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-rw-r--r--arch/arm/cpu/psci-client.c190
1 files changed, 190 insertions, 0 deletions
diff --git a/arch/arm/cpu/psci-client.c b/arch/arm/cpu/psci-client.c
new file mode 100644
index 0000000..b5d0d37
--- /dev/null
+++ b/arch/arm/cpu/psci-client.c
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017 Masahiro Yamada <yamada.masahiro@socionext.com>
+ * Copyright (C) 2019 Ahmad Fatoum, Pengutronix
+ */
+
+#include <common.h>
+#include <init.h>
+#include <driver.h>
+#include <asm/psci.h>
+#include <asm/secure.h>
+#include <poweroff.h>
+#include <restart.h>
+#include <linux/arm-smccc.h>
+
+static struct restart_handler restart;
+
+static void __noreturn psci_invoke_noreturn(int function)
+{
+ int ret;
+
+ ret = psci_invoke(function, 0, 0, 0, NULL);
+
+ pr_err("psci command failed: %s\n", strerror(-ret));
+ hang();
+}
+
+static void __noreturn psci_poweroff(struct poweroff_handler *handler)
+{
+ psci_invoke_noreturn(ARM_PSCI_0_2_FN_SYSTEM_OFF);
+}
+
+static void __noreturn psci_restart(struct restart_handler *rst)
+{
+ psci_invoke_noreturn(ARM_PSCI_0_2_FN_SYSTEM_RESET);
+}
+
+static u32 version;
+int psci_get_version(void)
+{
+ if (!version)
+ return -EPROBE_DEFER;
+
+ return version;
+}
+
+static u32 (*psci_invoke_fn)(ulong, ulong, ulong, ulong);
+
+static int psci_xlate_error(s32 errnum)
+{
+ switch (errnum) {
+ case ARM_PSCI_RET_NOT_SUPPORTED:
+ return -ENOTSUPP; // Operation not supported
+ case ARM_PSCI_RET_INVAL:
+ return -EINVAL; // Invalid argument
+ case ARM_PSCI_RET_DENIED:
+ return -EPERM; // Operation not permitted
+ case ARM_PSCI_RET_ALREADY_ON:
+ return -EBUSY; // CPU already on
+ case ARM_PSCI_RET_ON_PENDING:
+ return -EALREADY; // CPU_ON in progress
+ case ARM_PSCI_RET_INTERNAL_FAILURE:
+ return -EIO; // Internal failure
+ case ARM_PSCI_RET_NOT_PRESENT:
+ return -ESRCH; // Trusted OS not present on core
+ case ARM_PSCI_RET_DISABLED:
+ return -ENODEV; // CPU is disabled
+ case ARM_PSCI_RET_INVALID_ADDRESS:
+ return -EACCES; // Bad address
+ default:
+ return errnum;
+ };
+}
+
+int psci_invoke(ulong function, ulong arg0, ulong arg1, ulong arg2,
+ ulong *result)
+{
+ ulong ret;
+ if (!psci_invoke_fn)
+ return -EPROBE_DEFER;
+
+ ret = psci_invoke_fn(function, arg0, arg1, arg2);
+ if (result)
+ *result = ret;
+
+ switch (function) {
+ case ARM_PSCI_0_2_FN_PSCI_VERSION:
+ case ARM_PSCI_1_0_FN64_STAT_RESIDENCY:
+ case ARM_PSCI_1_0_FN64_STAT_COUNT:
+ /* These don't return an error code */
+ return 0;
+ }
+
+ return psci_xlate_error(ret);
+}
+
+static u32 invoke_psci_fn_hvc(ulong function, ulong arg0, ulong arg1, ulong arg2)
+{
+ struct arm_smccc_res res;
+ arm_smccc_hvc(function, arg0, arg1, arg2, 0, 0, 0, 0, &res);
+ return res.a0;
+}
+
+static u32 invoke_psci_fn_smc(ulong function, ulong arg0, ulong arg1, ulong arg2)
+{
+ struct arm_smccc_res res;
+ arm_smccc_smc(function, arg0, arg1, arg2, 0, 0, 0, 0, &res);
+ return res.a0;
+}
+
+static int of_psci_do_fixup(struct device_node *root, void *context)
+{
+ return of_psci_fixup(root, *(u32 *)context);
+}
+
+static int __init psci_probe(struct device_d *dev)
+{
+ const char *method;
+ ulong of_version, actual_version;
+ int ret;
+
+ ret = dev_get_drvdata(dev, (const void **)&of_version);
+ if (ret)
+ return -ENODEV;
+
+ ret = of_property_read_string(dev->device_node, "method", &method);
+ if (ret) {
+ dev_warn(dev, "missing \"method\" property\n");
+ return -ENXIO;
+ }
+
+ if (!strcmp(method, "hvc")) {
+ psci_invoke_fn = invoke_psci_fn_hvc;
+ } else if (!strcmp(method, "smc")) {
+ psci_invoke_fn = invoke_psci_fn_smc;
+ } else {
+ pr_warn("invalid \"method\" property: %s\n", method);
+ return -EINVAL;
+ }
+
+
+ if (of_version < ARM_PSCI_VER(0,2)) {
+ version = of_version;
+
+ dev_info(dev, "assuming version %u.%u\n",
+ version >> 16, version & 0xffff);
+ dev_dbg(dev, "Not registering reset handler due to PSCI version\n");
+
+ return 0;
+ }
+
+ psci_invoke(ARM_PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0, &actual_version);
+ version = actual_version;
+
+ dev_info(dev, "detected version %u.%u\n",
+ version >> 16, version & 0xffff);
+
+ if (actual_version != of_version)
+ of_register_fixup(of_psci_do_fixup, &version);
+
+ ret = poweroff_handler_register_fn(psci_poweroff);
+ if (ret)
+ dev_warn(dev, "error registering poweroff handler: %s\n",
+ strerror(-ret));
+
+ restart.name = "psci";
+ restart.restart = psci_restart;
+ restart.priority = 400;
+
+ ret = restart_handler_register(&restart);
+ if (ret)
+ dev_warn(dev, "error registering restart handler: %s\n",
+ strerror(-ret));
+
+ return ret;
+}
+
+static __maybe_unused struct of_device_id psci_dt_ids[] = {
+ { .compatible = "arm,psci", .data = (void*)ARM_PSCI_VER(0,1) },
+ { .compatible = "arm,psci-0.2", .data = (void*)ARM_PSCI_VER(0,2) },
+ { .compatible = "arm,psci-1.0", .data = (void*)ARM_PSCI_VER(1,0) },
+ { /* sentinel */ },
+};
+
+static struct driver_d psci_driver = {
+ .name = "psci",
+ .probe = psci_probe,
+ .of_compatible = DRV_OF_COMPAT(psci_dt_ids),
+};
+coredevice_platform_driver(psci_driver);