Merge tag 'u-boot-atmel-fixes-2020.07-a' of https://gitlab.denx.de/u-boot/custodians...

[oweals/u-boot.git] / arch / arm / mach-rockchip / bootrom.c

diff --git a/arch/arm/mach-rockchip/bootrom.c b/arch/arm/mach-rockchip/bootrom.c
index 8380e4e00613b8c2cd8e4fc587226b51d6dba2e1..b36e559e8719eba9dcfcf94609cf0e7f1cf179d0 100644 (file)
--- a/arch/arm/mach-rockchip/bootrom.c
+++ b/arch/arm/mach-rockchip/bootrom.c
@@ -1,16 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0+
 /**
  * Copyright (c) 2017 Google, Inc
- *
- * SPDX-License-Identifier:    GPL-2.0+
  */
 
 #include <common.h>
-#include <asm/arch/bootrom.h>
+#include <hang.h>
+#include <asm/arch-rockchip/bootrom.h>
+#include <asm/arch-rockchip/boot_mode.h>
+#include <asm/cache.h>
+#include <asm/io.h>
+#include <asm/setjmp.h>
+#include <asm/system.h>
+
+/*
+ * Force the jmp_buf to the data-section, as .bss will not be valid
+ * when save_boot_params is invoked.
+ */
+static jmp_buf brom_ctx __section(".data");
+
+static void _back_to_bootrom(enum rockchip_bootrom_cmd brom_cmd)
+{
+       longjmp(brom_ctx, brom_cmd);
+}
 
-void back_to_bootrom(void)
+void back_to_bootrom(enum rockchip_bootrom_cmd brom_cmd)
 {
 #if CONFIG_IS_ENABLED(LIBCOMMON_SUPPORT)
        puts("Returning to boot ROM...\n");
 #endif
-       _back_to_bootrom_s();
+       _back_to_bootrom(brom_cmd);
+}
+
+/*
+ * we back to bootrom download mode if get a
+ * BOOT_BROM_DOWNLOAD flag in boot mode register
+ *
+ * note: the boot mode register is configured by
+ * application(next stage bootloader, kernel, etc),
+ * and the bootrom never check this register, so we need
+ * to check it and back to bootrom at very early bootstage(before
+ * some basic configurations(such as interrupts) been
+ * changed by TPL/SPL, as the bootrom download operation
+ * relies on many default settings(such as interrupts) by
+ * itself.
+ */
+static bool check_back_to_brom_dnl_flag(void)
+{
+       u32 boot_mode;
+
+       if (CONFIG_ROCKCHIP_BOOT_MODE_REG) {
+               boot_mode = readl(CONFIG_ROCKCHIP_BOOT_MODE_REG);
+               if (boot_mode == BOOT_BROM_DOWNLOAD) {
+                       writel(0, CONFIG_ROCKCHIP_BOOT_MODE_REG);
+                       return true;
+               }
+       }
+
+       return false;
+}
+
+/*
+ * All Rockchip BROM implementations enter with a valid stack-pointer,
+ * so this can safely be implemented in C (providing a single
+ * implementation both for ARMv7 and AArch64).
+ */
+int save_boot_params(void)
+{
+       int  ret = setjmp(brom_ctx);
+
+       switch (ret) {
+       case 0:
+               if (check_back_to_brom_dnl_flag())
+                       _back_to_bootrom(BROM_BOOT_ENTER_DNL);
+               /*
+                * This is the initial pass through this function
+                * (i.e. saving the context), setjmp just setup up the
+                * brom_ctx: transfer back into the startup-code at
+                * 'save_boot_params_ret' and let the compiler know
+                * that this will not return.
+                */
+               save_boot_params_ret();
+               while (true)
+                       /* does not return */;
+               break;
+
+       case BROM_BOOT_NEXTSTAGE:
+               /*
+                * To instruct the BROM to boot the next stage, we
+                * need to return 0 to it: i.e. we need to rewrite
+                * the return code once more.
+                */
+               ret = 0;
+               break;
+       case BROM_BOOT_ENTER_DNL:
+               /*
+                * A non-zero return value will instruct the BROM enter
+                * download mode.
+                */
+               ret = 1;
+               break;
+       default:
+#if CONFIG_IS_ENABLED(LIBCOMMON_SUPPORT)
+               puts("FATAL: unexpected command to back_to_bootrom()\n");
+#endif
+               hang();
+       };
+
+       return ret;
 }