Some BootLoaders do not support UEFI and cannot pass ACPI/SBMIOS table
addresses through UEFI, such as coreboot.
On the x86 platform, we pass the ACPI/SMBIOS table through the reserved
address segment 0xF0000, but other arches usually do not reserve this
address segment.
We have added a new firmware information transmission method named FFI
(FDT FIRMWARE INTERFACE), through FDT to obtain firmware information,
such as the base address of the ACPI and SMBIOS table.
Signed-off-by: Yunhui Cui <cuiyunhui@xxxxxxxxxxxxx>
---
MAINTAINERS | 6 +++
drivers/acpi/osl.c | 8 ++++
drivers/firmware/Kconfig | 12 +++++
drivers/firmware/Makefile | 1 +
drivers/firmware/dmi_scan.c | 96 ++++++++++++++++++++++---------------
drivers/firmware/ffi.c | 56 ++++++++++++++++++++++
include/linux/ffi.h | 15 ++++++
7 files changed, 155 insertions(+), 39 deletions(-)
create mode 100644 drivers/firmware/ffi.c
create mode 100644 include/linux/ffi.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 8d5bc223f305..94664f3b4c96 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7750,6 +7750,12 @@ F: arch/x86/platform/efi/
F: drivers/firmware/efi/
F: include/linux/efi*.h
+FDT FIRMWARE INTERFACE (FFI)
+M: Yunhui Cui cuiyunhui@xxxxxxxxxxxxx
+S: Maintained
+F: drivers/firmware/ffi.c
+F: include/linux/ffi.h
+
EXTERNAL CONNECTOR SUBSYSTEM (EXTCON)
M: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
M: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 3269a888fb7a..d45000041d2b 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -25,6 +25,7 @@
#include <linux/nmi.h>
#include <linux/acpi.h>
#include <linux/efi.h>
+#include <linux/ffi.h>
#include <linux/ioport.h>
#include <linux/list.h>
#include <linux/jiffies.h>
@@ -206,6 +207,13 @@ acpi_physical_address __init acpi_os_get_root_pointer(void)
if (pa)
return pa;
+#ifdef CONFIG_FDT_FW_INTERFACE
+ if (fdt_fwtbl.acpi20 != FDT_INVALID_FWTBL_ADDR)
+ return fdt_fwtbl.acpi20;
+ if (fdt_fwtbl.acpi != FDT_INVALID_FWTBL_ADDR)
+ return fdt_fwtbl.acpi;
+ pr_err("Fdt system description tables not found\n");
+#endif
if (efi_enabled(EFI_CONFIG_TABLES)) {
if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
return efi.acpi20;
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index b59e3041fd62..13c67b50c17a 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -303,6 +303,18 @@ config TURRIS_MOX_RWTM
other manufacturing data and also utilize the Entropy Bit Generator
for hardware random number generation.
+config FDT_FW_INTERFACE
+ bool "An interface for passing firmware info through FDT"
+ depends on OF && OF_FLATTREE
+ default n
+ help
+ When some bootloaders do not support UEFI, and the arch does not
+ support SMBIOS_ENTRY_POINT_SCAN_START, then you can enable this option
+ to support the transfer of firmware information, such as acpi, smbios
+ tables.
+
+ Say Y here if you want to pass firmware information by FDT.
+
source "drivers/firmware/arm_ffa/Kconfig"
source "drivers/firmware/broadcom/Kconfig"
source "drivers/firmware/cirrus/Kconfig"
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 28fcddcd688f..3b8b5d0868a6 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -33,6 +33,7 @@ obj-y += cirrus/
obj-y += meson/
obj-$(CONFIG_GOOGLE_FIRMWARE) += google/
obj-y += efi/
+obj-$(CONFIG_FDT_FW_INTERFACE) += ffi.o
obj-y += imx/
obj-y += psci/
obj-y += smccc/
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index 015c95a825d3..1e1a74ed7d3b 100644
--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -6,6 +6,7 @@
#include <linux/ctype.h>
#include <linux/dmi.h>
#include <linux/efi.h>
+#include <linux/ffi.h>
#include <linux/memblock.h>
#include <linux/random.h>
#include <asm/dmi.h>
@@ -655,54 +656,71 @@ static int __init dmi_smbios3_present(const u8 *buf)
return 1;
}
-static void __init dmi_scan_machine(void)
+/*
+ * According to the DMTF SMBIOS reference spec v3.0.0, it is
+ * allowed to define both the 64-bit entry point (smbios3) and
+ * the 32-bit entry point (smbios), in which case they should
+ * either both point to the same SMBIOS structure table, or the
+ * table pointed to by the 64-bit entry point should contain a
+ * superset of the table contents pointed to by the 32-bit entry
+ * point (section 5.2)
+ * This implies that the 64-bit entry point should have
+ * precedence if it is defined and supported by the OS. If we
+ * have the 64-bit entry point, but fail to decode it, fall
+ * back to the legacy one (if available)
+ */
+static int __init dmi_sacn_smbios(unsigned long smbios3, unsigned long smbios)
{
- char __iomem *p, *q;
+ char __iomem *p;
char buf[32];
+ #define INVALID_TABLE_ADDR (~0UL)
- if (efi_enabled(EFI_CONFIG_TABLES)) {
- /*
- * According to the DMTF SMBIOS reference spec v3.0.0, it is
- * allowed to define both the 64-bit entry point (smbios3) and
- * the 32-bit entry point (smbios), in which case they should
- * either both point to the same SMBIOS structure table, or the
- * table pointed to by the 64-bit entry point should contain a
- * superset of the table contents pointed to by the 32-bit entry
- * point (section 5.2)
- * This implies that the 64-bit entry point should have
- * precedence if it is defined and supported by the OS. If we
- * have the 64-bit entry point, but fail to decode it, fall
- * back to the legacy one (if available)
- */
- if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
- p = dmi_early_remap(efi.smbios3, 32);
- if (p == NULL)
- goto error;
- memcpy_fromio(buf, p, 32);
- dmi_early_unmap(p, 32);
-
- if (!dmi_smbios3_present(buf)) {
- dmi_available = 1;
- return;
- }
- }
- if (efi.smbios == EFI_INVALID_TABLE_ADDR)
- goto error;
-
- /* This is called as a core_initcall() because it isn't
- * needed during early boot. This also means we can
- * iounmap the space when we're done with it.
- */
- p = dmi_early_remap(efi.smbios, 32);
+ if (smbios3 != INVALID_TABLE_ADDR) {
+ p = dmi_early_remap(smbios3, 32);
if (p == NULL)
- goto error;
+ return -1;
memcpy_fromio(buf, p, 32);
dmi_early_unmap(p, 32);
- if (!dmi_present(buf)) {
+ if (!dmi_smbios3_present(buf)) {
dmi_available = 1;
- return;
+ return 0;
}
+ }
+
+ if (smbios == INVALID_TABLE_ADDR)
+ return -1;
+
+ /*
+ * This is called as a core_initcall() because it isn't
+ * needed during early boot. This also means we can
+ * iounmap the space when we're done with it.
+ */
+ p = dmi_early_remap(smbios, 32);
+ if (p == NULL)
+ return -1;
+ memcpy_fromio(buf, p, 32);
+ dmi_early_unmap(p, 32);
+
+ if (!dmi_present(buf)) {
+ dmi_available = 1;
+ return 0;
+ }
+ return -1;
+}
+
+static void __init dmi_scan_machine(void)
+{
+ char __iomem *p, *q;
+ char buf[32];
+
+#ifdef CONFIG_FDT_FW_INTERFACE
+ if (dmi_sacn_smbios(fdt_fwtbl.smbios3, fdt_fwtbl.smbios))
+ goto error;
+#endif
+ if (efi_enabled(EFI_CONFIG_TABLES)) {
+ if (dmi_sacn_smbios(efi.smbios3, efi.smbios))
+ goto error;
} else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, 0x10000);
if (p == NULL)
diff --git a/drivers/firmware/ffi.c b/drivers/firmware/ffi.c
new file mode 100644
index 000000000000..83c7abf22220
--- /dev/null
+++ b/drivers/firmware/ffi.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kobject.h>
+#include <linux/ffi.h>
+#include <linux/of_fdt.h>
+#include <linux/libfdt.h>
+
+struct fdt_fwtable __read_mostly fdt_fwtbl = {
+ .acpi = FDT_INVALID_FWTBL_ADDR,
+ .acpi20 = FDT_INVALID_FWTBL_ADDR,
+ .smbios = FDT_INVALID_FWTBL_ADDR,
+ .smbios3 = FDT_INVALID_FWTBL_ADDR,
+};
+EXPORT_SYMBOL(fdt_fwtbl);
+
+void __init of_fdt_fwtbl(void)
+{
+ int cfgtbl, len;
+ fdt64_t *prop;
+
+ cfgtbl = fdt_path_offset(initial_boot_params, "/cfgtables");
+ if (cfgtbl < 0) {
+ pr_info("cfgtables not found.\n");
+ return;
+ }
+ prop = fdt_getprop_w(initial_boot_params, cfgtbl, "smbios_phy_ptr", &len);
+ if (!prop || len != sizeof(u64))
+ pr_info("smbios_phy_ptr not found.\n");
+ else
+ fdt_fwtbl.smbios = fdt64_to_cpu(*prop);
+
+ prop = fdt_getprop_w(initial_boot_params, cfgtbl, "smbios3_phy_ptr", &len);
+ if (!prop || len != sizeof(u64))
+ pr_info("smbios3_phy_ptr not found.\n");
+ else
+ fdt_fwtbl.smbios3 = fdt64_to_cpu(*prop);
+
+ prop = fdt_getprop_w(initial_boot_params, cfgtbl, "acpi_phy_ptr", &len);
+ if (!prop || len != sizeof(u64))
+ pr_info("acpi_phy_ptr not found.\n");
+ else
+ fdt_fwtbl.acpi = fdt64_to_cpu(*prop);
+
+ prop = fdt_getprop_w(initial_boot_params, cfgtbl, "acpi20_phy_ptr", &len);
+ if (!prop || len != sizeof(u64))
+ pr_info("acpi20_phy_ptr not found.\n");
+ else
+ fdt_fwtbl.acpi20 = fdt64_to_cpu(*prop);
+}
+
+void __init fdt_fwtbl_init(void)
+{
+ of_fdt_fwtbl();
+}
diff --git a/include/linux/ffi.h b/include/linux/ffi.h
new file mode 100644
index 000000000000..ffb50810a01e
--- /dev/null
+++ b/include/linux/ffi.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _LINUX_FDT_FW_H
+#define _LINUX_FDT_FW_H
+
+#define FDT_INVALID_FWTBL_ADDR (~0UL)
+extern struct fdt_fwtable {
+ unsigned long acpi;
+ unsigned long acpi20;
+ unsigned long smbios;
+ unsigned long smbios3;
+ unsigned long flags;
+} fdt_fwtbl;
+
+#endif
--
2.20.1
