@@ -564,6 +564,16 @@ config ACPI_PCC
Enable this feature if you want to set up and install the PCC Address
Space handler to handle PCC OpRegion in the firmware.
+config ACPI_FFH
+ bool "ACPI FFH Address Space"
+ default n
+ help
+ The FFH(Fixed Function Hardware) Address Space also referred as FFH
+ Operation Region allows to define platform specific opregion.
+
+ Enable this feature if you want to set up and install the FFH Address
+ Space handler to handle FFH OpRegion in the firmware.
+
source "drivers/acpi/pmic/Kconfig"
config ACPI_VIOT
@@ -68,6 +68,7 @@ acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o
acpi-$(CONFIG_ACPI_WATCHDOG) += acpi_watchdog.o
acpi-$(CONFIG_ACPI_PRMT) += prmt.o
acpi-$(CONFIG_ACPI_PCC) += acpi_pcc.o
+acpi-$(CONFIG_ACPI_FFH) += acpi_ffh.o
# Address translation
acpi-$(CONFIG_ACPI_ADXL) += acpi_adxl.o
new file mode 100644
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Author: Sudeep Holla <sudeep.holla@arm.com>
+ * Copyright 2022 Arm Limited
+ */
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/completion.h>
+#include <linux/idr.h>
+#include <linux/io.h>
+
+#include <linux/arm-smccc.h>
+
+static struct acpi_ffh_info ffh_ctx;
+
+int __weak acpi_ffh_address_space_arch_setup(void *handler_ctxt,
+ void **region_ctxt)
+{
+ return -EOPNOTSUPP;
+}
+
+int __weak acpi_ffh_address_space_arch_handler(acpi_integer *value,
+ void *region_context)
+{
+ return -EOPNOTSUPP;
+}
+
+static acpi_status
+acpi_ffh_address_space_setup(acpi_handle region_handle, u32 function,
+ void *handler_context, void **region_context)
+{
+ return acpi_ffh_address_space_arch_setup(handler_context,
+ region_context);
+}
+
+static acpi_status
+acpi_ffh_address_space_handler(u32 function, acpi_physical_address addr,
+ u32 bits, acpi_integer *value,
+ void *handler_context, void *region_context)
+{
+ return acpi_ffh_address_space_arch_handler(value, region_context);
+}
+
+void __init acpi_init_ffh(void)
+{
+ acpi_status status;
+
+ status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
+ ACPI_ADR_SPACE_FIXED_HARDWARE,
+ &acpi_ffh_address_space_handler,
+ &acpi_ffh_address_space_setup,
+ &ffh_ctx);
+ if (ACPI_FAILURE(status))
+ pr_alert("OperationRegion handler could not be installed\n");
+}
@@ -300,6 +300,8 @@ EXPORT_SYMBOL_GPL(osc_sb_native_usb4_support_confirmed);
bool osc_sb_cppc2_support_acked;
+bool osc_sb_ffh_opregion_support_confirmed;
+
static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
static void acpi_bus_osc_negotiate_platform_control(void)
{
@@ -383,6 +385,8 @@ static void acpi_bus_osc_negotiate_platform_control(void)
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
osc_cpc_flexible_adr_space_confirmed =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
+ osc_sb_ffh_opregion_support_confirmed =
+ capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_FFH_OPR_SUPPORT;
}
kfree(context.ret.pointer);
@@ -1408,6 +1412,8 @@ static int __init acpi_init(void)
disable_acpi();
return result;
}
+ if (osc_sb_ffh_opregion_support_confirmed)
+ acpi_init_ffh();
pci_mmcfg_late_init();
acpi_iort_init();
@@ -586,6 +586,7 @@ acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context);
#define OSC_SB_CPC_FLEXIBLE_ADR_SPACE 0x00004000
#define OSC_SB_NATIVE_USB4_SUPPORT 0x00040000
#define OSC_SB_PRM_SUPPORT 0x00200000
+#define OSC_SB_FFH_OPR_SUPPORT 0x00400000
extern bool osc_sb_apei_support_acked;
extern bool osc_pc_lpi_support_confirmed;
@@ -1488,6 +1489,12 @@ void acpi_init_pcc(void);
static inline void acpi_init_pcc(void) { }
#endif
+#ifdef CONFIG_ACPI_FFH
+void acpi_init_ffh(void);
+#else
+static inline void acpi_init_ffh(void) { }
+#endif
+
#ifdef CONFIG_ACPI
extern void acpi_device_notify(struct device *dev);
extern void acpi_device_notify_remove(struct device *dev);
This registers the FFH OpRegion handler before ACPI tables are loaded. The platform support for the same is checked via Platform-Wide OSPM Capabilities(OSC) before registering the OpRegion handler. It relies on the special context data passed to offset and the length. However the interpretation of the values is platform/architecture specific. This generic handler just passed all the information to the platform/architecture specific callback. It also implements the default callbacks which return as not supported. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> --- drivers/acpi/Kconfig | 10 ++++++++ drivers/acpi/Makefile | 1 + drivers/acpi/acpi_ffh.c | 55 +++++++++++++++++++++++++++++++++++++++++ drivers/acpi/bus.c | 6 +++++ include/linux/acpi.h | 7 ++++++ 5 files changed, 79 insertions(+) create mode 100644 drivers/acpi/acpi_ffh.c