> -----Original Message----- > From: K, Narendra > Sent: Wednesday, July 10, 2019 11:59 AM > To: [email protected]; [email protected]; [email protected] > Cc: K, Narendra; Hayes, Stuart; Limonciello, Mario > Subject: [PATCH v1] Export Runtime Configuration Interface table to sysfs > > From: Narendra K <[email protected]> > > System firmware advertises the address of the 'Runtime Configuration Interface > table version 2 (RCI2)' via an EFI Configuration Table entry. This code > retrieves > the RCI2 table from the address and exports it to sysfs as a binary attribute > 'rci2' > under /sys/firmware/efi/tables directory. > The approach adopted is similar to the attribute 'DMI' under > /sys/firmware/dmi/tables. > > RCI2 table contains BIOS HII in XML format and is used to populate BIOS setup > page in Dell EMC OpenManage Server Administrator tool. > The BIOS setup page contains BIOS tokens which can be configured. > > Signed-off-by: Narendra K <[email protected]>
Reviewed-by: Mario Limonciello <[email protected]> > --- > Hi Ard, the review comment in the v0 version of the patch suggested that the > kconfig symbol be set to Y for X86. I made a change to the suggestion. > In the v1 version, I have set the symbol to N by default and added a note to > the > help section to make it Y for Dell EMC PowerEdge systems. If it needs to be > changed, I will resubmit the patch after changing it to implement the > suggestion. > > The patch is created on 'next' branch of efi tree. > > v0 -> v1: > - Introduced a new Kconfig symbol CONFIG_EFI_RCI2_TABLE and compile > RCI2 table support if it is set. Set the symbol to N by default. > - Removed calling 'efi_rci2_sysfs_init' from drivers/firmware/efi/efi.c and > made > it a 'late_initcall' in drivers/firmware/efi/rci2_table.c. > Removed the function declaration from include/linux/efi.h. > > RFC -> v0: > - Removed rci2 table from struct efi and defined it in rci2_table.c similar > to the > way uv_systab_phys is defined in arch/x86/platform/uv/bios_uv.c > - Removed the oem_tables array and added rci2 to common_tables array > - Removed the string 'rci2' from the common_tables array so that it is not > printed in dmesg. > - Merged function 'efi_rci2_table_init' into 'efi_rci2_sysfs_init' function > to avoid > calling early_memremap/unmap functions. > > Documentation/ABI/testing/sysfs-firmware-efi | 8 + > arch/x86/platform/efi/efi.c | 3 + > drivers/firmware/efi/Kconfig | 15 ++ > drivers/firmware/efi/Makefile | 1 + > drivers/firmware/efi/efi.c | 3 + > drivers/firmware/efi/rci2_table.c | 147 +++++++++++++++++++ > include/linux/efi.h | 9 ++ > 7 files changed, 186 insertions(+) > create mode 100644 drivers/firmware/efi/rci2_table.c > > diff --git a/Documentation/ABI/testing/sysfs-firmware-efi > b/Documentation/ABI/testing/sysfs-firmware-efi > index e794eac32a90..5e4d0b27cdfe 100644 > --- a/Documentation/ABI/testing/sysfs-firmware-efi > +++ b/Documentation/ABI/testing/sysfs-firmware-efi > @@ -28,3 +28,11 @@ Description: Displays the physical addresses of all > EFI Configuration > versions are always printed first, i.e. ACPI20 comes > before ACPI. > Users: dmidecode > + > +What: /sys/firmware/efi/tables/rci2 > +Date: July 2019 > +Contact: Narendra K <[email protected]>, [email protected] > +Description: Displays the content of the Runtime Configuration Interface > + Table version 2 on Dell EMC PowerEdge systems in binary > format > +Users: It is used by Dell EMC OpenManage Server Administrator > tool to > + populate BIOS setup page. > diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index > 6697c109c449..c202e1b07e29 100644 > --- a/arch/x86/platform/efi/efi.c > +++ b/arch/x86/platform/efi/efi.c > @@ -82,6 +82,9 @@ static const unsigned long * const efi_tables[] = { > &efi.esrt, > &efi.properties_table, > &efi.mem_attr_table, > +#ifdef CONFIG_EFI_RCI2_TABLE > + &rci2_table_phys, > +#endif > }; > > u64 efi_setup; /* efi setup_data physical address */ > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index > d4ea929e8b34..1e1e33b61713 100644 > --- a/drivers/firmware/efi/Kconfig > +++ b/drivers/firmware/efi/Kconfig > @@ -180,6 +180,21 @@ config RESET_ATTACK_MITIGATION > have been evicted, since otherwise it will trigger even on clean > reboots. > > +config EFI_RCI2_TABLE > + bool "EFI Runtime Configuration Interface Table Version 2 Support" > + depends on EFI > + default n > + help > + Displays the content of the Runtime Configuration Interface > + Table version 2 on Dell EMC PowerEdge systems as a binary > + attribute 'rci2' under /sys/firmware/efi/tables directory. > + > + RCI2 table contains BIOS HII in XML format and is used to populate > + BIOS setup page in Dell EMC OpenManage Server Administrator tool. > + The BIOS setup page contains BIOS tokens which can be configured. > + > + Say Y here for Dell EMC PowerEdge systems. > + > endmenu > > config UEFI_CPER > diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile > index > d2d0d2030620..2693f291a950 100644 > --- a/drivers/firmware/efi/Makefile > +++ b/drivers/firmware/efi/Makefile > @@ -25,6 +25,7 @@ obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += > efibc.o > obj-$(CONFIG_EFI_TEST) += test/ > obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o > obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o > +obj-$(CONFIG_EFI_RCI2_TABLE) += rci2_table.o > > arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o > obj-$(CONFIG_ARM) += $(arm-obj-y) > diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index > d082d5b2fb84..d01b05c1ee49 100644 > --- a/drivers/firmware/efi/efi.c > +++ b/drivers/firmware/efi/efi.c > @@ -463,6 +463,9 @@ static __initdata efi_config_table_type_t > common_tables[] = { > {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed}, > {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log}, > {LINUX_EFI_MEMRESERVE_TABLE_GUID, "MEMRESERVE", > &efi.mem_reserve}, > +#ifdef CONFIG_EFI_RCI2_TABLE > + {DELLEMC_EFI_RCI2_TABLE_GUID, NULL, &rci2_table_phys}, #endif > {NULL_GUID, NULL, NULL}, > }; > > diff --git a/drivers/firmware/efi/rci2_table.c > b/drivers/firmware/efi/rci2_table.c > new file mode 100644 > index 000000000000..3e290f96620a > --- /dev/null > +++ b/drivers/firmware/efi/rci2_table.c > @@ -0,0 +1,147 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Export Runtime Configuration Interface Table Version 2 (RCI2) > + * to sysfs > + * > + * Copyright (C) 2019 Dell Inc > + * by Narendra K <[email protected]> > + * > + * System firmware advertises the address of the RCI2 Table via > + * an EFI Configuration Table entry. This code retrieves the RCI2 > + * table from the address and exports it to sysfs as a binary > + * attribute 'rci2' under /sys/firmware/efi/tables directory. > + */ > + > +#include <linux/kobject.h> > +#include <linux/device.h> > +#include <linux/sysfs.h> > +#include <linux/efi.h> > +#include <linux/types.h> > +#include <linux/io.h> > + > +#define RCI_SIGNATURE "_RC_" > + > +struct rci2_table_global_hdr { > + u16 type; > + u16 resvd0; > + u16 hdr_len; > + u8 rci2_sig[4]; > + u16 resvd1; > + u32 resvd2; > + u32 resvd3; > + u8 major_rev; > + u8 minor_rev; > + u16 num_of_structs; > + u32 rci2_len; > + u16 rci2_chksum; > +} __packed; > + > +static u8 *rci2_base; > +static u32 rci2_table_len; > +unsigned long rci2_table_phys __ro_after_init = EFI_INVALID_TABLE_ADDR; > + > +static ssize_t raw_table_read(struct file *file, struct kobject *kobj, > + struct bin_attribute *attr, char *buf, > + loff_t pos, size_t count) > +{ > + memcpy(buf, attr->private + pos, count); > + return count; > +} > + > +static BIN_ATTR(rci2, S_IRUSR, raw_table_read, NULL, 0); > + > +static u16 checksum(void) > +{ > + u8 len_is_odd = rci2_table_len % 2; > + u32 chksum_len = rci2_table_len; > + u16 *base = (u16 *)rci2_base; > + u8 buf[2] = {0}; > + u32 offset = 0; > + u16 chksum = 0; > + > + if (len_is_odd) > + chksum_len -= 1; > + > + while (offset < chksum_len) { > + chksum += *base; > + offset += 2; > + base++; > + } > + > + if (len_is_odd) { > + buf[0] = *(u8 *)base; > + chksum += *(u16 *)(buf); > + } > + > + return chksum; > +} > + > +int __init efi_rci2_sysfs_init(void) > +{ > + struct kobject *tables_kobj; > + int ret = -ENOMEM; > + > + rci2_base = memremap(rci2_table_phys, > + sizeof(struct rci2_table_global_hdr), > + MEMREMAP_WB); > + if (!rci2_base) { > + pr_debug("RCI2 table init failed - could not map RCI2 table\n"); > + goto err; > + } > + > + if (strncmp(rci2_base + > + offsetof(struct rci2_table_global_hdr, rci2_sig), > + RCI_SIGNATURE, 4)) { > + pr_debug("RCI2 table init failed - incorrect signature\n"); > + ret = -ENODEV; > + goto err_unmap; > + } > + > + rci2_table_len = *(u32 *)(rci2_base + > + offsetof(struct rci2_table_global_hdr, > + rci2_len)); > + > + memunmap(rci2_base); > + > + if (!rci2_table_len) { > + pr_debug("RCI2 table init failed - incorrect table length\n"); > + goto err; > + } > + > + rci2_base = memremap(rci2_table_phys, rci2_table_len, > MEMREMAP_WB); > + if (!rci2_base) { > + pr_debug("RCI2 table - could not map RCI2 table\n"); > + goto err; > + } > + > + if (checksum() != 0) { > + pr_debug("RCI2 table - incorrect checksum\n"); > + ret = -ENODEV; > + goto err_unmap; > + } > + > + tables_kobj = kobject_create_and_add("tables", efi_kobj); > + if (!tables_kobj) { > + pr_debug("RCI2 table - tables_kobj creation failed\n"); > + goto err_unmap; > + } > + > + bin_attr_rci2.size = rci2_table_len; > + bin_attr_rci2.private = rci2_base; > + ret = sysfs_create_bin_file(tables_kobj, &bin_attr_rci2); > + if (ret != 0) { > + pr_debug("RCI2 table - rci2 sysfs bin file creation failed\n"); > + kobject_del(tables_kobj); > + kobject_put(tables_kobj); > + goto err_unmap; > + } > + > + return 0; > + > + err_unmap: > + memunmap(rci2_base); > + err: > + pr_debug("RCI2 table - sysfs initialization failed\n"); > + return ret; > +} > +late_initcall(efi_rci2_sysfs_init); > diff --git a/include/linux/efi.h b/include/linux/efi.h index > ac48db107214..b07c89b7cba2 100644 > --- a/include/linux/efi.h > +++ b/include/linux/efi.h > @@ -691,6 +691,11 @@ void efi_native_runtime_setup(void); > #define LINUX_EFI_TPM_EVENT_LOG_GUID EFI_GUID(0xb7799cb0, > 0xeca2, 0x4943, 0x96, 0x67, 0x1f, 0xae, 0x07, 0xb7, 0x47, 0xfa) > #define LINUX_EFI_MEMRESERVE_TABLE_GUID EFI_GUID(0x888eb0c6, > 0x8ede, 0x4ff5, 0xa8, 0xf0, 0x9a, 0xee, 0x5c, 0xb9, 0x77, 0xc2) > > +#ifdef CONFIG_EFI_RCI2_TABLE > +/* OEM GUIDs */ > +#define DELLEMC_EFI_RCI2_TABLE_GUID EFI_GUID(0x2d9f28a2, > 0xa886, 0x456a, 0x97, 0xa8, 0xf1, 0x1e, 0xf2, 0x4f, 0xf4, 0x55) > +#endif > + > typedef struct { > efi_guid_t guid; > u64 table; > @@ -1703,6 +1708,10 @@ struct linux_efi_tpm_eventlog { > > extern int efi_tpm_eventlog_init(void); > > +#ifdef CONFIG_EFI_RCI2_TABLE > +extern unsigned long rci2_table_phys; > +#endif > + > /* > * efi_runtime_service() function identifiers. > * "NONE" is used by efi_recover_from_page_fault() to check if the page > -- > 2.18.1 > > -- > With regards, > Narendra K
