From 475fb4e8b2f4444d1d7b406ff3a7d21bc89a1e6f Mon Sep 17 00:00:00 2001 From: Octavian Purdila Date: Fri, 8 Jul 2016 19:13:12 +0300 Subject: efi / ACPI: load SSTDs from EFI variables This patch allows SSDTs to be loaded from EFI variables. It works by specifying the EFI variable name containing the SSDT to be loaded. All variables with the same name (regardless of the vendor GUID) will be loaded. Note that we can't use acpi_install_table and we must rely on the dynamic ACPI table loading and bus re-scanning mechanisms. That is because I2C/SPI controllers are initialized earlier then the EFI subsystems and all I2C/SPI ACPI devices are enumerated when the I2C/SPI controllers are initialized. Signed-off-by: Octavian Purdila Reviewed-by: Matt Fleming Signed-off-by: Rafael J. Wysocki --- drivers/firmware/efi/efi.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 96 insertions(+) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 05509f3aaee8..8730fd475bf3 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -24,6 +24,9 @@ #include #include #include +#include +#include +#include #include @@ -195,6 +198,96 @@ static void generic_ops_unregister(void) efivars_unregister(&generic_efivars); } +#if IS_ENABLED(CONFIG_ACPI) +#define EFIVAR_SSDT_NAME_MAX 16 +static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; +static int __init efivar_ssdt_setup(char *str) +{ + if (strlen(str) < sizeof(efivar_ssdt)) + memcpy(efivar_ssdt, str, strlen(str)); + else + pr_warn("efivar_ssdt: name too long: %s\n", str); + return 0; +} +__setup("efivar_ssdt=", efivar_ssdt_setup); + +static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor, + unsigned long name_size, void *data) +{ + struct efivar_entry *entry; + struct list_head *list = data; + char utf8_name[EFIVAR_SSDT_NAME_MAX]; + int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size); + + ucs2_as_utf8(utf8_name, name, limit - 1); + if (strncmp(utf8_name, efivar_ssdt, limit) != 0) + return 0; + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return 0; + + memcpy(entry->var.VariableName, name, name_size); + memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t)); + + efivar_entry_add(entry, list); + + return 0; +} + +static __init int efivar_ssdt_load(void) +{ + LIST_HEAD(entries); + struct efivar_entry *entry, *aux; + unsigned long size; + void *data; + int ret; + + ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries); + + list_for_each_entry_safe(entry, aux, &entries, list) { + pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, + &entry->var.VendorGuid); + + list_del(&entry->list); + + ret = efivar_entry_size(entry, &size); + if (ret) { + pr_err("failed to get var size\n"); + goto free_entry; + } + + data = kmalloc(size, GFP_KERNEL); + if (!data) + goto free_entry; + + ret = efivar_entry_get(entry, NULL, &size, data); + if (ret) { + pr_err("failed to get var data\n"); + goto free_data; + } + + ret = acpi_load_table(data); + if (ret) { + pr_err("failed to load table: %d\n", ret); + goto free_data; + } + + goto free_entry; + +free_data: + kfree(data); + +free_entry: + kfree(entry); + } + + return ret; +} +#else +static inline int efivar_ssdt_load(void) { return 0; } +#endif + /* * We register the efi subsystem with the firmware subsystem and the * efivars subsystem with the efi subsystem, if the system was booted with @@ -218,6 +311,9 @@ static int __init efisubsys_init(void) if (error) goto err_put; + if (efi_enabled(EFI_RUNTIME_SERVICES)) + efivar_ssdt_load(); + error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); if (error) { pr_err("efi: Sysfs attribute export failed with error %d.\n", -- cgit v1.2.3 From c2a25c141f4e80debd8eec3e9a5f9d25daedb54f Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 19 Jul 2016 18:52:57 +0100 Subject: drivers: firmware: psci: initialise idle states using ACPI LPI This patch adds support for initialisation of PSCI CPUIdle states from Low Power Idle(_LPI) entries in the ACPI tables when acpi is enabled. Acked-by: Lorenzo Pieralisi Signed-off-by: Sudeep Holla Signed-off-by: Rafael J. Wysocki --- drivers/firmware/psci.c | 66 +++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 59 insertions(+), 7 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index 03e04582791c..8263429e21b8 100644 --- a/drivers/firmware/psci.c +++ b/drivers/firmware/psci.c @@ -13,6 +13,7 @@ #define pr_fmt(fmt) "psci: " fmt +#include #include #include #include @@ -256,13 +257,6 @@ static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu) u32 *psci_states; struct device_node *state_node; - /* - * If the PSCI cpu_suspend function hook has not been initialized - * idle states must not be enabled, so bail out - */ - if (!psci_ops.cpu_suspend) - return -EOPNOTSUPP; - /* Count idle states */ while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states", count))) { @@ -310,11 +304,69 @@ free_mem: return ret; } +#ifdef CONFIG_ACPI +#include + +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) +{ + int i, count; + u32 *psci_states; + struct acpi_lpi_state *lpi; + struct acpi_processor *pr = per_cpu(processors, cpu); + + if (unlikely(!pr || !pr->flags.has_lpi)) + return -EINVAL; + + count = pr->power.count - 1; + if (count <= 0) + return -ENODEV; + + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); + if (!psci_states) + return -ENOMEM; + + for (i = 0; i < count; i++) { + u32 state; + + lpi = &pr->power.lpi_states[i + 1]; + /* + * Only bits[31:0] represent a PSCI power_state while + * bits[63:32] must be 0x0 as per ARM ACPI FFH Specification + */ + state = lpi->address; + if (!psci_power_state_is_valid(state)) { + pr_warn("Invalid PSCI power state %#x\n", state); + kfree(psci_states); + return -EINVAL; + } + psci_states[i] = state; + } + /* Idle states parsed correctly, initialize per-cpu pointer */ + per_cpu(psci_power_state, cpu) = psci_states; + return 0; +} +#else +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) +{ + return -EINVAL; +} +#endif + int psci_cpu_init_idle(unsigned int cpu) { struct device_node *cpu_node; int ret; + /* + * If the PSCI cpu_suspend function hook has not been initialized + * idle states must not be enabled, so bail out + */ + if (!psci_ops.cpu_suspend) + return -EOPNOTSUPP; + + if (!acpi_disabled) + return psci_acpi_cpu_init_idle(cpu); + cpu_node = of_get_cpu_node(cpu, NULL); if (!cpu_node) return -ENODEV; -- cgit v1.2.3