u-boot/drivers/firmware/psci.c
Jon Hunter fb264efbd2 firmware: PSCI: Fix PSCI support for OF live trees
When CONFIG_OF_LIVE is enabled, dev_of_offset() cannot be used and
if used returns an invalid offset. This causes the call to
fdt_stringlist_get() in the psci_probe() to fail to read the 'method'
property from the PSCI node for the device and hence prevents PSCI
from working. Fix this by using the ofnode_read_string() API instead
of the fdt_stringlist_get() because this will handle reading the
property both when CONFIG_OF_LIVE is enabled or disabled.

Due to the above problem and since commit 81ea00838c ("efi_loader:
PSCI reset and shutdown") was added, the EFI system reset has been
broken for Tegra210 and Tegra196 platforms. This also fixes the EFI
system reset for these Tegra platforms.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
2020-06-18 13:14:50 -07:00

164 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017 Masahiro Yamada <yamada.masahiro@socionext.com>
*
* Based on drivers/firmware/psci.c from Linux:
* Copyright (C) 2015 ARM Limited
*/
#include <common.h>
#include <command.h>
#include <dm.h>
#include <irq_func.h>
#include <log.h>
#include <dm/lists.h>
#include <efi_loader.h>
#include <linux/delay.h>
#include <linux/libfdt.h>
#include <linux/arm-smccc.h>
#include <linux/errno.h>
#include <linux/printk.h>
#include <linux/psci.h>
#define DRIVER_NAME "psci"
#define PSCI_METHOD_HVC 1
#define PSCI_METHOD_SMC 2
int __efi_runtime_data psci_method;
unsigned long __efi_runtime invoke_psci_fn
(unsigned long function_id, unsigned long arg0,
unsigned long arg1, unsigned long arg2)
{
struct arm_smccc_res res;
/*
* In the __efi_runtime we need to avoid the switch statement. In some
* cases the compiler creates lookup tables to implement switch. These
* tables are not correctly relocated when SetVirtualAddressMap is
* called.
*/
if (psci_method == PSCI_METHOD_SMC)
arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
else if (psci_method == PSCI_METHOD_HVC)
arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
else
res.a0 = PSCI_RET_DISABLED;
return res.a0;
}
static int psci_bind(struct udevice *dev)
{
/* No SYSTEM_RESET support for PSCI 0.1 */
if (device_is_compatible(dev, "arm,psci-0.2") ||
device_is_compatible(dev, "arm,psci-1.0")) {
int ret;
/* bind psci-sysreset optionally */
ret = device_bind_driver(dev, "psci-sysreset", "psci-sysreset",
NULL);
if (ret)
pr_debug("PSCI System Reset was not bound.\n");
}
return 0;
}
static int psci_probe(struct udevice *dev)
{
const char *method;
method = ofnode_read_string(dev_ofnode(dev), "method");
if (!method) {
pr_warn("missing \"method\" property\n");
return -ENXIO;
}
if (!strcmp("hvc", method)) {
psci_method = PSCI_METHOD_HVC;
} else if (!strcmp("smc", method)) {
psci_method = PSCI_METHOD_SMC;
} else {
pr_warn("invalid \"method\" property: %s\n", method);
return -EINVAL;
}
return 0;
}
/**
* void do_psci_probe() - probe PSCI firmware driver
*
* Ensure that psci_method is initialized.
*/
static void __maybe_unused do_psci_probe(void)
{
struct udevice *dev;
uclass_get_device_by_name(UCLASS_FIRMWARE, DRIVER_NAME, &dev);
}
#if IS_ENABLED(CONFIG_EFI_LOADER) && IS_ENABLED(CONFIG_PSCI_RESET)
efi_status_t efi_reset_system_init(void)
{
do_psci_probe();
return EFI_SUCCESS;
}
void __efi_runtime EFIAPI efi_reset_system(enum efi_reset_type reset_type,
efi_status_t reset_status,
unsigned long data_size,
void *reset_data)
{
if (reset_type == EFI_RESET_COLD ||
reset_type == EFI_RESET_WARM ||
reset_type == EFI_RESET_PLATFORM_SPECIFIC) {
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
} else if (reset_type == EFI_RESET_SHUTDOWN) {
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
}
while (1)
;
}
#endif /* IS_ENABLED(CONFIG_EFI_LOADER) && IS_ENABLED(CONFIG_PSCI_RESET) */
#ifdef CONFIG_PSCI_RESET
void reset_misc(void)
{
do_psci_probe();
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
}
#endif /* CONFIG_PSCI_RESET */
#ifdef CONFIG_CMD_POWEROFF
int do_poweroff(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
{
do_psci_probe();
puts("poweroff ...\n");
udelay(50000); /* wait 50 ms */
disable_interrupts();
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
enable_interrupts();
log_err("Power off not supported on this platform\n");
return CMD_RET_FAILURE;
}
#endif
static const struct udevice_id psci_of_match[] = {
{ .compatible = "arm,psci" },
{ .compatible = "arm,psci-0.2" },
{ .compatible = "arm,psci-1.0" },
{},
};
U_BOOT_DRIVER(psci) = {
.name = DRIVER_NAME,
.id = UCLASS_FIRMWARE,
.of_match = psci_of_match,
.bind = psci_bind,
.probe = psci_probe,
};