x86: sysreset: Separate out the EFI code

The EFI implementation of reset sits inside the driver and is called
directly from outside the driver, breaking the normal driver-model
conventions. Worse, it passed NULL as the device pointer, hoping that
the called function won't use it, which breaks as soon as code is added
to use it.

Separate out the implementation to improve the situation enough to allow
a future patch to add new sysreset features.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>

drivers/sysreset/sysreset_x86.c

@@ -12,8 +12,7 @@
 #include <asm/processor.h>
 #include <efi_loader.h>
 
-static __efi_runtime int x86_sysreset_request(struct udevice *dev,
-					      enum sysreset_t type)
+static int x86_sysreset_request(struct udevice *dev, enum sysreset_t type)
 {
 	int value;
 
@@ -39,11 +38,18 @@ void __efi_runtime EFIAPI efi_reset_system(
 			efi_status_t reset_status,
 			unsigned long data_size, void *reset_data)
 {
+	int value;
+
+	/*
+	 * inline this code since we are not caused in the context of a
+	 * udevice and passing NULL to x86_sysreset_request() is too horrible.
+	 */
 	if (reset_type == EFI_RESET_COLD ||
 		 reset_type == EFI_RESET_PLATFORM_SPECIFIC)
-		x86_sysreset_request(NULL, SYSRESET_COLD);
-	else if (reset_type == EFI_RESET_WARM)
-		x86_sysreset_request(NULL, SYSRESET_WARM);
+		value = SYS_RST | RST_CPU | FULL_RST;
+	else /* assume EFI_RESET_WARM since we cannot return an error */
+		value = SYS_RST | RST_CPU;
+	outb(value, IO_PORT_RESET);
 
 	/* TODO EFI_RESET_SHUTDOWN */