To enable DMI functionality on platforms where the bootloader does not support EFI and the architecture does not support reserved addresses. Add a "ffitbl" device tree node to find the SMBIOS entry point and use wire up dmi_scan_machine().This feature is known as the FDT Firmware Interface (FFI). Signed-off-by: Yunhui Cui <cuiyunhui@xxxxxxxxxxxxx> --- MAINTAINERS | 6 +++ drivers/firmware/Kconfig | 11 +++++ drivers/firmware/Makefile | 1 + drivers/firmware/dmi_scan.c | 97 ++++++++++++++++++++++--------------- drivers/firmware/ffi.c | 42 ++++++++++++++++ include/linux/ffi.h | 29 +++++++++++ 6 files changed, 146 insertions(+), 40 deletions(-) create mode 100644 drivers/firmware/ffi.c create mode 100644 include/linux/ffi.h diff --git a/MAINTAINERS b/MAINTAINERS index e592f489e757..9b886ef36587 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7871,6 +7871,12 @@ 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/firmware/Kconfig b/drivers/firmware/Kconfig index b59e3041fd62..3579d9bc22ff 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -303,6 +303,17 @@ 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 + Enable this option to support the transfer of firmware information, + such as smbios tables, for bootloaders that do not support EFI, such + as coreboot. + + Say Y here if you want to transfer 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..c29ea050b5b9 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 +656,70 @@ 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]; - - 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); + #define INVALID_TABLE_ADDR (~0UL) + 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]; + + if (ffi_enabled(FFI_CONFIG_TABLES)) { + if (!dmi_sacn_smbios(ffi.smbios3, ffi.smbios)) + return; + } + + 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..d4994a22438b --- /dev/null +++ b/drivers/firmware/ffi.c @@ -0,0 +1,42 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/libfdt.h> +#include <linux/ffi.h> + +#define FFI_INVALID_TABLE_ADDR (~0UL) + +struct ffi __read_mostly ffi = { + .smbios = FFI_INVALID_TABLE_ADDR, + .smbios3 = FFI_INVALID_TABLE_ADDR, +}; + +void __init ffi_smbios_root_pointer(void) +{ + u32 ffitbl, smbios, len, ver; + u64 entry; + fdt64_t *prop; + + ffitbl = fdt_subnode_offset(initial_boot_params, 0, "ffitbl"); + smbios = fdt_subnode_offset(initial_boot_params, ffitbl, "smbios"); + prop = fdt_getprop_w(initial_boot_params, smbios, "entry", &len); + if (!prop || len != sizeof(u64)) { + pr_debug("smbios entry not found.\n"); + return; + } + entry = fdt64_to_cpu(*prop); + + prop = fdt_getprop_w(initial_boot_params, smbios, "reg", &len); + if (!prop || len != sizeof(u32)) { + pr_debug("smbios reg not found.\n"); + return; + } + ver = fdt32_to_cpu(*prop); + (ver == 3) ? (ffi.smbios3 = entry) : (ffi.smbios = entry); + set_bit(FFI_CONFIG_TABLES, &ffi.flags); + pr_debug("smbios%d entry: %llx\n", ver, entry); +} + diff --git a/include/linux/ffi.h b/include/linux/ffi.h new file mode 100644 index 000000000000..a99c2a290556 --- /dev/null +++ b/include/linux/ffi.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _LINUX_FFI_H +#define _LINUX_FFI_H + +extern struct ffi { + unsigned long smbios; /* SMBIOS table (32 bit entry point) */ + unsigned long smbios3; /* SMBIOS table (64 bit entry point) */ + unsigned long flags; + +} ffi; + +#define FFI_CONFIG_TABLES 2 /* Can we use FFI config tables? */ + +#ifdef CONFIG_FDT_FW_INTERFACE +extern void ffi_smbios_root_pointer(void); +static inline bool ffi_enabled(int feature) +{ + return test_bit(feature, &ffi.flags) != 0; +} +#else +static inline bool ffi_enabled(int feature) +{ + return false; +} +void ffi_smbios_root_pointer(void) { return; }; +#endif + +#endif /* _LINUX_FFI_H */ -- 2.20.1