[PATCH v8 04/10] arm_ffa: efi: unmap RX/TX buffers

Abdellatif El Khlifi
2022-11-22T13:19:24Z

unmap RX/TX buffers at ExitBootServices()

Unmapping the RX/TX buffers created by u-boot is needed before EFI
runtime.

At EFI runtime the linux kernel takes care of allocating its own RX/TX
buffers and registering them with the secure world.

Secure world should be using the RX/TX buffers created by the kernel.
So, RX/TX buffers created by u-boot must be unmapped.

Signed-off-by: Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
Cc: Tom Rini <trini@konsulko.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Cc: Jens Wiklander <jens.wiklander@linaro.org>

---

Changelog:
===============

v8: pass NULL device pointer to the FF-A bus operation
v7: replace debug() by log_err()

lib/efi_loader/efi_boottime.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 253f9f75ef..8949aca250 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -3,6 +3,9 @@
* EFI application boot time services
*
* Copyright (c) 2016 Alexander Graf
+ *
+ * (C) Copyright 2022 ARM Limited
+ * Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
*/

#include <common.h>
@@ -23,6 +26,10 @@
#include <asm/setjmp.h>
#include <linux/libfdt_env.h>

+#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
+#include <arm_ffa.h>
+#endif
+
DECLARE_GLOBAL_DATA_PTR;

/* Task priority level */
@@ -2178,6 +2185,12 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);
}

+#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
+ /* unmap FF-A RX/TX buffers */
+ if (ffa_bus_ops_get()->rxtx_unmap(NULL))
+ log_err("Can't unmap FF-A RX/TX buffers\n");
+#endif
+
/* Patch out unsupported runtime function */
efi_runtime_detach();

--
2.17.1