDR;
-	unsigned reg = readl(&psrc->sbmr1);
+	unsigned int gpr10_boot = readl(&psrc->gpr10) & (1 << 28);
+	unsigned reg = gpr10_boot ? readl(&psrc->gpr9) : readl(&psrc->sbmr1);
 
  	/* BOOT_CFG1[7:4] - see IMX6DQRM Table 8-8 */
  	switch ((reg & 0x000000FF) >> 4) {

The bmode command forces the SoC to use a specific boot device by writing its boot mode into SRC_GPR9, and notifying the SoC of the change using SRC_GPR10[28] bit: if the bit is on, bootROM uses the value in SRC_GPR9 instead of SRC_SMBR1 to determine the boot device.

SPL on the other hand is oblivious to this distinction, so once the bootROM loads SPL from the device configured in SRC_GPR10, SPL will attempt to load U-Boot from the device configured in SRC_SMBR1, which is not updated by the bootROM to the value in SRC_GPR9.

The result is that the selected boot device is not used across all the boot stages.

Update spl_boot_device() to look at gpr9 when necessary.

Signed-off-by Nikita Kiryanov <[email protected]>

Cc Stefano Babic <[email protected]>

Cc Troy Kisky <[email protected]>

Cc Tim Harvey <[email protected]>

Cc Eric Nelson <[email protected]>

Cc Fabio Estevam <[email protected]>

Cc Heiko Schocher <[email protected]>

---