[PATCH v3 19/20] powerpc/rtas: introduce rtas_function_token() API
Nathan Lynch via B4 Submission Endpoint
devnull+nathanl.linux.ibm.com at kernel.org
Sat Feb 11 05:42:07 AEDT 2023
From: Nathan Lynch <nathanl at linux.ibm.com>
Users of rtas_token() supply a string argument that can't be validated
at build time. A typo or misspelling has to be caught by inspection or
by observing wrong behavior at runtime.
Since the core RTAS code now has consolidated the names of all
possible RTAS functions and mapped them to their tokens, token lookup
can be implemented using symbolic constants to index a static array.
So introduce rtas_function_token(), a replacement API which does that,
along with a rtas_service_present()-equivalent helper,
rtas_function_implemented(). Callers supply an opaque predefined
function handle which is used internally to index the function
table. Typos or other inappropriate arguments yield build errors, and
the function handle is a type that can't be easily confused with RTAS
tokens or other integer types.
Signed-off-by: Nathan Lynch <nathanl at linux.ibm.com>
---
arch/powerpc/include/asm/rtas.h | 99 +++++++++++++++++++++++++++++++++++++++++
arch/powerpc/kernel/rtas.c | 28 +++++++++++-
2 files changed, 126 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/rtas.h b/arch/powerpc/include/asm/rtas.h
index f03891891a2d..3abe15ac79db 100644
--- a/arch/powerpc/include/asm/rtas.h
+++ b/arch/powerpc/include/asm/rtas.h
@@ -101,6 +101,100 @@ enum rtas_function_index {
RTAS_FNIDX__WRITE_PCI_CONFIG,
};
+/*
+ * Opaque handle for client code to refer to RTAS functions. All valid
+ * function handles are build-time constants prefixed with RTAS_FN_.
+ */
+typedef struct {
+ const enum rtas_function_index index;
+} rtas_fn_handle_t;
+
+
+#define rtas_fn_handle(x_) ((const rtas_fn_handle_t) { .index = x_, })
+
+#define RTAS_FN_CHECK_EXCEPTION rtas_fn_handle(RTAS_FNIDX__CHECK_EXCEPTION)
+#define RTAS_FN_DISPLAY_CHARACTER rtas_fn_handle(RTAS_FNIDX__DISPLAY_CHARACTER)
+#define RTAS_FN_EVENT_SCAN rtas_fn_handle(RTAS_FNIDX__EVENT_SCAN)
+#define RTAS_FN_FREEZE_TIME_BASE rtas_fn_handle(RTAS_FNIDX__FREEZE_TIME_BASE)
+#define RTAS_FN_GET_POWER_LEVEL rtas_fn_handle(RTAS_FNIDX__GET_POWER_LEVEL)
+#define RTAS_FN_GET_SENSOR_STATE rtas_fn_handle(RTAS_FNIDX__GET_SENSOR_STATE)
+#define RTAS_FN_GET_TERM_CHAR rtas_fn_handle(RTAS_FNIDX__GET_TERM_CHAR)
+#define RTAS_FN_GET_TIME_OF_DAY rtas_fn_handle(RTAS_FNIDX__GET_TIME_OF_DAY)
+#define RTAS_FN_IBM_ACTIVATE_FIRMWARE rtas_fn_handle(RTAS_FNIDX__IBM_ACTIVATE_FIRMWARE)
+#define RTAS_FN_IBM_CBE_START_PTCAL rtas_fn_handle(RTAS_FNIDX__IBM_CBE_START_PTCAL)
+#define RTAS_FN_IBM_CBE_STOP_PTCAL rtas_fn_handle(RTAS_FNIDX__IBM_CBE_STOP_PTCAL)
+#define RTAS_FN_IBM_CHANGE_MSI rtas_fn_handle(RTAS_FNIDX__IBM_CHANGE_MSI)
+#define RTAS_FN_IBM_CLOSE_ERRINJCT rtas_fn_handle(RTAS_FNIDX__IBM_CLOSE_ERRINJCT)
+#define RTAS_FN_IBM_CONFIGURE_BRIDGE rtas_fn_handle(RTAS_FNIDX__IBM_CONFIGURE_BRIDGE)
+#define RTAS_FN_IBM_CONFIGURE_CONNECTOR rtas_fn_handle(RTAS_FNIDX__IBM_CONFIGURE_CONNECTOR)
+#define RTAS_FN_IBM_CONFIGURE_KERNEL_DUMP rtas_fn_handle(RTAS_FNIDX__IBM_CONFIGURE_KERNEL_DUMP)
+#define RTAS_FN_IBM_CONFIGURE_PE rtas_fn_handle(RTAS_FNIDX__IBM_CONFIGURE_PE)
+#define RTAS_FN_IBM_CREATE_PE_DMA_WINDOW rtas_fn_handle(RTAS_FNIDX__IBM_CREATE_PE_DMA_WINDOW)
+#define RTAS_FN_IBM_DISPLAY_MESSAGE rtas_fn_handle(RTAS_FNIDX__IBM_DISPLAY_MESSAGE)
+#define RTAS_FN_IBM_ERRINJCT rtas_fn_handle(RTAS_FNIDX__IBM_ERRINJCT)
+#define RTAS_FN_IBM_EXTI2C rtas_fn_handle(RTAS_FNIDX__IBM_EXTI2C)
+#define RTAS_FN_IBM_GET_CONFIG_ADDR_INFO rtas_fn_handle(RTAS_FNIDX__IBM_GET_CONFIG_ADDR_INFO)
+#define RTAS_FN_IBM_GET_CONFIG_ADDR_INFO2 rtas_fn_handle(RTAS_FNIDX__IBM_GET_CONFIG_ADDR_INFO2)
+#define RTAS_FN_IBM_GET_DYNAMIC_SENSOR_STATE rtas_fn_handle(RTAS_FNIDX__IBM_GET_DYNAMIC_SENSOR_STATE)
+#define RTAS_FN_IBM_GET_INDICES rtas_fn_handle(RTAS_FNIDX__IBM_GET_INDICES)
+#define RTAS_FN_IBM_GET_RIO_TOPOLOGY rtas_fn_handle(RTAS_FNIDX__IBM_GET_RIO_TOPOLOGY)
+#define RTAS_FN_IBM_GET_SYSTEM_PARAMETER rtas_fn_handle(RTAS_FNIDX__IBM_GET_SYSTEM_PARAMETER)
+#define RTAS_FN_IBM_GET_VPD rtas_fn_handle(RTAS_FNIDX__IBM_GET_VPD)
+#define RTAS_FN_IBM_GET_XIVE rtas_fn_handle(RTAS_FNIDX__IBM_GET_XIVE)
+#define RTAS_FN_IBM_INT_OFF rtas_fn_handle(RTAS_FNIDX__IBM_INT_OFF)
+#define RTAS_FN_IBM_INT_ON rtas_fn_handle(RTAS_FNIDX__IBM_INT_ON)
+#define RTAS_FN_IBM_IO_QUIESCE_ACK rtas_fn_handle(RTAS_FNIDX__IBM_IO_QUIESCE_ACK)
+#define RTAS_FN_IBM_LPAR_PERFTOOLS rtas_fn_handle(RTAS_FNIDX__IBM_LPAR_PERFTOOLS)
+#define RTAS_FN_IBM_MANAGE_FLASH_IMAGE rtas_fn_handle(RTAS_FNIDX__IBM_MANAGE_FLASH_IMAGE)
+#define RTAS_FN_IBM_MANAGE_STORAGE_PRESERVATION rtas_fn_handle(RTAS_FNIDX__IBM_MANAGE_STORAGE_PRESERVATION)
+#define RTAS_FN_IBM_NMI_INTERLOCK rtas_fn_handle(RTAS_FNIDX__IBM_NMI_INTERLOCK)
+#define RTAS_FN_IBM_NMI_REGISTER rtas_fn_handle(RTAS_FNIDX__IBM_NMI_REGISTER)
+#define RTAS_FN_IBM_OPEN_ERRINJCT rtas_fn_handle(RTAS_FNIDX__IBM_OPEN_ERRINJCT)
+#define RTAS_FN_IBM_OPEN_SRIOV_ALLOW_UNFREEZE rtas_fn_handle(RTAS_FNIDX__IBM_OPEN_SRIOV_ALLOW_UNFREEZE)
+#define RTAS_FN_IBM_OPEN_SRIOV_MAP_PE_NUMBER rtas_fn_handle(RTAS_FNIDX__IBM_OPEN_SRIOV_MAP_PE_NUMBER)
+#define RTAS_FN_IBM_OS_TERM rtas_fn_handle(RTAS_FNIDX__IBM_OS_TERM)
+#define RTAS_FN_IBM_PARTNER_CONTROL rtas_fn_handle(RTAS_FNIDX__IBM_PARTNER_CONTROL)
+#define RTAS_FN_IBM_PHYSICAL_ATTESTATION rtas_fn_handle(RTAS_FNIDX__IBM_PHYSICAL_ATTESTATION)
+#define RTAS_FN_IBM_PLATFORM_DUMP rtas_fn_handle(RTAS_FNIDX__IBM_PLATFORM_DUMP)
+#define RTAS_FN_IBM_POWER_OFF_UPS rtas_fn_handle(RTAS_FNIDX__IBM_POWER_OFF_UPS)
+#define RTAS_FN_IBM_QUERY_INTERRUPT_SOURCE_NUMBER rtas_fn_handle(RTAS_FNIDX__IBM_QUERY_INTERRUPT_SOURCE_NUMBER)
+#define RTAS_FN_IBM_QUERY_PE_DMA_WINDOW rtas_fn_handle(RTAS_FNIDX__IBM_QUERY_PE_DMA_WINDOW)
+#define RTAS_FN_IBM_READ_PCI_CONFIG rtas_fn_handle(RTAS_FNIDX__IBM_READ_PCI_CONFIG)
+#define RTAS_FN_IBM_READ_SLOT_RESET_STATE rtas_fn_handle(RTAS_FNIDX__IBM_READ_SLOT_RESET_STATE)
+#define RTAS_FN_IBM_READ_SLOT_RESET_STATE2 rtas_fn_handle(RTAS_FNIDX__IBM_READ_SLOT_RESET_STATE2)
+#define RTAS_FN_IBM_REMOVE_PE_DMA_WINDOW rtas_fn_handle(RTAS_FNIDX__IBM_REMOVE_PE_DMA_WINDOW)
+#define RTAS_FN_IBM_RESET_PE_DMA_WINDOWS rtas_fn_handle(RTAS_FNIDX__IBM_RESET_PE_DMA_WINDOWS)
+#define RTAS_FN_IBM_SCAN_LOG_DUMP rtas_fn_handle(RTAS_FNIDX__IBM_SCAN_LOG_DUMP)
+#define RTAS_FN_IBM_SET_DYNAMIC_INDICATOR rtas_fn_handle(RTAS_FNIDX__IBM_SET_DYNAMIC_INDICATOR)
+#define RTAS_FN_IBM_SET_EEH_OPTION rtas_fn_handle(RTAS_FNIDX__IBM_SET_EEH_OPTION)
+#define RTAS_FN_IBM_SET_SLOT_RESET rtas_fn_handle(RTAS_FNIDX__IBM_SET_SLOT_RESET)
+#define RTAS_FN_IBM_SET_SYSTEM_PARAMETER rtas_fn_handle(RTAS_FNIDX__IBM_SET_SYSTEM_PARAMETER)
+#define RTAS_FN_IBM_SET_XIVE rtas_fn_handle(RTAS_FNIDX__IBM_SET_XIVE)
+#define RTAS_FN_IBM_SLOT_ERROR_DETAIL rtas_fn_handle(RTAS_FNIDX__IBM_SLOT_ERROR_DETAIL)
+#define RTAS_FN_IBM_SUSPEND_ME rtas_fn_handle(RTAS_FNIDX__IBM_SUSPEND_ME)
+#define RTAS_FN_IBM_TUNE_DMA_PARMS rtas_fn_handle(RTAS_FNIDX__IBM_TUNE_DMA_PARMS)
+#define RTAS_FN_IBM_UPDATE_FLASH_64_AND_REBOOT rtas_fn_handle(RTAS_FNIDX__IBM_UPDATE_FLASH_64_AND_REBOOT)
+#define RTAS_FN_IBM_UPDATE_NODES rtas_fn_handle(RTAS_FNIDX__IBM_UPDATE_NODES)
+#define RTAS_FN_IBM_UPDATE_PROPERTIES rtas_fn_handle(RTAS_FNIDX__IBM_UPDATE_PROPERTIES)
+#define RTAS_FN_IBM_VALIDATE_FLASH_IMAGE rtas_fn_handle(RTAS_FNIDX__IBM_VALIDATE_FLASH_IMAGE)
+#define RTAS_FN_IBM_WRITE_PCI_CONFIG rtas_fn_handle(RTAS_FNIDX__IBM_WRITE_PCI_CONFIG)
+#define RTAS_FN_NVRAM_FETCH rtas_fn_handle(RTAS_FNIDX__NVRAM_FETCH)
+#define RTAS_FN_NVRAM_STORE rtas_fn_handle(RTAS_FNIDX__NVRAM_STORE)
+#define RTAS_FN_POWER_OFF rtas_fn_handle(RTAS_FNIDX__POWER_OFF)
+#define RTAS_FN_PUT_TERM_CHAR rtas_fn_handle(RTAS_FNIDX__PUT_TERM_CHAR)
+#define RTAS_FN_QUERY_CPU_STOPPED_STATE rtas_fn_handle(RTAS_FNIDX__QUERY_CPU_STOPPED_STATE)
+#define RTAS_FN_READ_PCI_CONFIG rtas_fn_handle(RTAS_FNIDX__READ_PCI_CONFIG)
+#define RTAS_FN_RTAS_LAST_ERROR rtas_fn_handle(RTAS_FNIDX__RTAS_LAST_ERROR)
+#define RTAS_FN_SET_INDICATOR rtas_fn_handle(RTAS_FNIDX__SET_INDICATOR)
+#define RTAS_FN_SET_POWER_LEVEL rtas_fn_handle(RTAS_FNIDX__SET_POWER_LEVEL)
+#define RTAS_FN_SET_TIME_FOR_POWER_ON rtas_fn_handle(RTAS_FNIDX__SET_TIME_FOR_POWER_ON)
+#define RTAS_FN_SET_TIME_OF_DAY rtas_fn_handle(RTAS_FNIDX__SET_TIME_OF_DAY)
+#define RTAS_FN_START_CPU rtas_fn_handle(RTAS_FNIDX__START_CPU)
+#define RTAS_FN_STOP_SELF rtas_fn_handle(RTAS_FNIDX__STOP_SELF)
+#define RTAS_FN_SYSTEM_REBOOT rtas_fn_handle(RTAS_FNIDX__SYSTEM_REBOOT)
+#define RTAS_FN_THAW_TIME_BASE rtas_fn_handle(RTAS_FNIDX__THAW_TIME_BASE)
+#define RTAS_FN_WRITE_PCI_CONFIG rtas_fn_handle(RTAS_FNIDX__WRITE_PCI_CONFIG)
+
#define RTAS_UNKNOWN_SERVICE (-1)
#define RTAS_INSTANTIATE_MAX (1ULL<<30) /* Don't instantiate rtas at/above this value */
@@ -307,6 +401,11 @@ extern void (*rtas_flash_term_hook)(int);
extern struct rtas_t rtas;
+s32 rtas_function_token(const rtas_fn_handle_t handle);
+static inline bool rtas_function_implemented(const rtas_fn_handle_t handle)
+{
+ return rtas_function_token(handle) != RTAS_UNKNOWN_SERVICE;
+}
extern int rtas_token(const char *service);
extern int rtas_service_present(const char *service);
extern int rtas_call(int token, int, int, int *, ...);
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 1f80f0b8a9ad..bb6f5370c279 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -453,6 +453,32 @@ static struct rtas_function rtas_function_table[] __ro_after_init = {
},
};
+/**
+ * rtas_function_token() - RTAS function token lookup.
+ * @handle: Function handle, e.g. RTAS_FN_EVENT_SCAN.
+ *
+ * Context: Any context.
+ * Return: the token value for the function if implemented by this platform,
+ * otherwise RTAS_UNKNOWN_SERVICE.
+ */
+s32 rtas_function_token(const rtas_fn_handle_t handle)
+{
+ const size_t index = handle.index;
+ const bool out_of_bounds = index >= ARRAY_SIZE(rtas_function_table);
+
+ if (WARN_ONCE(out_of_bounds, "invalid function index %zu", index))
+ return RTAS_UNKNOWN_SERVICE;
+ /*
+ * Various drivers attempt token lookups on non-RTAS
+ * platforms.
+ */
+ if (!rtas.dev)
+ return RTAS_UNKNOWN_SERVICE;
+
+ return rtas_function_table[index].token;
+}
+EXPORT_SYMBOL_GPL(rtas_function_token);
+
static int rtas_function_cmp(const void *a, const void *b)
{
const struct rtas_function *f1 = a;
@@ -1011,7 +1037,7 @@ static int ibm_errinjct_token;
* @....: List of @nargs input parameters.
*
* Invokes the RTAS function indicated by @token, which the caller
- * should obtain via rtas_token().
+ * should obtain via rtas_function_token().
*
* The @nargs and @nret arguments must match the number of input and
* output parameters specified for the RTAS function.
--
2.39.1
More information about the Linuxppc-dev
mailing list