[PATCH 2/3] ACPI: Implement a generic FFH Opregion handler
Sudeep Holla
sudeep.holla at arm.com
Thu Jun 16 02:01:05 PDT 2022
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 at 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
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 1e34f846508f..c1cf40b7d22b 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -567,6 +567,16 @@ 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
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index b5a8d3e00a52..d2fc0587e218 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -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
diff --git a/drivers/acpi/acpi_ffh.c b/drivers/acpi/acpi_ffh.c
new file mode 100644
index 000000000000..19aff808bbb8
--- /dev/null
+++ b/drivers/acpi/acpi_ffh.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Author: Sudeep Holla <sudeep.holla at 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");
+}
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 86fa61a21826..84734c8cc714 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -298,6 +298,8 @@ EXPORT_SYMBOL_GPL(osc_cpc_flexible_adr_space_confirmed);
bool osc_sb_native_usb4_support_confirmed;
EXPORT_SYMBOL_GPL(osc_sb_native_usb4_support_confirmed);
+bool osc_sb_ffh_opregion_support_confirmed;
+
bool osc_sb_cppc_not_supported;
static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
@@ -384,6 +386,8 @@ 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);
@@ -1397,6 +1401,8 @@ 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();
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 4f82a5bc6d98..471c42a6044c 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -580,6 +580,7 @@ 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;
@@ -1463,6 +1464,12 @@ 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);
--
2.36.1
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