Quoting [email protected] (2020-04-07 01:29:07) > From: Patrick Rudolph <[email protected]> > > Make all coreboot table entries available to userland. This is useful for > tools that are currently using /dev/mem. > > Besides the tag and size also expose the raw table data itself. > > Update the ABI documentation to explain the new sysfs interface. > > Tools can easily scan for the right coreboot table by reading > /sys/bus/coreboot/devices/coreboot*/attributes/id > The binary table data can then be read from > /sys/bus/coreboot/devices/coreboot*/attributes/data > > Signed-off-by: Patrick Rudolph <[email protected]> > ---
Reviewed-by: Stephen Boyd <[email protected]> Minor nits below: > -v2: > - Add ABI documentation > - Add 0x prefix on hex values > - Remove wrong ioremap hint as found by CI > -v3: > - Use BIN_ATTR_RO > -v4: > - Updated ABI documentation > --- > Documentation/ABI/stable/sysfs-bus-coreboot | 30 +++++++++++ > drivers/firmware/google/coreboot_table.c | 58 +++++++++++++++++++++ > 2 files changed, 88 insertions(+) > > diff --git a/Documentation/ABI/stable/sysfs-bus-coreboot > b/Documentation/ABI/stable/sysfs-bus-coreboot > index 6055906f41f2..328153a1b3f4 100644 > --- a/Documentation/ABI/stable/sysfs-bus-coreboot > +++ b/Documentation/ABI/stable/sysfs-bus-coreboot > diff --git a/drivers/firmware/google/coreboot_table.c > b/drivers/firmware/google/coreboot_table.c > index 0205987a4fd4..d0fc3eb93f4f 100644 > --- a/drivers/firmware/google/coreboot_table.c > +++ b/drivers/firmware/google/coreboot_table.c > @@ -3,9 +3,11 @@ > * coreboot_table.c > * > * Module providing coreboot table access. > + * Exports coreboot tables as attributes in sysfs. > * > * Copyright 2017 Google Inc. > * Copyright 2017 Samuel Holland <[email protected]> > + * Copyright 2019 9elements Agency GmbH > */ > > #include <linux/acpi.h> > @@ -84,6 +86,60 @@ void coreboot_driver_unregister(struct coreboot_driver > *driver) > } > EXPORT_SYMBOL(coreboot_driver_unregister); > > +static ssize_t id_show(struct device *dev, > + struct device_attribute *attr, char *buffer) > +{ > + struct coreboot_device *device = CB_DEV(dev); Wouldn't hurt to throw const in front of these. > + > + return sprintf(buffer, "0x%08x\n", device->entry.tag); > +} > + > +static ssize_t size_show(struct device *dev, > + struct device_attribute *attr, char *buffer) > +{ > + struct coreboot_device *device = CB_DEV(dev); And these. But the function is so short probably doesn't really matter. > + > + return sprintf(buffer, "%u\n", device->entry.size); > +} > + > +static DEVICE_ATTR_RO(id); > +static DEVICE_ATTR_RO(size); > + > +static struct attribute *cb_dev_attrs[] = { > + &dev_attr_id.attr, > + &dev_attr_size.attr, > + NULL > +}; > + > +static ssize_t data_read(struct file *filp, struct kobject *kobj, > + struct bin_attribute *bin_attr, > + char *buffer, loff_t offset, size_t count) > +{ > + struct device *dev = kobj_to_dev(kobj); > + struct coreboot_device *device = CB_DEV(dev); > + > + return memory_read_from_buffer(buffer, count, &offset, > + &device->entry, device->entry.size); > +} > + > +static BIN_ATTR_RO(data, 0); Still no way to figure out the actual size? Can we add the bin_attribute at runtime? > + > +static struct bin_attribute *cb_dev_bin_attrs[] = { > + &bin_attr_data, > + NULL > +}; > +
