[PATCH v12 00/10] efi/firmware/platform-x86: Add EFI embedded fw support

[PATCH v12 00/10] efi/firmware/platform-x86: Add EFI embedded fw support

[Hans de Goede]

Hi All,

Here is v12 of my patch-set to add support for EFI embedded fw to the
kernel.

This version addresses Luis' review remarks for the test_firmware stuff
and addresses some of Andy Lutomirski's remarks (while for some others
I've explained why I've done things a certain way).

It would be nice if we could at least get patches 1 and 2 merged for
5.6 (assuming Andy is ok with them now), then we can get the rest merged
once 5.6-rc1 is out.

As mentioned in the v11 cover letter, I've based this version on Ard's
efi/next branch to avoid conflict with some changes already there.

Regards,

Hans

---
Changes in v12:
- Use memcmp to check the prefix in efi_check_for_embedded_firmwares()
- Move the vmalloc (vmemdup) for the firmware copy owned by the firmare
  subsys from efi_get_embedded_fw() to firmware_fallback_platform(), so
  that it is is in the same subsys as the vfree which eventually frees it.
- Use local / private firmware variable for the test instead of the
  global test_firmware variable and drop the mutex lock + unlock needed
  for accessing the global test_firmware variable

Changes in v11:
- Rebase on top of Ardb's efi/next
- Drop a couple of empty lines which snuck into:
  "test_firmware: add support for firmware_request_platform"

Changes in v10:
- Rebase on top of 5.5-rc1

Changes in v9:
- Add 2 new patches adding selftests
- At least touchscreen_dmi.c uses the same dmi_table for its own private
  data and the fw_desc structs, putting the fw_desc struct first in the
  data driver_data points to so that the dmi_table can be shared with
  efi_check_for_embedded_firmwares(). But not all entries there have
  embedded-fw so in some cases the fw_desc is empty (zero-ed out).
  This can lead to a possible crash because fw_desc->length now is
  less then 8, so if the segment size is close enough to a multiple of the
  page_size, then the memcmp to check the prefix my segfault. Crashing the
  machine. v9 checks for and skips these empty fw_desc entries avoiding this.
- Add static inline wrapper for firmware_request_platform() to firmware.h,
  for when CONFIG_FW_LOADER is not set

Changes in v8:
- Add pr_warn if there are mode then EFI_DEBUGFS_MAX_BLOBS boot service segments
- Document how the EFI debugfs boot_service_code? files can be used to check for
  embedded firmware
- Properly deal with the case of an EFI segment being smaller then the fw we
  are looking for
- Log a warning when efi_get_embedded_fw get called while we did not (yet)
  check for embedded firmwares
- Only build fallback_platform.c if CONFIG_EFI_EMBEDDED_FIRMWARE is defined,
  otherwise make firmware_fallback_platform() a static inline stub

Changes in v7:
- Split drivers/firmware/efi and drivers/base/firmware_loader changes into
  2 patches
- Use new, standalone, lib/crypto/sha256.c code
- Address kdoc comments from Randy Dunlap
- Add new FW_OPT_FALLBACK_PLATFORM flag and firmware_request_platform()
  _request_firmware() wrapper, as requested by Luis R. Rodriguez
- Stop using "efi-embedded-firmware" device-property, now that drivers need to
  use the new firmware_request_platform() to enable fallback to a device fw
  copy embedded in the platform's main firmware, we no longer need a property
  on the device to trigger this behavior
- Use security_kernel_load_data instead of calling
  security_kernel_read_file with a NULL file pointer argument
- Move the docs to Documentation/driver-api/firmware/fallback-mechanisms.rst
- Document the new firmware_request_platform() function in
  Documentation/driver-api/firmware/request_firmware.rst
- Add 2 new patches for the silead and chipone-icn8505 touchscreen drivers
  to use the new firmware_request_platform() method
- Rebased on top of 5.4-rc1

Changes in v6:
-Rework code to remove casts from if (prefix == mem) comparison
-Use SHA256 hashes instead of crc32 sums
-Add new READING_FIRMWARE_EFI_EMBEDDED read_file_id and use it
-Call security_kernel_read_file(NULL, READING_FIRMWARE_EFI_EMBEDDED)
 to check if this is allowed before looking at EFI embedded fw
-Document why we are not using the PI Firmware Volume protocol

Changes in v5:
-Rename the EFI_BOOT_SERVICES flag to EFI_PRESERVE_BS_REGIONS

Changes in v4:
-Drop note in docs about EFI_FIRMWARE_VOLUME_PROTOCOL, it is not part of
 UEFI proper, so the EFI maintainers don't want us referring people to it
-Use new EFI_BOOT_SERVICES flag
-Put the new fw_get_efi_embedded_fw() function in its own fallback_efi.c
 file which only gets built when EFI_EMBEDDED_FIRMWARE is selected
-Define an empty stub for fw_get_efi_embedded_fw() in fallback.h hwen
 EFI_EMBEDDED_FIRMWARE is not selected, to avoid the need for #ifdefs
 in firmware_loader/main.c
-Properly call security_kernel_post_read_file() on the firmware returned
 by efi_get_embedded_fw() to make sure that we are allowed to use it

Changes in v2:
-Rebased on driver-core/driver-core-next
-Add documentation describing the EFI embedded firmware mechanism to:
 Documentation/driver-api/firmware/request_firmware.rst
-Add a new EFI_EMBEDDED_FIRMWARE Kconfig bool and only build the embedded
 fw support if this is set. This is an invisible option which should be
 selected by drivers which need this
-Remove the efi_embedded_fw_desc and dmi_system_id-s for known devices
 from the efi-embedded-fw code, instead drivers using this are expected to
 export a dmi_system_id array, with each entries' driver_data pointing to a
 efi_embedded_fw_desc struct and register this with the efi-embedded-fw code
-Use kmemdup to make a copy instead of efi_mem_reserve()-ing the firmware,
 this avoids us messing with the EFI memmap and avoids the need to make
 changes to efi_mem_desc_lookup()
-Make the firmware-loader code only fallback to efi_get_embedded_fw() if the
 passed in device has the "efi-embedded-firmware" device-property bool set
-Skip usermodehelper fallback when "efi-embedded-firmware" device-property
 is set

[PATCH v12 01/10] efi: Export boot-services code and data as debugfs-blobs

[Hans de Goede]

Sometimes it is useful to be able to dump the efi boot-services code and
data. This commit adds these as debugfs-blobs to /sys/kernel/debug/efi,
but only if efi=debug is passed on the kernel-commandline as this requires
not freeing those memory-regions, which costs 20+ MB of RAM.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v8:
-Add pr_warn if there are mode then EFI_DEBUGFS_MAX_BLOBS boot service segments
-Document how the boot_service_code? files can be used to check for embedded
 firmware. Note since this is related to the firmware EFI embedded fw support,
 these docs are added in the 4th patch of this patch-set, not in this one.

Changes in v5:
-Rename the EFI_BOOT_SERVICES flag to EFI_PRESERVE_BS_REGIONS

Changes in v4:
-Add new EFI_BOOT_SERVICES flag and use it to determine if the boot-services
 memory segments are available (and thus if it makes sense to register the
 debugfs bits for them)

Changes in v2:
-Do not call pr_err on debugfs call failures
---
 arch/x86/platform/efi/efi.c    |  1 +
 arch/x86/platform/efi/quirks.c |  4 +++
 drivers/firmware/efi/efi.c     | 57 ++++++++++++++++++++++++++++++++++
 include/linux/efi.h            |  1 +
 4 files changed, 63 insertions(+)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 59f7f6d60cf6..51ee2e2a18d6 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -243,6 +243,7 @@ int __init efi_memblock_x86_reserve_range(void)
 	     efi.memmap.desc_version);
 
 	memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
+	set_bit(EFI_PRESERVE_BS_REGIONS, &efi.flags);
 
 	return 0;
 }
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index 46807b7606da..d5e822373450 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -409,6 +409,10 @@ void __init efi_free_boot_services(void)
 	int num_entries = 0;
 	void *new, *new_md;
 
+	/* Keep all regions for /sys/kernel/debug/efi */
+	if (efi_enabled(EFI_DBG))
+		return;
+
 	for_each_efi_memory_desc(md) {
 		unsigned long long start = md->phys_addr;
 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 621220ab3d0e..201a6799671d 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -17,6 +17,7 @@
 #include <linux/kobject.h>
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/efi.h>
 #include <linux/of.h>
@@ -325,6 +326,59 @@ static __init int efivar_ssdt_load(void)
 static inline int efivar_ssdt_load(void) { return 0; }
 #endif
 
+#ifdef CONFIG_DEBUG_FS
+
+#define EFI_DEBUGFS_MAX_BLOBS 32
+
+static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
+
+static void __init efi_debugfs_init(void)
+{
+	struct dentry *efi_debugfs;
+	efi_memory_desc_t *md;
+	char name[32];
+	int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
+	int i = 0;
+
+	efi_debugfs = debugfs_create_dir("efi", NULL);
+	if (IS_ERR_OR_NULL(efi_debugfs))
+		return;
+
+	for_each_efi_memory_desc(md) {
+		switch (md->type) {
+		case EFI_BOOT_SERVICES_CODE:
+			snprintf(name, sizeof(name), "boot_services_code%d",
+				 type_count[md->type]++);
+			break;
+		case EFI_BOOT_SERVICES_DATA:
+			snprintf(name, sizeof(name), "boot_services_data%d",
+				 type_count[md->type]++);
+			break;
+		default:
+			continue;
+		}
+
+		if (i >= EFI_DEBUGFS_MAX_BLOBS) {
+			pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
+				EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
+			break;
+		}
+
+		debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
+		debugfs_blob[i].data = memremap(md->phys_addr,
+						debugfs_blob[i].size,
+						MEMREMAP_WB);
+		if (!debugfs_blob[i].data)
+			continue;
+
+		debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
+		i++;
+	}
+}
+#else
+static inline void efi_debugfs_init(void) {}
+#endif
+
 /*
  * We register the efi subsystem with the firmware subsystem and the
  * efivars subsystem with the efi subsystem, if the system was booted with
@@ -381,6 +435,9 @@ static int __init efisubsys_init(void)
 		goto err_remove_group;
 	}
 
+	if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
+		efi_debugfs_init();
+
 	return 0;
 
 err_remove_group:
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 7efd7072cca5..a6e1a2d8511e 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1124,6 +1124,7 @@ extern int __init efi_setup_pcdp_console(char *);
 #define EFI_NX_PE_DATA		9	/* Can runtime data regions be mapped non-executable? */
 #define EFI_MEM_ATTR		10	/* Did firmware publish an EFI_MEMORY_ATTRIBUTES table? */
 #define EFI_MEM_NO_SOFT_RESERVE	11	/* Is the kernel configured to ignore soft reservations? */
+#define EFI_PRESERVE_BS_REGIONS	12	/* Are EFI boot-services memory segments available? */
 
 #ifdef CONFIG_EFI
 /*
-- 
2.24.1

[PATCH v12 02/10] efi: Add embedded peripheral firmware support

[Hans de Goede]

Just like with PCI options ROMs, which we save in the setup_efi_pci*
functions from arch/x86/boot/compressed/eboot.c, the EFI code / ROM itself
sometimes may contain data which is useful/necessary for peripheral drivers
to have access to.

Specifically the EFI code may contain an embedded copy of firmware which
needs to be (re)loaded into the peripheral. Normally such firmware would be
part of linux-firmware, but in some cases this is not feasible, for 2
reasons:

1) The firmware is customized for a specific use-case of the chipset / use
with a specific hardware model, so we cannot have a single firmware file
for the chipset. E.g. touchscreen controller firmwares are compiled
specifically for the hardware model they are used with, as they are
calibrated for a specific model digitizer.

2) Despite repeated attempts we have failed to get permission to
redistribute the firmware. This is especially a problem with customized
firmwares, these get created by the chip vendor for a specific ODM and the
copyright may partially belong with the ODM, so the chip vendor cannot
give a blanket permission to distribute these.

This commit adds support for finding peripheral firmware embedded in the
EFI code and makes the found firmware available through the new
efi_get_embedded_fw() function.

Support for loading these firmwares through the standard firmware loading
mechanism is added in a follow-up commit in this patch-series.

Note we check the EFI_BOOT_SERVICES_CODE for embedded firmware near the end
of start_kernel(), just before calling rest_init(), this is on purpose
because the typical EFI_BOOT_SERVICES_CODE memory-segment is too large for
early_memremap(), so the check must be done after mm_init(). This relies
on EFI_BOOT_SERVICES_CODE not being free-ed until efi_free_boot_services()
is called, which means that this will only work on x86 for now.

Reported-by: Dave Olsthoorn <dave@bewaar.me>
Suggested-by: Peter Jones <pjones@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v12:
- Use memcmp instead of type-punned pointer casting to compare the prefix
- Make efi_get_embedded_fw() return a const u8 * pointer to the
  efi_embedded_fw copy of the firmware instead of doing a vmemdup and
  and returning that

Changes in v9:
- At least touchscreen_dmi.c uses the same dmi_table for its own private
  data and the fw_desc structs, putting the fw_desc struct first in the
  data driver_data points to so that the dmi_table can be shared with
  efi_check_for_embedded_firmwares(). But not all entries there have
  embedded-fw so in some cases the fw_desc is empty (zero-ed out).
  This can lead to a possible crash because fw_desc->length now is
  less then 8, so if the segment size is close enough to a multiple of the
  page_size, then the memcmp to check the prefix my segfault. Crashing the
  machine. v9 checks for and skips these empty fw_desc entries avoiding this.
- Rename found_fw_list to efi_embedded_fw_list and export it for use by
  lib/test_firmware.c

Changes in v8:
- Properly deal with the (theoretical?) case of an EFI segment being
  smaller then the fw we are looking for
- Log a warning when efi_get_embedded_fw get called while we did not (yet)
  check for embedded firmwares

Changes in v7:
- Split drivers/firmware/efi and drivers/base/firmware_loader changes into
  2 patches
- Use new, standalone, lib/crypto/sha256.c code

Changes in v6:
- Rework code to remove casts from if (prefix == mem) comparison
- Use SHA256 hashes instead of crc32 sums
- Add new READING_FIRMWARE_EFI_EMBEDDED read_file_id and use it
- Call security_kernel_read_file(NULL, READING_FIRMWARE_EFI_EMBEDDED)
  to check if this is allowed before looking at EFI embedded fw
- Document why we are not using the UEFI PI Firmware Volume protocol

Changes in v5:
- Rename the EFI_BOOT_SERVICES flag to EFI_PRESERVE_BS_REGIONS

Changes in v4:
- Drop note in docs about EFI_FIRMWARE_VOLUME_PROTOCOL, it is not part of
  UEFI proper, so the EFI maintainers don't want us referring people to it
- Use new EFI_BOOT_SERVICES flag
- Put the new fw_get_efi_embedded_fw() function in its own fallback_efi.c
  file which only gets built when EFI_EMBEDDED_FIRMWARE is selected
- Define an empty stub for fw_get_efi_embedded_fw() in fallback.h hwen
  EFI_EMBEDDED_FIRMWARE is not selected, to avoid the need for #ifdefs
  in firmware_loader/main.c
- Properly call security_kernel_post_read_file() on the firmware returned
  by efi_get_embedded_fw() to make sure that we are allowed to use it

Changes in v3:
- Fix the docs using "efi-embedded-fw" as property name instead of
  "efi-embedded-firmware"

Changes in v2:
- Rebased on driver-core/driver-core-next
- Add documentation describing the EFI embedded firmware mechanism to:
  Documentation/driver-api/firmware/request_firmware.rst
- Add a new EFI_EMBEDDED_FIRMWARE Kconfig bool and only build the embedded
  fw support if this is set. This is an invisible option which should be
  selected by drivers which need this
- Remove the efi_embedded_fw_desc and dmi_system_id-s for known devices
  from the efi-embedded-fw code, instead drivers using this are expected to
  export a dmi_system_id array, with each entries' driver_data pointing to a
  efi_embedded_fw_desc struct and register this with the efi-embedded-fw code
- Use kmemdup to make a copy instead of efi_mem_reserve()-ing the firmware,
  this avoids us messing with the EFI memmap and avoids the need to make
  changes to efi_mem_desc_lookup()
- Make the firmware-loader code only fallback to efi_get_embedded_fw() if the
  passed in device has the "efi-embedded-firmware" device-property bool set
- Skip usermodehelper fallback when "efi-embedded-firmware" device-property
  is set
---
 arch/x86/platform/efi/efi.c              |   1 +
 drivers/firmware/efi/Kconfig             |   5 +
 drivers/firmware/efi/Makefile            |   1 +
 drivers/firmware/efi/embedded-firmware.c | 147 +++++++++++++++++++++++
 include/linux/efi.h                      |   6 +
 include/linux/efi_embedded_fw.h          |  41 +++++++
 6 files changed, 201 insertions(+)
 create mode 100644 drivers/firmware/efi/embedded-firmware.c
 create mode 100644 include/linux/efi_embedded_fw.h

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 51ee2e2a18d6..cc10a925d9e7 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -944,6 +944,7 @@ static void __init __efi_enter_virtual_mode(void)
 		goto err;
 	}
 
+	efi_check_for_embedded_firmwares();
 	efi_free_boot_services();
 
 	/*
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index ecc83e2f032c..613828d3f106 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -239,6 +239,11 @@ config EFI_DISABLE_PCI_DMA
 
 endmenu
 
+config EFI_EMBEDDED_FIRMWARE
+	bool
+	depends on EFI
+	select CRYPTO_LIB_SHA256
+
 config UEFI_CPER
 	bool
 
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index 554d795270d9..256d6121b2b3 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -26,6 +26,7 @@ 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
+obj-$(CONFIG_EFI_EMBEDDED_FIRMWARE)	+= embedded-firmware.o
 
 fake_map-y				+= fake_mem.o
 fake_map-$(CONFIG_X86)			+= x86_fake_mem.o
diff --git a/drivers/firmware/efi/embedded-firmware.c b/drivers/firmware/efi/embedded-firmware.c
new file mode 100644
index 000000000000..1bc9cdae2eed
--- /dev/null
+++ b/drivers/firmware/efi/embedded-firmware.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Support for extracting embedded firmware for peripherals from EFI code,
+ *
+ * Copyright (c) 2018 Hans de Goede <hdegoede@redhat.com>
+ */
+
+#include <linux/dmi.h>
+#include <linux/efi.h>
+#include <linux/efi_embedded_fw.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/vmalloc.h>
+#include <crypto/sha.h>
+
+/* Exported for use by lib/test_firmware.c only */
+LIST_HEAD(efi_embedded_fw_list);
+EXPORT_SYMBOL_GPL(efi_embedded_fw_list);
+
+static bool checked_for_fw;
+
+static const struct dmi_system_id * const embedded_fw_table[] = {
+	NULL
+};
+
+/*
+ * Note the efi_check_for_embedded_firmwares() code currently makes the
+ * following 2 assumptions. This may needs to be revisited if embedded firmware
+ * is found where this is not true:
+ * 1) The firmware is only found in EFI_BOOT_SERVICES_CODE memory segments
+ * 2) The firmware always starts at an offset which is a multiple of 8 bytes
+ */
+static int __init efi_check_md_for_embedded_firmware(
+	efi_memory_desc_t *md, const struct efi_embedded_fw_desc *desc)
+{
+	struct sha256_state sctx;
+	struct efi_embedded_fw *fw;
+	u8 sha256[32];
+	u64 i, size;
+	u8 *map;
+
+	size = md->num_pages << EFI_PAGE_SHIFT;
+	map = memremap(md->phys_addr, size, MEMREMAP_WB);
+	if (!map) {
+		pr_err("Error mapping EFI mem at %#llx\n", md->phys_addr);
+		return -ENOMEM;
+	}
+
+	for (i = 0; (i + desc->length) <= size; i += 8) {
+		if (memcmp(map + i, desc->prefix, EFI_EMBEDDED_FW_PREFIX_LEN))
+			continue;
+
+		sha256_init(&sctx);
+		sha256_update(&sctx, map + i, desc->length);
+		sha256_final(&sctx, sha256);
+		if (memcmp(sha256, desc->sha256, 32) == 0)
+			break;
+	}
+	if ((i + desc->length) > size) {
+		memunmap(map);
+		return -ENOENT;
+	}
+
+	pr_info("Found EFI embedded fw '%s'\n", desc->name);
+
+	fw = kmalloc(sizeof(*fw), GFP_KERNEL);
+	if (!fw) {
+		memunmap(map);
+		return -ENOMEM;
+	}
+
+	fw->data = kmemdup(map + i, desc->length, GFP_KERNEL);
+	memunmap(map);
+	if (!fw->data) {
+		kfree(fw);
+		return -ENOMEM;
+	}
+
+	fw->name = desc->name;
+	fw->length = desc->length;
+	list_add(&fw->list, &efi_embedded_fw_list);
+
+	return 0;
+}
+
+void __init efi_check_for_embedded_firmwares(void)
+{
+	const struct efi_embedded_fw_desc *fw_desc;
+	const struct dmi_system_id *dmi_id;
+	efi_memory_desc_t *md;
+	int i, r;
+
+	for (i = 0; embedded_fw_table[i]; i++) {
+		dmi_id = dmi_first_match(embedded_fw_table[i]);
+		if (!dmi_id)
+			continue;
+
+		fw_desc = dmi_id->driver_data;
+
+		/*
+		 * In some drivers the struct driver_data contains may contain
+		 * other driver specific data after the fw_desc struct; and
+		 * the fw_desc struct itself may be empty, skip these.
+		 */
+		if (!fw_desc->name)
+			continue;
+
+		for_each_efi_memory_desc(md) {
+			if (md->type != EFI_BOOT_SERVICES_CODE)
+				continue;
+
+			r = efi_check_md_for_embedded_firmware(md, fw_desc);
+			if (r == 0)
+				break;
+		}
+	}
+
+	checked_for_fw = true;
+}
+
+int efi_get_embedded_fw(const char *name, const u8 **data, size_t *size)
+{
+	struct efi_embedded_fw *iter, *fw = NULL;
+
+	if (!checked_for_fw) {
+		pr_warn("Warning %s called while we did not check for embedded fw\n",
+			__func__);
+		return -ENOENT;
+	}
+
+	list_for_each_entry(iter, &efi_embedded_fw_list, list) {
+		if (strcmp(name, iter->name) == 0) {
+			fw = iter;
+			break;
+		}
+	}
+
+	if (!fw)
+		return -ENOENT;
+
+	*data = fw->data;
+	*size = fw->length;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(efi_get_embedded_fw);
diff --git a/include/linux/efi.h b/include/linux/efi.h
index a6e1a2d8511e..23392b88bcc0 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1554,6 +1554,12 @@ static inline void
 efi_enable_reset_attack_mitigation(void) { }
 #endif
 
+#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE
+void efi_check_for_embedded_firmwares(void);
+#else
+static inline void efi_check_for_embedded_firmwares(void) { }
+#endif
+
 efi_status_t efi_random_get_seed(void);
 
 void efi_retrieve_tpm2_eventlog(void);
diff --git a/include/linux/efi_embedded_fw.h b/include/linux/efi_embedded_fw.h
new file mode 100644
index 000000000000..3d066c6370c6
--- /dev/null
+++ b/include/linux/efi_embedded_fw.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_EFI_EMBEDDED_FW_H
+#define _LINUX_EFI_EMBEDDED_FW_H
+
+#include <linux/list.h>
+#include <linux/mod_devicetable.h>
+
+#define EFI_EMBEDDED_FW_PREFIX_LEN		8
+
+/*
+ * This struct and efi_embedded_fw_list are private to the efi-embedded fw
+ * implementation they are in this header for use by lib/test_firmware.c only!
+ */
+struct efi_embedded_fw {
+	struct list_head list;
+	const char *name;
+	const u8 *data;
+	size_t length;
+};
+
+extern struct list_head efi_embedded_fw_list;
+
+/**
+ * struct efi_embedded_fw_desc - This struct is used by the EFI embedded-fw
+ *                               code to search for embedded firmwares.
+ *
+ * @name:   Name to register the firmware with if found
+ * @prefix: First 8 bytes of the firmware
+ * @length: Length of the firmware in bytes including prefix
+ * @sha256: SHA256 of the firmware
+ */
+struct efi_embedded_fw_desc {
+	const char *name;
+	u8 prefix[EFI_EMBEDDED_FW_PREFIX_LEN];
+	u32 length;
+	u8 sha256[32];
+};
+
+int efi_get_embedded_fw(const char *name, const u8 **dat, size_t *sz);
+
+#endif
-- 
2.24.1

[PATCH v12 03/10] firmware: Rename FW_OPT_NOFALLBACK to FW_OPT_NOFALLBACK_SYSFS

[Hans de Goede]

This is a preparation patch for adding a new platform fallback mechanism,
which will have its own enable/disable FW_OPT_xxx option.

Note this also fixes a typo in one of the re-wordwrapped comments:
enfoce -> enforce.

Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/base/firmware_loader/fallback.c | 11 ++++++-----
 drivers/base/firmware_loader/firmware.h | 16 ++++++++--------
 drivers/base/firmware_loader/main.c     |  2 +-
 3 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
index 62ee90b4db56..8704e1bae175 100644
--- a/drivers/base/firmware_loader/fallback.c
+++ b/drivers/base/firmware_loader/fallback.c
@@ -606,7 +606,7 @@ static bool fw_run_sysfs_fallback(enum fw_opt opt_flags)
 		return false;
 	}
 
-	if ((opt_flags & FW_OPT_NOFALLBACK))
+	if ((opt_flags & FW_OPT_NOFALLBACK_SYSFS))
 		return false;
 
 	/* Also permit LSMs and IMA to fail firmware sysfs fallback */
@@ -630,10 +630,11 @@ static bool fw_run_sysfs_fallback(enum fw_opt opt_flags)
  * interface. Userspace is in charge of loading the firmware through the sysfs
  * loading interface. This sysfs fallback mechanism may be disabled completely
  * on a system by setting the proc sysctl value ignore_sysfs_fallback to true.
- * If this false we check if the internal API caller set the @FW_OPT_NOFALLBACK
- * flag, if so it would also disable the fallback mechanism. A system may want
- * to enfoce the sysfs fallback mechanism at all times, it can do this by
- * setting ignore_sysfs_fallback to false and force_sysfs_fallback to true.
+ * If this is false we check if the internal API caller set the
+ * @FW_OPT_NOFALLBACK_SYSFS flag, if so it would also disable the fallback
+ * mechanism. A system may want to enforce the sysfs fallback mechanism at all
+ * times, it can do this by setting ignore_sysfs_fallback to false and
+ * force_sysfs_fallback to true.
  * Enabling force_sysfs_fallback is functionally equivalent to build a kernel
  * with CONFIG_FW_LOADER_USER_HELPER_FALLBACK.
  **/
diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h
index 7ecd590e67fe..8656e5239a80 100644
--- a/drivers/base/firmware_loader/firmware.h
+++ b/drivers/base/firmware_loader/firmware.h
@@ -27,16 +27,16 @@
  *	firmware file lookup on storage is avoided. Used for calls where the
  *	file may be too big, or where the driver takes charge of its own
  *	firmware caching mechanism.
- * @FW_OPT_NOFALLBACK: Disable the fallback mechanism. Takes precedence over
- *	&FW_OPT_UEVENT and &FW_OPT_USERHELPER.
+ * @FW_OPT_NOFALLBACK_SYSFS: Disable the sysfs fallback mechanism. Takes
+ *	precedence over &FW_OPT_UEVENT and &FW_OPT_USERHELPER.
  */
 enum fw_opt {
-	FW_OPT_UEVENT =         BIT(0),
-	FW_OPT_NOWAIT =         BIT(1),
-	FW_OPT_USERHELPER =     BIT(2),
-	FW_OPT_NO_WARN =        BIT(3),
-	FW_OPT_NOCACHE =        BIT(4),
-	FW_OPT_NOFALLBACK =     BIT(5),
+	FW_OPT_UEVENT			= BIT(0),
+	FW_OPT_NOWAIT			= BIT(1),
+	FW_OPT_USERHELPER		= BIT(2),
+	FW_OPT_NO_WARN			= BIT(3),
+	FW_OPT_NOCACHE			= BIT(4),
+	FW_OPT_NOFALLBACK_SYSFS		= BIT(5),
 };
 
 enum fw_status {
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index 249add8c5e05..57133a9dad09 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -877,7 +877,7 @@ int request_firmware_direct(const struct firmware **firmware_p,
 	__module_get(THIS_MODULE);
 	ret = _request_firmware(firmware_p, name, device, NULL, 0,
 				FW_OPT_UEVENT | FW_OPT_NO_WARN |
-				FW_OPT_NOFALLBACK);
+				FW_OPT_NOFALLBACK_SYSFS);
 	module_put(THIS_MODULE);
 	return ret;
 }
-- 
2.24.1

Re: [PATCH v12 03/10] firmware: Rename FW_OPT_NOFALLBACK to FW_OPT_NOFALLBACK_SYSFS

[Greg Kroah-Hartman]

On Wed, Jan 15, 2020 at 05:35:47PM +0100, Hans de Goede wrote:
> This is a preparation patch for adding a new platform fallback mechanism,
> which will have its own enable/disable FW_OPT_xxx option.
> 
> Note this also fixes a typo in one of the re-wordwrapped comments:
> enfoce -> enforce.
> 
> Acked-by: Luis Chamberlain <mcgrof@kernel.org>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

I've taken this in my tree for now in a quest to try to get others to
pay attention to this series...

thanks,

greg k-h

Re: [PATCH v12 03/10] firmware: Rename FW_OPT_NOFALLBACK to FW_OPT_NOFALLBACK_SYSFS

[Hans de Goede]

Hi,

On 1/24/20 9:57 AM, Greg Kroah-Hartman wrote:
> On Wed, Jan 15, 2020 at 05:35:47PM +0100, Hans de Goede wrote:
>> This is a preparation patch for adding a new platform fallback mechanism,
>> which will have its own enable/disable FW_OPT_xxx option.
>>
>> Note this also fixes a typo in one of the re-wordwrapped comments:
>> enfoce -> enforce.
>>
>> Acked-by: Luis Chamberlain <mcgrof@kernel.org>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> 
> I've taken this in my tree for now in a quest to try to get others to
> pay attention to this series...

Thank you.

As mentioned before I believe that this series is ready for merging now.

Andy Lutomirski had one last change request for v12 of the second
patch in the series, specifically to replace the loop searching for
the prefix with a memem, but the kernel does not have memmem.

Andy, are you ok with v12 as is, given that we don't have memmem ?

Assuming Andy is ok with v12 as is, then to merge this we need
to probably wait for 5.6-rc1 and then have the x86/efi folks do
an immutable branch with the first 2 patches of the series.

After that you (Greg) can merge patches 3-10 (after merging the
branch) and the platform/drivers/x86 folks can take 11 and 12
(also after merging the branch).

Regards,

Hans

Re: [PATCH v12 03/10] firmware: Rename FW_OPT_NOFALLBACK to FW_OPT_NOFALLBACK_SYSFS

[Greg Kroah-Hartman]

On Fri, Jan 24, 2020 at 10:16:48AM +0100, Hans de Goede wrote:
> Hi,
> 
> On 1/24/20 9:57 AM, Greg Kroah-Hartman wrote:
> > On Wed, Jan 15, 2020 at 05:35:47PM +0100, Hans de Goede wrote:
> > > This is a preparation patch for adding a new platform fallback mechanism,
> > > which will have its own enable/disable FW_OPT_xxx option.
> > > 
> > > Note this also fixes a typo in one of the re-wordwrapped comments:
> > > enfoce -> enforce.
> > > 
> > > Acked-by: Luis Chamberlain <mcgrof@kernel.org>
> > > Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> > 
> > I've taken this in my tree for now in a quest to try to get others to
> > pay attention to this series...
> 
> Thank you.
> 
> As mentioned before I believe that this series is ready for merging now.
> 
> Andy Lutomirski had one last change request for v12 of the second
> patch in the series, specifically to replace the loop searching for
> the prefix with a memem, but the kernel does not have memmem.
> 
> Andy, are you ok with v12 as is, given that we don't have memmem ?
> 
> Assuming Andy is ok with v12 as is, then to merge this we need
> to probably wait for 5.6-rc1 and then have the x86/efi folks do
> an immutable branch with the first 2 patches of the series.

Did this every happen?  Or do I need to dump this all into my tree?

thanks,

greg k-h

Re: [PATCH v12 03/10] firmware: Rename FW_OPT_NOFALLBACK to FW_OPT_NOFALLBACK_SYSFS

[Hans de Goede]

Hi Greg,

On 3/18/20 2:27 PM, Greg Kroah-Hartman wrote:
> On Fri, Jan 24, 2020 at 10:16:48AM +0100, Hans de Goede wrote:
>> Hi,
>>
>> On 1/24/20 9:57 AM, Greg Kroah-Hartman wrote:
>>> On Wed, Jan 15, 2020 at 05:35:47PM +0100, Hans de Goede wrote:
>>>> This is a preparation patch for adding a new platform fallback mechanism,
>>>> which will have its own enable/disable FW_OPT_xxx option.
>>>>
>>>> Note this also fixes a typo in one of the re-wordwrapped comments:
>>>> enfoce -> enforce.
>>>>
>>>> Acked-by: Luis Chamberlain <mcgrof@kernel.org>
>>>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>>>
>>> I've taken this in my tree for now in a quest to try to get others to
>>> pay attention to this series...
>>
>> Thank you.
>>
>> As mentioned before I believe that this series is ready for merging now.
>>
>> Andy Lutomirski had one last change request for v12 of the second
>> patch in the series, specifically to replace the loop searching for
>> the prefix with a memem, but the kernel does not have memmem.
>>
>> Andy, are you ok with v12 as is, given that we don't have memmem ?
>>
>> Assuming Andy is ok with v12 as is, then to merge this we need
>> to probably wait for 5.6-rc1 and then have the x86/efi folks do
>> an immutable branch with the first 2 patches of the series.
> 
> Did this every happen?  Or do I need to dump this all into my tree?

Ard has done a immutable branch with just the 2 patches:

https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git/tag/?h=stable-shared-branch-for-driver-tree

I did not see any mails about this being pulled / merged, but I just
checked and this has landed in the tip tree 10 days ago:

https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/include/linux/efi.h?h=efi/core

So if you merge the stable-shared-branch-for-driver-tree tag and then
merge patches 3-8 of this series (or rather 4-8 since you already
merged 3 IIRC) that would be great.

Regards,

Hans

Re: [PATCH v12 03/10] firmware: Rename FW_OPT_NOFALLBACK to FW_OPT_NOFALLBACK_SYSFS

[Greg Kroah-Hartman]

On Wed, Mar 18, 2020 at 02:56:23PM +0100, Hans de Goede wrote:
> Hi Greg,
> 
> On 3/18/20 2:27 PM, Greg Kroah-Hartman wrote:
> > On Fri, Jan 24, 2020 at 10:16:48AM +0100, Hans de Goede wrote:
> > > Hi,
> > > 
> > > On 1/24/20 9:57 AM, Greg Kroah-Hartman wrote:
> > > > On Wed, Jan 15, 2020 at 05:35:47PM +0100, Hans de Goede wrote:
> > > > > This is a preparation patch for adding a new platform fallback mechanism,
> > > > > which will have its own enable/disable FW_OPT_xxx option.
> > > > > 
> > > > > Note this also fixes a typo in one of the re-wordwrapped comments:
> > > > > enfoce -> enforce.
> > > > > 
> > > > > Acked-by: Luis Chamberlain <mcgrof@kernel.org>
> > > > > Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> > > > 
> > > > I've taken this in my tree for now in a quest to try to get others to
> > > > pay attention to this series...
> > > 
> > > Thank you.
> > > 
> > > As mentioned before I believe that this series is ready for merging now.
> > > 
> > > Andy Lutomirski had one last change request for v12 of the second
> > > patch in the series, specifically to replace the loop searching for
> > > the prefix with a memem, but the kernel does not have memmem.
> > > 
> > > Andy, are you ok with v12 as is, given that we don't have memmem ?
> > > 
> > > Assuming Andy is ok with v12 as is, then to merge this we need
> > > to probably wait for 5.6-rc1 and then have the x86/efi folks do
> > > an immutable branch with the first 2 patches of the series.
> > 
> > Did this every happen?  Or do I need to dump this all into my tree?
> 
> Ard has done a immutable branch with just the 2 patches:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git/tag/?h=stable-shared-branch-for-driver-tree
> 
> I did not see any mails about this being pulled / merged, but I just
> checked and this has landed in the tip tree 10 days ago:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/include/linux/efi.h?h=efi/core
> 
> So if you merge the stable-shared-branch-for-driver-tree tag and then
> merge patches 3-8 of this series (or rather 4-8 since you already
> merged 3 IIRC) that would be great.

Ok, I've merged the above branch with just the two patches, and the rest
of yours now, sorry this took so long.

greg k-h

Re: [PATCH v12 03/10] firmware: Rename FW_OPT_NOFALLBACK to FW_OPT_NOFALLBACK_SYSFS

[Hans de Goede]

Hi,

On 3/20/20 3:02 PM, Greg Kroah-Hartman wrote:
> On Wed, Mar 18, 2020 at 02:56:23PM +0100, Hans de Goede wrote:
>> Hi Greg,
>>
>> On 3/18/20 2:27 PM, Greg Kroah-Hartman wrote:
>>> On Fri, Jan 24, 2020 at 10:16:48AM +0100, Hans de Goede wrote:
>>>> Hi,
>>>>
>>>> On 1/24/20 9:57 AM, Greg Kroah-Hartman wrote:
>>>>> On Wed, Jan 15, 2020 at 05:35:47PM +0100, Hans de Goede wrote:
>>>>>> This is a preparation patch for adding a new platform fallback mechanism,
>>>>>> which will have its own enable/disable FW_OPT_xxx option.
>>>>>>
>>>>>> Note this also fixes a typo in one of the re-wordwrapped comments:
>>>>>> enfoce -> enforce.
>>>>>>
>>>>>> Acked-by: Luis Chamberlain <mcgrof@kernel.org>
>>>>>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>>>>>
>>>>> I've taken this in my tree for now in a quest to try to get others to
>>>>> pay attention to this series...
>>>>
>>>> Thank you.
>>>>
>>>> As mentioned before I believe that this series is ready for merging now.
>>>>
>>>> Andy Lutomirski had one last change request for v12 of the second
>>>> patch in the series, specifically to replace the loop searching for
>>>> the prefix with a memem, but the kernel does not have memmem.
>>>>
>>>> Andy, are you ok with v12 as is, given that we don't have memmem ?
>>>>
>>>> Assuming Andy is ok with v12 as is, then to merge this we need
>>>> to probably wait for 5.6-rc1 and then have the x86/efi folks do
>>>> an immutable branch with the first 2 patches of the series.
>>>
>>> Did this every happen?  Or do I need to dump this all into my tree?
>>
>> Ard has done a immutable branch with just the 2 patches:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git/tag/?h=stable-shared-branch-for-driver-tree
>>
>> I did not see any mails about this being pulled / merged, but I just
>> checked and this has landed in the tip tree 10 days ago:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/include/linux/efi.h?h=efi/core
>>
>> So if you merge the stable-shared-branch-for-driver-tree tag and then
>> merge patches 3-8 of this series (or rather 4-8 since you already
>> merged 3 IIRC) that would be great.
> 
> Ok, I've merged the above branch with just the two patches, and the rest
> of yours now, 

Great, thank you!

> sorry this took so long.

No problem, I'm quite happy this is queued for 5.7 now, I was
afraid it was going to slip to 5.8.

Regards,

Hans

[PATCH v12 04/10] firmware: Add new platform fallback mechanism and firmware_request_platform()

[Hans de Goede]

In some cases the platform's main firmware (e.g. the UEFI fw) may contain
an embedded copy of device firmware which needs to be (re)loaded into the
peripheral. Normally such firmware would be part of linux-firmware, but in
some cases this is not feasible, for 2 reasons:

1) The firmware is customized for a specific use-case of the chipset / use
with a specific hardware model, so we cannot have a single firmware file
for the chipset. E.g. touchscreen controller firmwares are compiled
specifically for the hardware model they are used with, as they are
calibrated for a specific model digitizer.

2) Despite repeated attempts we have failed to get permission to
redistribute the firmware. This is especially a problem with customized
firmwares, these get created by the chip vendor for a specific ODM and the
copyright may partially belong with the ODM, so the chip vendor cannot
give a blanket permission to distribute these.

This commit adds a new platform fallback mechanism to the firmware loader
which will try to lookup a device fw copy embedded in the platform's main
firmware if direct filesystem lookup fails.

Drivers which need such embedded fw copies can enable this fallback
mechanism by using the new firmware_request_platform() function.

Note that for now this is only supported on EFI platforms and even on
these platforms firmware_fallback_platform() only works if
CONFIG_EFI_EMBEDDED_FIRMWARE is enabled (this gets selected by drivers
which need this), in all other cases firmware_fallback_platform() simply
always returns -ENOENT.

Reported-by: Dave Olsthoorn <dave@bewaar.me>
Suggested-by: Peter Jones <pjones@redhat.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v12:
- Adjust firmware_fallback_platform() for efi_get_embedded_fw() now returning
  a const u8 * pointer. This means we now need to do the vmemdup (vmalloc +
  memcpy) ourselves. This is cleaner because the matching vfree is also part
  of the firmware loader code.

Changes in v9:
- Add static inline wrapper for firmware_request_platform() to firmware.h,
  for when CONFIG_FW_LOADER is not set

Changes in v8:
- Only build fallback_platform.c if CONFIG_EFI_EMBEDDED_FIRMWARE is defined,
  otherwise make firmware_fallback_platform() a static inline stub
- Add documentation to Documentation/driver-api/firmware/fallback-mechanisms.rst
  on how the boot_service_code? files exported by EFI debugfs can be used to
  check if there is an embedded firmware and to get the embedded firmware
  length and sha256sum

Changes in v7:
- Split drivers/firmware/efi and drivers/base/firmware_loader changes into
  2 patches
- Address kdoc comments from Randy Dunlap
- Add new FW_OPT_FALLBACK_PLATFORM flag and firmware_request_platform()
  _request_firmware() wrapper, as requested by Luis R. Rodriguez
- Stop using "efi-embedded-firmware" device-property, now that drivers need to
  use the new firmware_request_platform() to enable fallback to a device fw
  copy embedded in the platform's main firmware, we no longer need a property
  on the device to trigger this behavior
- Use security_kernel_load_data instead of calling
  security_kernel_read_file with a NULL file pointer argument
- Move the docs to Documentation/driver-api/firmware/fallback-mechanisms.rst
- Document the new firmware_request_platform() function in
  Documentation/driver-api/firmware/request_firmware.rst

Changes in v6:
- Rework code to remove casts from if (prefix == mem) comparison
- Use SHA256 hashes instead of crc32 sums
- Add new READING_FIRMWARE_EFI_EMBEDDED read_file_id and use it
- Call security_kernel_read_file(NULL, READING_FIRMWARE_EFI_EMBEDDED)
  to check if this is allowed before looking at EFI embedded fw
- Document why we are not using the UEFI PI Firmware Volume protocol

Changes in v5:
- Rename the EFI_BOOT_SERVICES flag to EFI_PRESERVE_BS_REGIONS

Changes in v4:
- Drop note in docs about EFI_FIRMWARE_VOLUME_PROTOCOL, it is not part of
  UEFI proper, so the EFI maintainers don't want us referring people to it
- Use new EFI_BOOT_SERVICES flag
- Put the new fw_get_efi_embedded_fw() function in its own fallback_efi.c
  file which only gets built when EFI_EMBEDDED_FIRMWARE is selected
- Define an empty stub for fw_get_efi_embedded_fw() in fallback.h hwen
  EFI_EMBEDDED_FIRMWARE is not selected, to avoid the need for #ifdefs
  in firmware_loader/main.c
- Properly call security_kernel_post_read_file() on the firmware returned
  by efi_get_embedded_fw() to make sure that we are allowed to use it

Changes in v3:
- Fix the docs using "efi-embedded-fw" as property name instead of
  "efi-embedded-firmware"

Changes in v2:
- Rebased on driver-core/driver-core-next
- Add documentation describing the EFI embedded firmware mechanism to:
  Documentation/driver-api/firmware/request_firmware.rst
- Add a new EFI_EMBEDDED_FIRMWARE Kconfig bool and only build the embedded
  fw support if this is set. This is an invisible option which should be
  selected by drivers which need this
- Remove the efi_embedded_fw_desc and dmi_system_id-s for known devices
  from the efi-embedded-fw code, instead drivers using this are expected to
  export a dmi_system_id array, with each entries' driver_data pointing to a
  efi_embedded_fw_desc struct and register this with the efi-embedded-fw code
- Use kmemdup to make a copy instead of efi_mem_reserve()-ing the firmware,
  this avoids us messing with the EFI memmap and avoids the need to make
  changes to efi_mem_desc_lookup()
- Make the firmware-loader code only fallback to efi_get_embedded_fw() if the
  passed in device has the "efi-embedded-firmware" device-property bool set
- Skip usermodehelper fallback when "efi-embedded-firmware" device-property
  is set
---
 .../firmware/fallback-mechanisms.rst          | 103 ++++++++++++++++++
 .../driver-api/firmware/lookup-order.rst      |   2 +
 .../driver-api/firmware/request_firmware.rst  |   5 +
 drivers/base/firmware_loader/Makefile         |   1 +
 drivers/base/firmware_loader/fallback.h       |  10 ++
 .../base/firmware_loader/fallback_platform.c  |  36 ++++++
 drivers/base/firmware_loader/firmware.h       |   4 +
 drivers/base/firmware_loader/main.c           |  27 +++++
 include/linux/firmware.h                      |   9 ++
 include/linux/fs.h                            |   1 +
 10 files changed, 198 insertions(+)
 create mode 100644 drivers/base/firmware_loader/fallback_platform.c

diff --git a/Documentation/driver-api/firmware/fallback-mechanisms.rst b/Documentation/driver-api/firmware/fallback-mechanisms.rst
index 8b041d0ab426..036383dad6d6 100644
--- a/Documentation/driver-api/firmware/fallback-mechanisms.rst
+++ b/Documentation/driver-api/firmware/fallback-mechanisms.rst
@@ -202,3 +202,106 @@ the following file:
 
 If you echo 0 into it means MAX_JIFFY_OFFSET will be used. The data type
 for the timeout is an int.
+
+EFI embedded firmware fallback mechanism
+========================================
+
+On some devices the system's EFI code / ROM may contain an embedded copy
+of firmware for some of the system's integrated peripheral devices and
+the peripheral's Linux device-driver needs to access this firmware.
+
+Device drivers which need such firmware can use the
+firmware_request_platform() function for this, note that this is a
+separate fallback mechanism from the other fallback mechanisms and
+this does not use the sysfs interface.
+
+A device driver which needs this can describe the firmware it needs
+using an efi_embedded_fw_desc struct:
+
+.. kernel-doc:: include/linux/efi_embedded_fw.h
+   :functions: efi_embedded_fw_desc
+
+The EFI embedded-fw code works by scanning all EFI_BOOT_SERVICES_CODE memory
+segments for an eight byte sequence matching prefix; if the prefix is found it
+then does a sha256 over length bytes and if that matches makes a copy of length
+bytes and adds that to its list with found firmwares.
+
+To avoid doing this somewhat expensive scan on all systems, dmi matching is
+used. Drivers are expected to export a dmi_system_id array, with each entries'
+driver_data pointing to an efi_embedded_fw_desc.
+
+To register this array with the efi-embedded-fw code, a driver needs to:
+
+1. Always be builtin to the kernel or store the dmi_system_id array in a
+   separate object file which always gets builtin.
+
+2. Add an extern declaration for the dmi_system_id array to
+   include/linux/efi_embedded_fw.h.
+
+3. Add the dmi_system_id array to the embedded_fw_table in
+   drivers/firmware/efi/embedded-firmware.c wrapped in a #ifdef testing that
+   the driver is being builtin.
+
+4. Add "select EFI_EMBEDDED_FIRMWARE if EFI_STUB" to its Kconfig entry.
+
+The firmware_request_platform() function will always first try to load firmware
+with the specified name directly from the disk, so the EFI embedded-fw can
+always be overridden by placing a file under /lib/firmware.
+
+Note that:
+
+1. The code scanning for EFI embedded-firmware runs near the end
+   of start_kernel(), just before calling rest_init(). For normal drivers and
+   subsystems using subsys_initcall() to register themselves this does not
+   matter. This means that code running earlier cannot use EFI
+   embedded-firmware.
+
+2. At the moment the EFI embedded-fw code assumes that firmwares always start at
+   an offset which is a multiple of 8 bytes, if this is not true for your case
+   send in a patch to fix this.
+
+3. At the moment the EFI embedded-fw code only works on x86 because other archs
+   free EFI_BOOT_SERVICES_CODE before the EFI embedded-fw code gets a chance to
+   scan it.
+
+4. The current brute-force scanning of EFI_BOOT_SERVICES_CODE is an ad-hoc
+   brute-force solution. There has been discussion to use the UEFI Platform
+   Initialization (PI) spec's Firmware Volume protocol. This has been rejected
+   because the FV Protocol relies on *internal* interfaces of the PI spec, and:
+   1. The PI spec does not define peripheral firmware at all
+   2. The internal interfaces of the PI spec do not guarantee any backward
+   compatibility. Any implementation details in FV may be subject to change,
+   and may vary system to system. Supporting the FV Protocol would be
+   difficult as it is purposely ambiguous.
+
+Example how to check for and extract embedded firmware
+------------------------------------------------------
+
+To check for, for example Silead touchscreen controller embedded firmware,
+do the following:
+
+1. Boot the system with efi=debug on the kernel commandline
+
+2. cp /sys/kernel/debug/efi/boot_services_code? to your home dir
+
+3. Open the boot_services_code? files in a hex-editor, search for the
+   magic prefix for Silead firmware: F0 00 00 00 02 00 00 00, this gives you
+   the beginning address of the firmware inside the boot_services_code? file.
+
+4. The firmware has a specific pattern, it starts with a 8 byte page-address,
+   typically F0 00 00 00 02 00 00 00 for the first page followed by 32-bit
+   word-address + 32-bit value pairs. With the word-address incrementing 4
+   bytes (1 word) for each pair until a page is complete. A complete page is
+   followed by a new page-address, followed by more word + value pairs. This
+   leads to a very distinct pattern. Scroll down until this pattern stops,
+   this gives you the end of the firmware inside the boot_services_code? file.
+
+5. "dd if=boot_services_code? of=firmware bs=1 skip=<begin-addr> count=<len>"
+   will extract the firmware for you. Inspect the firmware file in a
+   hexeditor to make sure you got the dd parameters correct.
+
+6. Copy it to /lib/firmware under the expected name to test it.
+
+7. If the extracted firmware works, you can use the found info to fill an
+   efi_embedded_fw_desc struct to describe it, run "sha256sum firmware"
+   to get the sha256sum to put in the sha256 field.
diff --git a/Documentation/driver-api/firmware/lookup-order.rst b/Documentation/driver-api/firmware/lookup-order.rst
index 88c81739683c..6064672a782e 100644
--- a/Documentation/driver-api/firmware/lookup-order.rst
+++ b/Documentation/driver-api/firmware/lookup-order.rst
@@ -12,6 +12,8 @@ a driver issues a firmware API call.
   return it immediately
 * The ''Direct filesystem lookup'' is performed next, if found we
   return it immediately
+* The ''Platform firmware fallback'' is performed next, but only when
+  firmware_request_platform() is used, if found we return it immediately
 * If no firmware has been found and the fallback mechanism was enabled
   the sysfs interface is created. After this either a kobject uevent
   is issued or the custom firmware loading is relied upon for firmware
diff --git a/Documentation/driver-api/firmware/request_firmware.rst b/Documentation/driver-api/firmware/request_firmware.rst
index f62bdcbfed5b..cd076462d235 100644
--- a/Documentation/driver-api/firmware/request_firmware.rst
+++ b/Documentation/driver-api/firmware/request_firmware.rst
@@ -25,6 +25,11 @@ firmware_request_nowarn
 .. kernel-doc:: drivers/base/firmware_loader/main.c
    :functions: firmware_request_nowarn
 
+firmware_request_platform
+-------------------------
+.. kernel-doc:: drivers/base/firmware_loader/main.c
+   :functions: firmware_request_platform
+
 request_firmware_direct
 -----------------------
 .. kernel-doc:: drivers/base/firmware_loader/main.c
diff --git a/drivers/base/firmware_loader/Makefile b/drivers/base/firmware_loader/Makefile
index 0b2dfa6259c9..e87843408fe6 100644
--- a/drivers/base/firmware_loader/Makefile
+++ b/drivers/base/firmware_loader/Makefile
@@ -5,5 +5,6 @@ obj-$(CONFIG_FW_LOADER_USER_HELPER) += fallback_table.o
 obj-$(CONFIG_FW_LOADER)	+= firmware_class.o
 firmware_class-objs := main.o
 firmware_class-$(CONFIG_FW_LOADER_USER_HELPER) += fallback.o
+firmware_class-$(CONFIG_EFI_EMBEDDED_FIRMWARE) += fallback_platform.o
 
 obj-y += builtin/
diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h
index 21063503e4ea..06f4577733a8 100644
--- a/drivers/base/firmware_loader/fallback.h
+++ b/drivers/base/firmware_loader/fallback.h
@@ -66,4 +66,14 @@ static inline void unregister_sysfs_loader(void)
 }
 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 
+#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE
+int firmware_fallback_platform(struct fw_priv *fw_priv, enum fw_opt opt_flags);
+#else
+static inline int firmware_fallback_platform(struct fw_priv *fw_priv,
+					     enum fw_opt opt_flags)
+{
+	return -ENOENT;
+}
+#endif
+
 #endif /* __FIRMWARE_FALLBACK_H */
diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c
new file mode 100644
index 000000000000..c88c745590fe
--- /dev/null
+++ b/drivers/base/firmware_loader/fallback_platform.c
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi_embedded_fw.h>
+#include <linux/property.h>
+#include <linux/security.h>
+#include <linux/vmalloc.h>
+
+#include "fallback.h"
+#include "firmware.h"
+
+int firmware_fallback_platform(struct fw_priv *fw_priv, enum fw_opt opt_flags)
+{
+	const u8 *data;
+	size_t size;
+	int rc;
+
+	if (!(opt_flags & FW_OPT_FALLBACK_PLATFORM))
+		return -ENOENT;
+
+	rc = security_kernel_load_data(LOADING_FIRMWARE_EFI_EMBEDDED);
+	if (rc)
+		return rc;
+
+	rc = efi_get_embedded_fw(fw_priv->fw_name, &data, &size);
+	if (rc)
+		return rc; /* rc == -ENOENT when the fw was not found */
+
+	fw_priv->data = vmalloc(size);
+	if (!fw_priv->data)
+		return -ENOMEM;
+
+	memcpy(fw_priv->data, data, size);
+	fw_priv->size = size;
+	fw_state_done(fw_priv);
+	return 0;
+}
diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h
index 8656e5239a80..25836a6afc9f 100644
--- a/drivers/base/firmware_loader/firmware.h
+++ b/drivers/base/firmware_loader/firmware.h
@@ -29,6 +29,9 @@
  *	firmware caching mechanism.
  * @FW_OPT_NOFALLBACK_SYSFS: Disable the sysfs fallback mechanism. Takes
  *	precedence over &FW_OPT_UEVENT and &FW_OPT_USERHELPER.
+ * @FW_OPT_FALLBACK_PLATFORM: Enable fallback to device fw copy embedded in
+ *	the platform's main firmware. If both this fallback and the sysfs
+ *      fallback are enabled, then this fallback will be tried first.
  */
 enum fw_opt {
 	FW_OPT_UEVENT			= BIT(0),
@@ -37,6 +40,7 @@ enum fw_opt {
 	FW_OPT_NO_WARN			= BIT(3),
 	FW_OPT_NOCACHE			= BIT(4),
 	FW_OPT_NOFALLBACK_SYSFS		= BIT(5),
+	FW_OPT_FALLBACK_PLATFORM	= BIT(6),
 };
 
 enum fw_status {
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index 57133a9dad09..cfdbf0010545 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -776,6 +776,9 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
 						 fw_decompress_xz);
 #endif
 
+	if (ret == -ENOENT)
+		ret = firmware_fallback_platform(fw->priv, opt_flags);
+
 	if (ret) {
 		if (!(opt_flags & FW_OPT_NO_WARN))
 			dev_warn(device,
@@ -883,6 +886,30 @@ int request_firmware_direct(const struct firmware **firmware_p,
 }
 EXPORT_SYMBOL_GPL(request_firmware_direct);
 
+/**
+ * firmware_request_platform() - request firmware with platform-fw fallback
+ * @firmware: pointer to firmware image
+ * @name: name of firmware file
+ * @device: device for which firmware is being loaded
+ *
+ * This function is similar in behaviour to request_firmware, except that if
+ * direct filesystem lookup fails, it will fallback to looking for a copy of the
+ * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
+ **/
+int firmware_request_platform(const struct firmware **firmware,
+			      const char *name, struct device *device)
+{
+	int ret;
+
+	/* Need to pin this module until return */
+	__module_get(THIS_MODULE);
+	ret = _request_firmware(firmware, name, device, NULL, 0,
+				FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
+	module_put(THIS_MODULE);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(firmware_request_platform);
+
 /**
  * firmware_request_cache() - cache firmware for suspend so resume can use it
  * @name: name of firmware file
diff --git a/include/linux/firmware.h b/include/linux/firmware.h
index 2dd566c91d44..4bbd0afd91b7 100644
--- a/include/linux/firmware.h
+++ b/include/linux/firmware.h
@@ -44,6 +44,8 @@ int request_firmware(const struct firmware **fw, const char *name,
 		     struct device *device);
 int firmware_request_nowarn(const struct firmware **fw, const char *name,
 			    struct device *device);
+int firmware_request_platform(const struct firmware **fw, const char *name,
+			      struct device *device);
 int request_firmware_nowait(
 	struct module *module, bool uevent,
 	const char *name, struct device *device, gfp_t gfp, void *context,
@@ -69,6 +71,13 @@ static inline int firmware_request_nowarn(const struct firmware **fw,
 	return -EINVAL;
 }
 
+static inline int firmware_request_platform(const struct firmware **fw,
+					    const char *name,
+					    struct device *device)
+{
+	return -EINVAL;
+}
+
 static inline int request_firmware_nowait(
 	struct module *module, bool uevent,
 	const char *name, struct device *device, gfp_t gfp, void *context,
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 98e0349adb52..4b4f11a80a2c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2964,6 +2964,7 @@ extern int do_pipe_flags(int *, int);
 	id(UNKNOWN, unknown)		\
 	id(FIRMWARE, firmware)		\
 	id(FIRMWARE_PREALLOC_BUFFER, firmware)	\
+	id(FIRMWARE_EFI_EMBEDDED, firmware)	\
 	id(MODULE, kernel-module)		\
 	id(KEXEC_IMAGE, kexec-image)		\
 	id(KEXEC_INITRAMFS, kexec-initramfs)	\
-- 
2.24.1

[PATCH v12 05/10] test_firmware: add support for firmware_request_platform

[Hans de Goede]

Add support for testing firmware_request_platform through a new
trigger_request_platform trigger.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v12:
- Use local / private firmware variable for the test instead of the
  global test_firmware variable and drop the mutex lock + unlock needed
  for accessing the global test_firmware variable

Changes in v11:
- Drop a few empty lines which were accidentally introduced

Changes in v10:
- New patch in v10 of this patch-set
---
 lib/test_firmware.c | 55 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/lib/test_firmware.c b/lib/test_firmware.c
index 251213c872b5..0c7fbcf07ac5 100644
--- a/lib/test_firmware.c
+++ b/lib/test_firmware.c
@@ -24,6 +24,7 @@
 #include <linux/delay.h>
 #include <linux/kthread.h>
 #include <linux/vmalloc.h>
+#include <linux/efi_embedded_fw.h>
 
 #define TEST_FIRMWARE_NAME	"test-firmware.bin"
 #define TEST_FIRMWARE_NUM_REQS	4
@@ -507,6 +508,57 @@ static ssize_t trigger_request_store(struct device *dev,
 }
 static DEVICE_ATTR_WO(trigger_request);
 
+#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE
+static ssize_t trigger_request_platform_store(struct device *dev,
+					      struct device_attribute *attr,
+					      const char *buf, size_t count)
+{
+	static const u8 test_data[] = {
+		0x55, 0xaa, 0x55, 0xaa, 0x01, 0x02, 0x03, 0x04,
+		0x55, 0xaa, 0x55, 0xaa, 0x05, 0x06, 0x07, 0x08,
+		0x55, 0xaa, 0x55, 0xaa, 0x10, 0x20, 0x30, 0x40,
+		0x55, 0xaa, 0x55, 0xaa, 0x50, 0x60, 0x70, 0x80
+	};
+	struct efi_embedded_fw efi_embedded_fw;
+	const struct firmware *firmware = NULL;
+	char *name;
+	int rc;
+
+	name = kstrndup(buf, count, GFP_KERNEL);
+	if (!name)
+		return -ENOSPC;
+
+	pr_info("inserting test platform fw '%s'\n", name);
+	efi_embedded_fw.name = name;
+	efi_embedded_fw.data = (void *)test_data;
+	efi_embedded_fw.length = sizeof(test_data);
+	list_add(&efi_embedded_fw.list, &efi_embedded_fw_list);
+
+	pr_info("loading '%s'\n", name);
+	rc = firmware_request_platform(&firmware, name, dev);
+	if (rc) {
+		pr_info("load of '%s' failed: %d\n", name, rc);
+		goto out;
+	}
+	if (firmware->size != sizeof(test_data) ||
+	    memcmp(firmware->data, test_data, sizeof(test_data)) != 0) {
+		pr_info("firmware contents mismatch for '%s'\n", name);
+		rc = -EINVAL;
+		goto out;
+	}
+	pr_info("loaded: %zu\n", firmware->size);
+	rc = count;
+
+out:
+	release_firmware(firmware);
+	list_del(&efi_embedded_fw.list);
+	kfree(name);
+
+	return rc;
+}
+static DEVICE_ATTR_WO(trigger_request_platform);
+#endif
+
 static DECLARE_COMPLETION(async_fw_done);
 
 static void trigger_async_request_cb(const struct firmware *fw, void *context)
@@ -903,6 +955,9 @@ static struct attribute *test_dev_attrs[] = {
 	TEST_FW_DEV_ATTR(trigger_request),
 	TEST_FW_DEV_ATTR(trigger_async_request),
 	TEST_FW_DEV_ATTR(trigger_custom_fallback),
+#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE
+	TEST_FW_DEV_ATTR(trigger_request_platform),
+#endif
 
 	/* These use the config and can use the test_result */
 	TEST_FW_DEV_ATTR(trigger_batched_requests),
-- 
2.24.1

Re: [PATCH v12 05/10] test_firmware: add support for firmware_request_platform

[Luis Chamberlain]

On Wed, Jan 15, 2020 at 05:35:49PM +0100, Hans de Goede wrote:
> Add support for testing firmware_request_platform through a new
> trigger_request_platform trigger.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Acked-by: Luis Chamberlain <mcgrof@kernel.org>

  Luis

[PATCH v12 06/10] selftests: firmware: Add firmware_request_platform tests

[Hans de Goede]

Add tests cases for checking the new firmware_request_platform api.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 .../selftests/firmware/fw_filesystem.sh       | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/tools/testing/selftests/firmware/fw_filesystem.sh b/tools/testing/selftests/firmware/fw_filesystem.sh
index 56894477c8bd..fcc281373b4d 100755
--- a/tools/testing/selftests/firmware/fw_filesystem.sh
+++ b/tools/testing/selftests/firmware/fw_filesystem.sh
@@ -86,6 +86,29 @@ else
 	fi
 fi
 
+# Try platform (EFI embedded fw) loading too
+if [ ! -e "$DIR"/trigger_request_platform ]; then
+	echo "$0: firmware loading: platform trigger not present, ignoring test" >&2
+else
+	if printf '\000' >"$DIR"/trigger_request_platform 2> /dev/null; then
+		echo "$0: empty filename should not succeed (platform)" >&2
+		exit 1
+	fi
+
+	# Note we echo a non-existing name, since files on the file-system
+	# are preferred over firmware embedded inside the platform's firmware
+	# The test adds a fake entry with the requested name to the platform's
+	# fw list, so the name does not matter as long as it does not exist
+	if ! echo -n "nope-$NAME" >"$DIR"/trigger_request_platform ; then
+		echo "$0: could not trigger request platform" >&2
+		exit 1
+	fi
+
+	# The test verifies itself that the loaded firmware contents matches
+	# the contents for the fake platform fw entry it added.
+	echo "$0: platform loading works"
+fi
+
 ### Batched requests tests
 test_config_present()
 {
-- 
2.24.1

Re: [PATCH v12 06/10] selftests: firmware: Add firmware_request_platform tests

[Luis Chamberlain]

On Wed, Jan 15, 2020 at 05:35:50PM +0100, Hans de Goede wrote:
> Add tests cases for checking the new firmware_request_platform api.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Acked-by: Luis Chamberlain <mcgrof@kernel.org>

  Luis

[PATCH v12 07/10] Input: silead - Switch to firmware_request_platform for retreiving the fw

[Hans de Goede]

Unfortunately sofar we have been unable to get permission to redistribute
Silead touchscreen firmwares in linux-firmware. This means that people
need to find and install the firmware themselves before the touchscreen
will work

Some UEFI/x86 tablets with a Silead touchscreen have a copy of the fw
embedded in their UEFI boot-services code.

This commit makes the silead driver use the new firmware_request_platform
function, which will fallback to looking for such an embedded copy when
direct filesystem lookup fails. This will make the touchscreen work OOTB
on devices where there is a fw copy embedded in the UEFI code.

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/input/touchscreen/silead.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/touchscreen/silead.c b/drivers/input/touchscreen/silead.c
index ad8b6a2bfd36..8fa2f3b7cfd8 100644
--- a/drivers/input/touchscreen/silead.c
+++ b/drivers/input/touchscreen/silead.c
@@ -288,7 +288,7 @@ static int silead_ts_load_fw(struct i2c_client *client)
 
 	dev_dbg(dev, "Firmware file name: %s", data->fw_name);
 
-	error = request_firmware(&fw, data->fw_name, dev);
+	error = firmware_request_platform(&fw, data->fw_name, dev);
 	if (error) {
 		dev_err(dev, "Firmware request error %d\n", error);
 		return error;
-- 
2.24.1

[PATCH v12 08/10] Input: icn8505 - Switch to firmware_request_platform for retreiving the fw

[Hans de Goede]

Unfortunately sofar we have been unable to get permission to redistribute
icn8505 touchscreen firmwares in linux-firmware. This means that people
need to find and install the firmware themselves before the touchscreen
will work

Some UEFI/x86 tablets with an icn8505 touchscreen have a copy of the fw
embedded in their UEFI boot-services code.

This commit makes the icn8505 driver use the new firmware_request_platform
function, which will fallback to looking for such an embedded copy when
direct filesystem lookup fails. This will make the touchscreen work OOTB
on devices where there is a fw copy embedded in the UEFI code.

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/input/touchscreen/chipone_icn8505.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/touchscreen/chipone_icn8505.c b/drivers/input/touchscreen/chipone_icn8505.c
index c768186ce856..f9ca5502ac8c 100644
--- a/drivers/input/touchscreen/chipone_icn8505.c
+++ b/drivers/input/touchscreen/chipone_icn8505.c
@@ -288,7 +288,7 @@ static int icn8505_upload_fw(struct icn8505_data *icn8505)
 	 * we may need it at resume. Having loaded it once will make the
 	 * firmware class code cache it at suspend/resume.
 	 */
-	error = request_firmware(&fw, icn8505->firmware_name, dev);
+	error = firmware_request_platform(&fw, icn8505->firmware_name, dev);
 	if (error) {
 		dev_err(dev, "Firmware request error %d\n", error);
 		return error;
-- 
2.24.1

[PATCH v12 09/10] platform/x86: touchscreen_dmi: Add EFI embedded firmware info support

[Hans de Goede]

Sofar we have been unable to get permission from the vendors to put the
firmware for touchscreens listed in touchscreen_dmi in linux-firmware.

Some of the tablets with such a touchscreen have a touchscreen driver, and
thus a copy of the firmware, as part of their EFI code.

This commit adds the necessary info for the new EFI embedded-firmware code
to extract these firmwares, making the touchscreen work OOTB without the
user needing to manually add the firmware.

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v7:
- Remove adding of PROPERTY_ENTRY_BOOL("efi-embedded-firmware"), to touchscreen
  props, as this is no longer necessary

Changes in v6:
- Switch from crc sums to SHA256 hashes for the firmware hashes
---
 drivers/firmware/efi/embedded-firmware.c |  3 ++
 drivers/platform/x86/Kconfig             |  1 +
 drivers/platform/x86/touchscreen_dmi.c   | 41 +++++++++++++++++++++++-
 include/linux/efi_embedded_fw.h          |  2 ++
 4 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/embedded-firmware.c b/drivers/firmware/efi/embedded-firmware.c
index 1bc9cdae2eed..a1b199de9006 100644
--- a/drivers/firmware/efi/embedded-firmware.c
+++ b/drivers/firmware/efi/embedded-firmware.c
@@ -21,6 +21,9 @@ EXPORT_SYMBOL_GPL(efi_embedded_fw_list);
 static bool checked_for_fw;
 
 static const struct dmi_system_id * const embedded_fw_table[] = {
+#ifdef CONFIG_TOUCHSCREEN_DMI
+	touchscreen_dmi_table,
+#endif
 	NULL
 };
 
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 27d5b40fb717..a65f4ffb289a 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -1253,6 +1253,7 @@ config INTEL_TURBO_MAX_3
 config TOUCHSCREEN_DMI
 	bool "DMI based touchscreen configuration info"
 	depends on ACPI && DMI && I2C=y && TOUCHSCREEN_SILEAD
+	select EFI_EMBEDDED_FIRMWARE if EFI
 	---help---
 	  Certain ACPI based tablets with e.g. Silead or Chipone touchscreens
 	  do not have enough data in ACPI tables for the touchscreen driver to
diff --git a/drivers/platform/x86/touchscreen_dmi.c b/drivers/platform/x86/touchscreen_dmi.c
index 72205771d03d..4449e4c0b26b 100644
--- a/drivers/platform/x86/touchscreen_dmi.c
+++ b/drivers/platform/x86/touchscreen_dmi.c
@@ -11,12 +11,15 @@
 #include <linux/acpi.h>
 #include <linux/device.h>
 #include <linux/dmi.h>
+#include <linux/efi_embedded_fw.h>
 #include <linux/i2c.h>
 #include <linux/notifier.h>
 #include <linux/property.h>
 #include <linux/string.h>
 
 struct ts_dmi_data {
+	/* The EFI embedded-fw code expects this to be the first member! */
+	struct efi_embedded_fw_desc embedded_fw;
 	const char *acpi_name;
 	const struct property_entry *properties;
 };
@@ -64,6 +67,15 @@ static const struct property_entry chuwi_hi8_pro_props[] = {
 };
 
 static const struct ts_dmi_data chuwi_hi8_pro_data = {
+	.embedded_fw = {
+		.name	= "silead/gsl3680-chuwi-hi8-pro.fw",
+		.prefix = { 0xf0, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00 },
+		.length	= 39864,
+		.sha256	= { 0xc0, 0x88, 0xc5, 0xef, 0xd1, 0x70, 0x77, 0x59,
+			    0x4e, 0xe9, 0xc4, 0xd8, 0x2e, 0xcd, 0xbf, 0x95,
+			    0x32, 0xd9, 0x03, 0x28, 0x0d, 0x48, 0x9f, 0x92,
+			    0x35, 0x37, 0xf6, 0x8b, 0x2a, 0xe4, 0x73, 0xff },
+	},
 	.acpi_name	= "MSSL1680:00",
 	.properties	= chuwi_hi8_pro_props,
 };
@@ -181,6 +193,15 @@ static const struct property_entry cube_iwork8_air_props[] = {
 };
 
 static const struct ts_dmi_data cube_iwork8_air_data = {
+	.embedded_fw = {
+		.name	= "silead/gsl3670-cube-iwork8-air.fw",
+		.prefix = { 0xf0, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00 },
+		.length	= 38808,
+		.sha256	= { 0xff, 0x62, 0x2d, 0xd1, 0x8a, 0x78, 0x04, 0x7b,
+			    0x33, 0x06, 0xb0, 0x4f, 0x7f, 0x02, 0x08, 0x9c,
+			    0x96, 0xd4, 0x9f, 0x04, 0xe1, 0x47, 0x25, 0x25,
+			    0x60, 0x77, 0x41, 0x33, 0xeb, 0x12, 0x82, 0xfc },
+	},
 	.acpi_name	= "MSSL1680:00",
 	.properties	= cube_iwork8_air_props,
 };
@@ -390,6 +411,15 @@ static const struct property_entry onda_v80_plus_v3_props[] = {
 };
 
 static const struct ts_dmi_data onda_v80_plus_v3_data = {
+	.embedded_fw = {
+		.name	= "silead/gsl3676-onda-v80-plus-v3.fw",
+		.prefix = { 0xf0, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00 },
+		.length	= 37224,
+		.sha256	= { 0x8f, 0xbd, 0x8f, 0x0c, 0x6b, 0xba, 0x5b, 0xf5,
+			    0xa3, 0xc7, 0xa3, 0xc0, 0x4f, 0xcd, 0xdf, 0x32,
+			    0xcc, 0xe4, 0x70, 0xd6, 0x46, 0x9c, 0xd7, 0xa7,
+			    0x4b, 0x82, 0x3f, 0xab, 0xc7, 0x90, 0xea, 0x23 },
+	},
 	.acpi_name	= "MSSL1680:00",
 	.properties	= onda_v80_plus_v3_props,
 };
@@ -456,6 +486,15 @@ static const struct property_entry pipo_w2s_props[] = {
 };
 
 static const struct ts_dmi_data pipo_w2s_data = {
+	.embedded_fw = {
+		.name	= "silead/gsl1680-pipo-w2s.fw",
+		.prefix = { 0xf0, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00 },
+		.length	= 39072,
+		.sha256	= { 0xd0, 0x58, 0xc4, 0x7d, 0x55, 0x2d, 0x62, 0x18,
+			    0xd1, 0x6a, 0x71, 0x73, 0x0b, 0x3f, 0xbe, 0x60,
+			    0xbb, 0x45, 0x8c, 0x52, 0x27, 0xb7, 0x18, 0xf4,
+			    0x31, 0x00, 0x6a, 0x49, 0x76, 0xd8, 0x7c, 0xd3 },
+	},
 	.acpi_name	= "MSSL1680:00",
 	.properties	= pipo_w2s_props,
 };
@@ -642,7 +681,7 @@ static const struct ts_dmi_data trekstor_surftab_wintron70_data = {
 };
 
 /* NOTE: Please keep this table sorted alphabetically */
-static const struct dmi_system_id touchscreen_dmi_table[] = {
+const struct dmi_system_id touchscreen_dmi_table[] = {
 	{
 		/* Chuwi Hi8 */
 		.driver_data = (void *)&chuwi_hi8_data,
diff --git a/include/linux/efi_embedded_fw.h b/include/linux/efi_embedded_fw.h
index 3d066c6370c6..57eac5241303 100644
--- a/include/linux/efi_embedded_fw.h
+++ b/include/linux/efi_embedded_fw.h
@@ -36,6 +36,8 @@ struct efi_embedded_fw_desc {
 	u8 sha256[32];
 };
 
+extern const struct dmi_system_id touchscreen_dmi_table[];
+
 int efi_get_embedded_fw(const char *name, const u8 **dat, size_t *sz);
 
 #endif
-- 
2.24.1

[PATCH v12 10/10] platform/x86: touchscreen_dmi: Add info for the Chuwi Vi8 Plus tablet

[Hans de Goede]

Add touchscreen info for the Chuwi Vi8 Plus tablet. This tablet uses a
Chipone ICN8505 touchscreen controller, with the firmware used by the
touchscreen embedded in the EFI firmware.

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v7:
- Remove PROPERTY_ENTRY_BOOL("efi-embedded-firmware") properties entry,
  as this is no longer necessary

Changes in v6:
- Switch from crc sums to SHA256 hashes for the firmware hash
---
 drivers/platform/x86/touchscreen_dmi.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/platform/x86/touchscreen_dmi.c b/drivers/platform/x86/touchscreen_dmi.c
index 4449e4c0b26b..4a09b479cda5 100644
--- a/drivers/platform/x86/touchscreen_dmi.c
+++ b/drivers/platform/x86/touchscreen_dmi.c
@@ -132,6 +132,18 @@ static const struct ts_dmi_data chuwi_vi8_data = {
 	.properties     = chuwi_vi8_props,
 };
 
+static const struct ts_dmi_data chuwi_vi8_plus_data = {
+	.embedded_fw = {
+		.name	= "chipone/icn8505-HAMP0002.fw",
+		.prefix = { 0xb0, 0x07, 0x00, 0x00, 0xe4, 0x07, 0x00, 0x00 },
+		.length	= 35012,
+		.sha256	= { 0x93, 0xe5, 0x49, 0xe0, 0xb6, 0xa2, 0xb4, 0xb3,
+			    0x88, 0x96, 0x34, 0x97, 0x5e, 0xa8, 0x13, 0x78,
+			    0x72, 0x98, 0xb8, 0x29, 0xeb, 0x5c, 0xa7, 0xf1,
+			    0x25, 0x13, 0x43, 0xf4, 0x30, 0x7c, 0xfc, 0x7c },
+	},
+};
+
 static const struct property_entry chuwi_vi10_props[] = {
 	PROPERTY_ENTRY_U32("touchscreen-min-x", 0),
 	PROPERTY_ENTRY_U32("touchscreen-min-y", 4),
@@ -743,6 +755,15 @@ const struct dmi_system_id touchscreen_dmi_table[] = {
 			DMI_MATCH(DMI_BIOS_VERSION, "CHUWI.D86JLBNR"),
 		},
 	},
+	{
+		/* Chuwi Vi8 Plus (CWI519) */
+		.driver_data = (void *)&chuwi_vi8_plus_data,
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Hampoo"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "D2D3_Vi8A1"),
+			DMI_MATCH(DMI_BOARD_NAME, "Cherry Trail CR"),
+		},
+	},
 	{
 		/* Chuwi Vi10 (CWI505) */
 		.driver_data = (void *)&chuwi_vi10_data,
@@ -1137,6 +1158,9 @@ static int __init ts_dmi_init(void)
 		return 0; /* Not an error */
 
 	ts_data = dmi_id->driver_data;
+	/* Some dmi table entries only provide an efi_embedded_fw_desc */
+	if (!ts_data->properties)
+		return 0;
 
 	error = bus_register_notifier(&i2c_bus_type, &ts_dmi_notifier);
 	if (error)
-- 
2.24.1