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efi_loader: save global data pointer on RISC-V

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On RISC-V the global data pointer is stored in register gp. When a UEFI
binary calls the EFI API we have to restore it.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This commit is contained in:
Heinrich Schuchardt 2020-09-10 12:22:54 +02:00
parent 6b9966e1aa
commit d68d7f47a9
1 changed files with 9 additions and 9 deletions
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18
lib/efi_loader/efi_boottime.c
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@ -42,9 +42,9 @@ LIST_HEAD(efi_register_notify_events);
/* Handle of the currently executing image */
static efi_handle_t current_image;
#ifdef CONFIG_ARM
#if defined(CONFIG_ARM) || defined(CONFIG_RISCV)
/*
* The "gd" pointer lives in a register on ARM and AArch64 that we declare
* The "gd" pointer lives in a register on ARM and RISC-V that we declare
* fixed when compiling U-Boot. However, the payload does not know about that
* restriction so we need to manually swap its and our view of that register on
* EFI callback entry/exit.
@ -86,7 +86,7 @@ static efi_status_t EFIAPI efi_disconnect_controller(
int __efi_entry_check(void)
{
int ret = entry_count++ == 0;
#ifdef CONFIG_ARM
#if defined(CONFIG_ARM) || defined(CONFIG_RISCV)
assert(efi_gd);
app_gd = gd;
set_gd(efi_gd);
@ -98,7 +98,7 @@ int __efi_entry_check(void)
int __efi_exit_check(void)
{
int ret = --entry_count == 0;
#ifdef CONFIG_ARM
#if defined(CONFIG_ARM) || defined(CONFIG_RISCV)
set_gd(app_gd);
#endif
return ret;
@ -107,7 +107,7 @@ int __efi_exit_check(void)
/**
* efi_save_gd() - save global data register
*
* On the ARM architecture gd is mapped to a fixed register (r9 or x18).
* On the ARM and RISC-V architectures gd is mapped to a fixed register.
* As this register may be overwritten by an EFI payload we save it here
* and restore it on every callback entered.
*
@ -115,7 +115,7 @@ int __efi_exit_check(void)
*/
void efi_save_gd(void)
{
#ifdef CONFIG_ARM
#if defined(CONFIG_ARM) || defined(CONFIG_RISCV)
efi_gd = gd;
#endif
}
@ -123,13 +123,13 @@ void efi_save_gd(void)
/**
* efi_restore_gd() - restore global data register
*
* On the ARM architecture gd is mapped to a fixed register (r9 or x18).
* On the ARM and RISC-V architectures gd is mapped to a fixed register.
* Restore it after returning from the UEFI world to the value saved via
* efi_save_gd().
*/
void efi_restore_gd(void)
{
#ifdef CONFIG_ARM
#if defined(CONFIG_ARM) || defined(CONFIG_RISCV)
/* Only restore if we're already in EFI context */
if (!efi_gd)
return;
@ -2920,7 +2920,7 @@ efi_status_t EFIAPI efi_start_image(efi_handle_t image_handle,
* us to the current line. This implies that the second half
* of the EFI_CALL macro has not been executed.
*/
#ifdef CONFIG_ARM
#if defined(CONFIG_ARM) || defined(CONFIG_RISCV)
/*
* efi_exit() called efi_restore_gd(). We have to undo this
* otherwise __efi_entry_check() will put the wrong value into