| Message ID | 20220802140343.3468976-1-jrosenth@chromium.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v6] firmware: google: Implement cbmem in sysfs driver | expand |
On Tue, Aug 2, 2022 at 7:04 AM Jack Rosenthal <jrosenth@chromium.org> wrote: > > cbmem entries can be read from coreboot table > 0x31 (LB_TAG_CBMEM_ENTRY). This commit exports access to cbmem > entries in sysfs under /sys/firmware/coreboot/cbmem-*. > > Link: https://issuetracker.google.com/239604743 > Cc: Stephen Boyd <swboyd@chromium.org> > Cc: Guenter Roeck <groeck@chromium.org> > Reviewed-by: Julius Werner <jwerner@chromium.org> > Reported-by: kernel test robot <lkp@intel.com> > Tested-by: Jack Rosenthal <jrosenth@chromium.org> > Signed-off-by: Jack Rosenthal <jrosenth@chromium.org> Reviewed-by: Guenter Roeck <groeck@chromium.org> > --- > v6: Modified commit message. > .../ABI/testing/sysfs-firmware-coreboot | 17 ++ > drivers/firmware/google/Kconfig | 8 + > drivers/firmware/google/Makefile | 3 + > drivers/firmware/google/cbmem.c | 232 ++++++++++++++++++ > drivers/firmware/google/coreboot_table.h | 11 + > 5 files changed, 271 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-firmware-coreboot > create mode 100644 drivers/firmware/google/cbmem.c > > diff --git a/Documentation/ABI/testing/sysfs-firmware-coreboot b/Documentation/ABI/testing/sysfs-firmware-coreboot > new file mode 100644 > index 000000000000..2401483bb86c > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-firmware-coreboot > @@ -0,0 +1,17 @@ > +What: /sys/firmware/coreboot/ > +Date: July 2022 > +Contact: Jack Rosenthal <jrosenth@chromium.org> > +Description: > + Coreboot-based BIOS firmware provides a variety of information > + in CBMEM. Each CBMEM entry can be found via Coreboot tables. > + For each CBMEM entry, the following are exposed: > + > + ======= ======================================================= > + address A hexidecimal value of the memory address the data for > + the entry begins at. > + size The size of the data stored. > + id The id corresponding to the entry. A list of ids known > + to coreboot can be found in the coreboot source tree at > + ``src/commonlib/bsd/include/commonlib/bsd/cbmem_id.h`` > + mem A file exposing the raw memory for the entry. > + ======= ======================================================= > diff --git a/drivers/firmware/google/Kconfig b/drivers/firmware/google/Kconfig > index 983e07dc022e..bf8316d1cb31 100644 > --- a/drivers/firmware/google/Kconfig > +++ b/drivers/firmware/google/Kconfig > @@ -19,6 +19,14 @@ config GOOGLE_SMI > driver provides an interface for reading and writing NVRAM > variables. > > +config GOOGLE_CBMEM > + tristate "CBMEM entries in sysfs" > + depends on GOOGLE_COREBOOT_TABLE > + help > + This option enables the kernel to search for Coreboot CBMEM > + entries, and expose the memory for each entry in sysfs under > + /sys/firmware/coreboot. > + > config GOOGLE_COREBOOT_TABLE > tristate "Coreboot Table Access" > depends on HAS_IOMEM && (ACPI || OF) > diff --git a/drivers/firmware/google/Makefile b/drivers/firmware/google/Makefile > index d17caded5d88..8151e323cc43 100644 > --- a/drivers/firmware/google/Makefile > +++ b/drivers/firmware/google/Makefile > @@ -7,5 +7,8 @@ obj-$(CONFIG_GOOGLE_MEMCONSOLE) += memconsole.o > obj-$(CONFIG_GOOGLE_MEMCONSOLE_COREBOOT) += memconsole-coreboot.o > obj-$(CONFIG_GOOGLE_MEMCONSOLE_X86_LEGACY) += memconsole-x86-legacy.o > > +# Must come after coreboot_table.o, as this driver depends on that bus type. > +obj-$(CONFIG_GOOGLE_CBMEM) += cbmem.o > + > vpd-sysfs-y := vpd.o vpd_decode.o > obj-$(CONFIG_GOOGLE_VPD) += vpd-sysfs.o > diff --git a/drivers/firmware/google/cbmem.c b/drivers/firmware/google/cbmem.c > new file mode 100644 > index 000000000000..9646a8047742 > --- /dev/null > +++ b/drivers/firmware/google/cbmem.c > @@ -0,0 +1,232 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * cbmem.c > + * > + * Driver for exporting cbmem entries in sysfs. > + * > + * Copyright 2022 Google LLC > + */ > + > +#include <linux/ctype.h> > +#include <linux/device.h> > +#include <linux/init.h> > +#include <linux/io.h> > +#include <linux/kernel.h> > +#include <linux/kobject.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/slab.h> > +#include <linux/sysfs.h> > + > +#include "coreboot_table.h" > + > +#define LB_TAG_CBMEM_ENTRY 0x31 > + > +static struct kobject *coreboot_kobj; > + > +struct cbmem_entry; > +struct cbmem_entry_attr { > + struct kobj_attribute kobj_attr; > + struct cbmem_entry *entry; > +}; > + > +struct cbmem_entry { > + char *kobj_name; > + struct kobject *kobj; > + struct coreboot_device *dev; > + struct bin_attribute mem_file; > + char *mem_file_buf; > + struct cbmem_entry_attr address_file; > + struct cbmem_entry_attr size_file; > + struct cbmem_entry_attr id_file; > +}; > + > +static struct cbmem_entry_attr *to_cbmem_entry_attr(struct kobj_attribute *a) > +{ > + return container_of(a, struct cbmem_entry_attr, kobj_attr); > +} > + > +static ssize_t cbmem_entry_mem_read(struct file *filp, struct kobject *kobp, > + struct bin_attribute *bin_attr, char *buf, > + loff_t pos, size_t count) > +{ > + struct cbmem_entry *entry = bin_attr->private; > + > + return memory_read_from_buffer(buf, count, &pos, entry->mem_file_buf, > + bin_attr->size); > +} > + > +static ssize_t cbmem_entry_mem_write(struct file *filp, struct kobject *kobp, > + struct bin_attribute *bin_attr, char *buf, > + loff_t pos, size_t count) > +{ > + struct cbmem_entry *entry = bin_attr->private; > + > + if (pos < 0 || pos >= bin_attr->size) > + return -EINVAL; > + if (count > bin_attr->size - pos) > + count = bin_attr->size - pos; > + > + memcpy(entry->mem_file_buf + pos, buf, count); > + return count; > +} > + > +static ssize_t cbmem_entry_address_show(struct kobject *kobj, > + struct kobj_attribute *a, char *buf) > +{ > + struct cbmem_entry_attr *entry_attr = to_cbmem_entry_attr(a); > + > + return sysfs_emit(buf, "0x%llx\n", > + entry_attr->entry->dev->cbmem_entry.address); > +} > + > +static ssize_t cbmem_entry_size_show(struct kobject *kobj, > + struct kobj_attribute *a, char *buf) > +{ > + struct cbmem_entry_attr *entry_attr = to_cbmem_entry_attr(a); > + > + return sysfs_emit(buf, "0x%x\n", > + entry_attr->entry->dev->cbmem_entry.entry_size); > +} > + > +static ssize_t cbmem_entry_id_show(struct kobject *kobj, > + struct kobj_attribute *a, char *buf) > +{ > + struct cbmem_entry_attr *entry_attr = to_cbmem_entry_attr(a); > + > + return sysfs_emit(buf, "0x%x\n", > + entry_attr->entry->dev->cbmem_entry.id); > +} > + > +static int cbmem_entry_setup(struct cbmem_entry *entry) > +{ > + int ret; > + > + entry->mem_file_buf = > + devm_memremap(&entry->dev->dev, entry->dev->cbmem_entry.address, > + entry->dev->cbmem_entry.entry_size, MEMREMAP_WB); > + if (!entry->mem_file_buf) > + return -ENOMEM; > + > + entry->kobj_name = devm_kasprintf(&entry->dev->dev, GFP_KERNEL, > + "cbmem-%08x", > + entry->dev->cbmem_entry.id); > + if (!entry->kobj_name) > + return -ENOMEM; > + > + entry->kobj = kobject_create_and_add(entry->kobj_name, coreboot_kobj); > + if (!entry->kobj) > + return -ENOMEM; > + > + sysfs_bin_attr_init(&entry->mem_file); > + entry->mem_file.attr.name = "mem"; > + entry->mem_file.attr.mode = 0664; > + entry->mem_file.size = entry->dev->cbmem_entry.entry_size; > + entry->mem_file.read = cbmem_entry_mem_read; > + entry->mem_file.write = cbmem_entry_mem_write; > + entry->mem_file.private = entry; > + ret = sysfs_create_bin_file(entry->kobj, &entry->mem_file); > + if (ret) > + goto free_kobj; > + > + sysfs_attr_init(&entry->address_file.kobj_attr.attr); > + entry->address_file.kobj_attr.attr.name = "address"; > + entry->address_file.kobj_attr.attr.mode = 0444; > + entry->address_file.kobj_attr.show = cbmem_entry_address_show; > + entry->address_file.entry = entry; > + ret = sysfs_create_file(entry->kobj, > + &entry->address_file.kobj_attr.attr); > + if (ret) > + goto free_mem_file; > + > + sysfs_attr_init(&entry->size_file.kobj_attr.attr); > + entry->size_file.kobj_attr.attr.name = "size"; > + entry->size_file.kobj_attr.attr.mode = 0444; > + entry->size_file.kobj_attr.show = cbmem_entry_size_show; > + entry->size_file.entry = entry; > + ret = sysfs_create_file(entry->kobj, &entry->size_file.kobj_attr.attr); > + if (ret) > + goto free_address_file; > + > + sysfs_attr_init(&entry->id_file.kobj_attr.attr); > + entry->id_file.kobj_attr.attr.name = "id"; > + entry->id_file.kobj_attr.attr.mode = 0444; > + entry->id_file.kobj_attr.show = cbmem_entry_id_show; > + entry->id_file.entry = entry; > + ret = sysfs_create_file(entry->kobj, &entry->id_file.kobj_attr.attr); > + if (ret) > + goto free_size_file; > + > + return 0; > + > +free_size_file: > + sysfs_remove_file(entry->kobj, &entry->size_file.kobj_attr.attr); > +free_address_file: > + sysfs_remove_file(entry->kobj, &entry->address_file.kobj_attr.attr); > +free_mem_file: > + sysfs_remove_bin_file(entry->kobj, &entry->mem_file); > +free_kobj: > + kobject_put(entry->kobj); > + return ret; > +} > + > +static int cbmem_entry_probe(struct coreboot_device *dev) > +{ > + struct cbmem_entry *entry; > + > + entry = devm_kzalloc(&dev->dev, sizeof(*entry), GFP_KERNEL); > + if (!entry) > + return -ENOMEM; > + > + dev_set_drvdata(&dev->dev, entry); > + entry->dev = dev; > + return cbmem_entry_setup(entry); > +} > + > +static void cbmem_entry_remove(struct coreboot_device *dev) > +{ > + struct cbmem_entry *entry = dev_get_drvdata(&dev->dev); > + > + sysfs_remove_bin_file(entry->kobj, &entry->mem_file); > + sysfs_remove_file(entry->kobj, &entry->address_file.kobj_attr.attr); > + sysfs_remove_file(entry->kobj, &entry->size_file.kobj_attr.attr); > + sysfs_remove_file(entry->kobj, &entry->id_file.kobj_attr.attr); > + kobject_put(entry->kobj); > +} > + > +static struct coreboot_driver cbmem_entry_driver = { > + .probe = cbmem_entry_probe, > + .remove = cbmem_entry_remove, > + .drv = { > + .name = "cbmem", > + }, > + .tag = LB_TAG_CBMEM_ENTRY, > +}; > + > +static int __init cbmem_init(void) > +{ > + int ret; > + > + coreboot_kobj = kobject_create_and_add("coreboot", firmware_kobj); > + if (!coreboot_kobj) > + return -ENOMEM; > + > + ret = coreboot_driver_register(&cbmem_entry_driver); > + if (ret) { > + kobject_put(coreboot_kobj); > + return ret; > + } > + > + return 0; > +} > +module_init(cbmem_init); > + > +static void __exit cbmem_exit(void) > +{ > + kobject_put(coreboot_kobj); > + coreboot_driver_unregister(&cbmem_entry_driver); > +} > +module_exit(cbmem_exit); > + > +MODULE_AUTHOR("Jack Rosenthal <jrosenth@chromium.org>"); > +MODULE_LICENSE("GPL"); > diff --git a/drivers/firmware/google/coreboot_table.h b/drivers/firmware/google/coreboot_table.h > index beb778674acd..6c03a8852d1b 100644 > --- a/drivers/firmware/google/coreboot_table.h > +++ b/drivers/firmware/google/coreboot_table.h > @@ -39,6 +39,16 @@ struct lb_cbmem_ref { > u64 cbmem_addr; > }; > > +/* Corresponds to LB_TAG_CBMEM_ENTRY. */ > +struct lb_cbmem_entry { > + u32 tag; > + u32 size; > + > + u64 address; > + u32 entry_size; > + u32 id; > +}; > + > /* Describes framebuffer setup by coreboot */ > struct lb_framebuffer { > u32 tag; > @@ -65,6 +75,7 @@ struct coreboot_device { > union { > struct coreboot_table_entry entry; > struct lb_cbmem_ref cbmem_ref; > + struct lb_cbmem_entry cbmem_entry; > struct lb_framebuffer framebuffer; > }; > }; > -- > 2.37.1.455.g008518b4e5-goog >
On Tue, Aug 02, 2022 at 07:03:43AM -0700, Jack Rosenthal wrote: > cbmem entries can be read from coreboot table > 0x31 (LB_TAG_CBMEM_ENTRY). This commit exports access to cbmem > entries in sysfs under /sys/firmware/coreboot/cbmem-*. > > Link: https://issuetracker.google.com/239604743 I doubt if the Link tag would be useful for public. [...] > Reported-by: kernel test robot <lkp@intel.com> Suggest to drop the Reported-by tag even if the robot reported some compile errors during the development. Given that the patch isn't a fixup but supporting something new (which isn't "reported by" the robot).
On 2022-08-04 at 08:22 +0000, Tzung-Bi Shih wrote: > On Tue, Aug 02, 2022 at 07:03:43AM -0700, Jack Rosenthal wrote: > > Link: https://issuetracker.google.com/239604743 > > I doubt if the Link tag would be useful for public. Thanks, made the bug public and kept the link. > > Reported-by: kernel test robot <lkp@intel.com> > > Suggest to drop the Reported-by tag even if the robot reported some compile > errors during the development. Given that the patch isn't a fixup but > supporting something new (which isn't "reported by" the robot). Done.
diff --git a/Documentation/ABI/testing/sysfs-firmware-coreboot b/Documentation/ABI/testing/sysfs-firmware-coreboot new file mode 100644 index 000000000000..2401483bb86c --- /dev/null +++ b/Documentation/ABI/testing/sysfs-firmware-coreboot @@ -0,0 +1,17 @@ +What: /sys/firmware/coreboot/ +Date: July 2022 +Contact: Jack Rosenthal <jrosenth@chromium.org> +Description: + Coreboot-based BIOS firmware provides a variety of information + in CBMEM. Each CBMEM entry can be found via Coreboot tables. + For each CBMEM entry, the following are exposed: + + ======= ======================================================= + address A hexidecimal value of the memory address the data for + the entry begins at. + size The size of the data stored. + id The id corresponding to the entry. A list of ids known + to coreboot can be found in the coreboot source tree at + ``src/commonlib/bsd/include/commonlib/bsd/cbmem_id.h`` + mem A file exposing the raw memory for the entry. + ======= ======================================================= diff --git a/drivers/firmware/google/Kconfig b/drivers/firmware/google/Kconfig index 983e07dc022e..bf8316d1cb31 100644 --- a/drivers/firmware/google/Kconfig +++ b/drivers/firmware/google/Kconfig @@ -19,6 +19,14 @@ config GOOGLE_SMI driver provides an interface for reading and writing NVRAM variables. +config GOOGLE_CBMEM + tristate "CBMEM entries in sysfs" + depends on GOOGLE_COREBOOT_TABLE + help + This option enables the kernel to search for Coreboot CBMEM + entries, and expose the memory for each entry in sysfs under + /sys/firmware/coreboot. + config GOOGLE_COREBOOT_TABLE tristate "Coreboot Table Access" depends on HAS_IOMEM && (ACPI || OF) diff --git a/drivers/firmware/google/Makefile b/drivers/firmware/google/Makefile index d17caded5d88..8151e323cc43 100644 --- a/drivers/firmware/google/Makefile +++ b/drivers/firmware/google/Makefile @@ -7,5 +7,8 @@ obj-$(CONFIG_GOOGLE_MEMCONSOLE) += memconsole.o obj-$(CONFIG_GOOGLE_MEMCONSOLE_COREBOOT) += memconsole-coreboot.o obj-$(CONFIG_GOOGLE_MEMCONSOLE_X86_LEGACY) += memconsole-x86-legacy.o +# Must come after coreboot_table.o, as this driver depends on that bus type. +obj-$(CONFIG_GOOGLE_CBMEM) += cbmem.o + vpd-sysfs-y := vpd.o vpd_decode.o obj-$(CONFIG_GOOGLE_VPD) += vpd-sysfs.o diff --git a/drivers/firmware/google/cbmem.c b/drivers/firmware/google/cbmem.c new file mode 100644 index 000000000000..9646a8047742 --- /dev/null +++ b/drivers/firmware/google/cbmem.c @@ -0,0 +1,232 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * cbmem.c + * + * Driver for exporting cbmem entries in sysfs. + * + * Copyright 2022 Google LLC + */ + +#include <linux/ctype.h> +#include <linux/device.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kobject.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/sysfs.h> + +#include "coreboot_table.h" + +#define LB_TAG_CBMEM_ENTRY 0x31 + +static struct kobject *coreboot_kobj; + +struct cbmem_entry; +struct cbmem_entry_attr { + struct kobj_attribute kobj_attr; + struct cbmem_entry *entry; +}; + +struct cbmem_entry { + char *kobj_name; + struct kobject *kobj; + struct coreboot_device *dev; + struct bin_attribute mem_file; + char *mem_file_buf; + struct cbmem_entry_attr address_file; + struct cbmem_entry_attr size_file; + struct cbmem_entry_attr id_file; +}; + +static struct cbmem_entry_attr *to_cbmem_entry_attr(struct kobj_attribute *a) +{ + return container_of(a, struct cbmem_entry_attr, kobj_attr); +} + +static ssize_t cbmem_entry_mem_read(struct file *filp, struct kobject *kobp, + struct bin_attribute *bin_attr, char *buf, + loff_t pos, size_t count) +{ + struct cbmem_entry *entry = bin_attr->private; + + return memory_read_from_buffer(buf, count, &pos, entry->mem_file_buf, + bin_attr->size); +} + +static ssize_t cbmem_entry_mem_write(struct file *filp, struct kobject *kobp, + struct bin_attribute *bin_attr, char *buf, + loff_t pos, size_t count) +{ + struct cbmem_entry *entry = bin_attr->private; + + if (pos < 0 || pos >= bin_attr->size) + return -EINVAL; + if (count > bin_attr->size - pos) + count = bin_attr->size - pos; + + memcpy(entry->mem_file_buf + pos, buf, count); + return count; +} + +static ssize_t cbmem_entry_address_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct cbmem_entry_attr *entry_attr = to_cbmem_entry_attr(a); + + return sysfs_emit(buf, "0x%llx\n", + entry_attr->entry->dev->cbmem_entry.address); +} + +static ssize_t cbmem_entry_size_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct cbmem_entry_attr *entry_attr = to_cbmem_entry_attr(a); + + return sysfs_emit(buf, "0x%x\n", + entry_attr->entry->dev->cbmem_entry.entry_size); +} + +static ssize_t cbmem_entry_id_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct cbmem_entry_attr *entry_attr = to_cbmem_entry_attr(a); + + return sysfs_emit(buf, "0x%x\n", + entry_attr->entry->dev->cbmem_entry.id); +} + +static int cbmem_entry_setup(struct cbmem_entry *entry) +{ + int ret; + + entry->mem_file_buf = + devm_memremap(&entry->dev->dev, entry->dev->cbmem_entry.address, + entry->dev->cbmem_entry.entry_size, MEMREMAP_WB); + if (!entry->mem_file_buf) + return -ENOMEM; + + entry->kobj_name = devm_kasprintf(&entry->dev->dev, GFP_KERNEL, + "cbmem-%08x", + entry->dev->cbmem_entry.id); + if (!entry->kobj_name) + return -ENOMEM; + + entry->kobj = kobject_create_and_add(entry->kobj_name, coreboot_kobj); + if (!entry->kobj) + return -ENOMEM; + + sysfs_bin_attr_init(&entry->mem_file); + entry->mem_file.attr.name = "mem"; + entry->mem_file.attr.mode = 0664; + entry->mem_file.size = entry->dev->cbmem_entry.entry_size; + entry->mem_file.read = cbmem_entry_mem_read; + entry->mem_file.write = cbmem_entry_mem_write; + entry->mem_file.private = entry; + ret = sysfs_create_bin_file(entry->kobj, &entry->mem_file); + if (ret) + goto free_kobj; + + sysfs_attr_init(&entry->address_file.kobj_attr.attr); + entry->address_file.kobj_attr.attr.name = "address"; + entry->address_file.kobj_attr.attr.mode = 0444; + entry->address_file.kobj_attr.show = cbmem_entry_address_show; + entry->address_file.entry = entry; + ret = sysfs_create_file(entry->kobj, + &entry->address_file.kobj_attr.attr); + if (ret) + goto free_mem_file; + + sysfs_attr_init(&entry->size_file.kobj_attr.attr); + entry->size_file.kobj_attr.attr.name = "size"; + entry->size_file.kobj_attr.attr.mode = 0444; + entry->size_file.kobj_attr.show = cbmem_entry_size_show; + entry->size_file.entry = entry; + ret = sysfs_create_file(entry->kobj, &entry->size_file.kobj_attr.attr); + if (ret) + goto free_address_file; + + sysfs_attr_init(&entry->id_file.kobj_attr.attr); + entry->id_file.kobj_attr.attr.name = "id"; + entry->id_file.kobj_attr.attr.mode = 0444; + entry->id_file.kobj_attr.show = cbmem_entry_id_show; + entry->id_file.entry = entry; + ret = sysfs_create_file(entry->kobj, &entry->id_file.kobj_attr.attr); + if (ret) + goto free_size_file; + + return 0; + +free_size_file: + sysfs_remove_file(entry->kobj, &entry->size_file.kobj_attr.attr); +free_address_file: + sysfs_remove_file(entry->kobj, &entry->address_file.kobj_attr.attr); +free_mem_file: + sysfs_remove_bin_file(entry->kobj, &entry->mem_file); +free_kobj: + kobject_put(entry->kobj); + return ret; +} + +static int cbmem_entry_probe(struct coreboot_device *dev) +{ + struct cbmem_entry *entry; + + entry = devm_kzalloc(&dev->dev, sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + dev_set_drvdata(&dev->dev, entry); + entry->dev = dev; + return cbmem_entry_setup(entry); +} + +static void cbmem_entry_remove(struct coreboot_device *dev) +{ + struct cbmem_entry *entry = dev_get_drvdata(&dev->dev); + + sysfs_remove_bin_file(entry->kobj, &entry->mem_file); + sysfs_remove_file(entry->kobj, &entry->address_file.kobj_attr.attr); + sysfs_remove_file(entry->kobj, &entry->size_file.kobj_attr.attr); + sysfs_remove_file(entry->kobj, &entry->id_file.kobj_attr.attr); + kobject_put(entry->kobj); +} + +static struct coreboot_driver cbmem_entry_driver = { + .probe = cbmem_entry_probe, + .remove = cbmem_entry_remove, + .drv = { + .name = "cbmem", + }, + .tag = LB_TAG_CBMEM_ENTRY, +}; + +static int __init cbmem_init(void) +{ + int ret; + + coreboot_kobj = kobject_create_and_add("coreboot", firmware_kobj); + if (!coreboot_kobj) + return -ENOMEM; + + ret = coreboot_driver_register(&cbmem_entry_driver); + if (ret) { + kobject_put(coreboot_kobj); + return ret; + } + + return 0; +} +module_init(cbmem_init); + +static void __exit cbmem_exit(void) +{ + kobject_put(coreboot_kobj); + coreboot_driver_unregister(&cbmem_entry_driver); +} +module_exit(cbmem_exit); + +MODULE_AUTHOR("Jack Rosenthal <jrosenth@chromium.org>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/firmware/google/coreboot_table.h b/drivers/firmware/google/coreboot_table.h index beb778674acd..6c03a8852d1b 100644 --- a/drivers/firmware/google/coreboot_table.h +++ b/drivers/firmware/google/coreboot_table.h @@ -39,6 +39,16 @@ struct lb_cbmem_ref { u64 cbmem_addr; }; +/* Corresponds to LB_TAG_CBMEM_ENTRY. */ +struct lb_cbmem_entry { + u32 tag; + u32 size; + + u64 address; + u32 entry_size; + u32 id; +}; + /* Describes framebuffer setup by coreboot */ struct lb_framebuffer { u32 tag; @@ -65,6 +75,7 @@ struct coreboot_device { union { struct coreboot_table_entry entry; struct lb_cbmem_ref cbmem_ref; + struct lb_cbmem_entry cbmem_entry; struct lb_framebuffer framebuffer; }; };