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linux-stable/drivers/firmware/google/framebuffer-coreboot.c

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 287 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license v2 0 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 23 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.115786599@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-29 14:18:01 +00:00
// SPDX-License-Identifier: GPL-2.0-only
firmware: coreboot: Add coreboot framebuffer driver Register a simplefb framebuffer when the coreboot table contains a framebuffer entry. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-25 01:41:20 +00:00
/*
* framebuffer-coreboot.c
*
* Memory based framebuffer accessed through coreboot table.
*
* Copyright 2012-2013 David Herrmann <dh.herrmann@gmail.com>
* Copyright 2017 Google Inc.
* Copyright 2017 Samuel Holland <samuel@sholland.org>
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_data/simplefb.h>
#include <linux/platform_device.h>
#include "coreboot_table.h"
#define CB_TAG_FRAMEBUFFER 0x12
static const struct simplefb_format formats[] = SIMPLEFB_FORMATS;
static int framebuffer_probe(struct coreboot_device *dev)
{
int i;
u32 length;
struct lb_framebuffer *fb = &dev->framebuffer;
struct platform_device *pdev;
struct resource res;
struct simplefb_platform_data pdata = {
.width = fb->x_resolution,
.height = fb->y_resolution,
.stride = fb->bytes_per_line,
.format = NULL,
};
firmware: coreboot: framebuffer: Avoid invalid zero physical address On ARM64 systems coreboot defers framebuffer allocation to its payload, to be done by a libpayload function call. In this case, coreboot tables still include a framebuffer entry with display format details, but the physical address field is set to zero (as in [1], for example). Unfortunately, this field is not automatically updated when the framebuffer is initialized through libpayload, citing that doing so would invalidate checksums over the entire coreboot table [2]. This can be observed on ARM64 Chromebooks with stock firmware. On a Google Kevin (RK3399), trying to use coreboot framebuffer driver as built-in to the kernel results in a benign error. But on Google Hana (MT8173) and Google Cozmo (MT8183) it causes a hang. When the framebuffer physical address field in the coreboot table is zero, we have no idea where coreboot initialized a framebuffer, or even if it did. Instead of trying to set up a framebuffer located at zero, return ENODEV to indicate that there isn't one. [1] https://review.coreboot.org/c/coreboot/+/17109 [2] https://review.coreboot.org/c/coreboot/+/8797 Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com> Reviewed-by: Julius Werner <jwerner@chromium.org> Link: https://lore.kernel.org/r/20231108182625.46563-1-alpernebiyasak@gmail.com Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
2023-11-08 18:25:13 +00:00
if (!fb->physical_address)
return -ENODEV;
firmware: coreboot: Add coreboot framebuffer driver Register a simplefb framebuffer when the coreboot table contains a framebuffer entry. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-25 01:41:20 +00:00
for (i = 0; i < ARRAY_SIZE(formats); ++i) {
if (fb->bits_per_pixel == formats[i].bits_per_pixel &&
fb->red_mask_pos == formats[i].red.offset &&
fb->red_mask_size == formats[i].red.length &&
fb->green_mask_pos == formats[i].green.offset &&
fb->green_mask_size == formats[i].green.length &&
fb->blue_mask_pos == formats[i].blue.offset &&
firmware: coreboot: framebuffer: Ignore reserved pixel color bits The coreboot framebuffer doesn't support transparency, its 'reserved' bit field is merely padding for byte/word alignment of pixel colors [1]. When trying to match the framebuffer to a simplefb format, the kernel driver unnecessarily requires the format's transparency bit field to exactly match this padding, even if the former is zero-width. Due to a coreboot bug [2] (fixed upstream), some boards misreport the reserved field's size as equal to its position (0x18 for both on a 'Lick' Chromebook), and the driver fails to probe where it would have otherwise worked fine with e.g. the a8r8g8b8 or x8r8g8b8 formats. Remove the transparency comparison with reserved bits. When the bits-per-pixel and other color components match, transparency will already be in a subset of the reserved field. Not forcing it to match reserved bits allows the driver to work on the boards which misreport the reserved field. It also enables using simplefb formats that don't have transparency bits, although this doesn't currently happen due to format support and ordering in linux/platform_data/simplefb.h. [1] https://review.coreboot.org/plugins/gitiles/coreboot/+/4.19/src/commonlib/include/commonlib/coreboot_tables.h#255 [2] https://review.coreboot.org/plugins/gitiles/coreboot/+/4.13/src/drivers/intel/fsp2_0/graphics.c#82 Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com> Link: https://lore.kernel.org/r/20230122190433.195941-1-alpernebiyasak@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-22 19:04:31 +00:00
fb->blue_mask_size == formats[i].blue.length)
firmware: coreboot: Add coreboot framebuffer driver Register a simplefb framebuffer when the coreboot table contains a framebuffer entry. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-25 01:41:20 +00:00
pdata.format = formats[i].name;
}
if (!pdata.format)
return -ENODEV;
memset(&res, 0, sizeof(res));
res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
res.name = "Coreboot Framebuffer";
res.start = fb->physical_address;
length = PAGE_ALIGN(fb->y_resolution * fb->bytes_per_line);
res.end = res.start + length - 1;
if (res.end <= res.start)
return -EINVAL;
pdev = platform_device_register_resndata(&dev->dev,
"simple-framebuffer", 0,
&res, 1, &pdata,
sizeof(pdata));
if (IS_ERR(pdev))
pr_warn("coreboot: could not register framebuffer\n");
else
dev_set_drvdata(&dev->dev, pdev);
return PTR_ERR_OR_ZERO(pdev);
}
firmware: google: make coreboot driver's remove callback return void All coreboot drivers return 0 unconditionally in their remove callback. Also the device core ignores the return value of the struct bus_type::remove(), so make the coreboot remove callback return void instead of giving driver authors the illusion they could return an error code here. All drivers are adapted accordingly. Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> Link: https://lore.kernel.org/r/20210126215339.706021-1-uwe@kleine-koenig.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-26 21:53:39 +00:00
static void framebuffer_remove(struct coreboot_device *dev)
firmware: coreboot: Add coreboot framebuffer driver Register a simplefb framebuffer when the coreboot table contains a framebuffer entry. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-25 01:41:20 +00:00
{
struct platform_device *pdev = dev_get_drvdata(&dev->dev);
platform_device_unregister(pdev);
}
firmware: coreboot: Replace tag with id table in driver struct Switch the plain 'tag' field in struct coreboot_driver for the newly created coreboot_device_id struct, which also contains a tag field and has the benefit of allowing modalias generation, and update all coreboot drivers accordingly. While at it, also add the id table for each driver to the module device table to allow automatically loading the module. Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Link: https://lore.kernel.org/r/20240212-coreboot-mod-defconfig-v4-3-d14172676f6d@collabora.com Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
2024-02-12 14:50:07 +00:00
static const struct coreboot_device_id framebuffer_ids[] = {
{ .tag = CB_TAG_FRAMEBUFFER },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(coreboot, framebuffer_ids);
firmware: coreboot: Add coreboot framebuffer driver Register a simplefb framebuffer when the coreboot table contains a framebuffer entry. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-25 01:41:20 +00:00
static struct coreboot_driver framebuffer_driver = {
.probe = framebuffer_probe,
.remove = framebuffer_remove,
.drv = {
.name = "framebuffer",
},
firmware: coreboot: Replace tag with id table in driver struct Switch the plain 'tag' field in struct coreboot_driver for the newly created coreboot_device_id struct, which also contains a tag field and has the benefit of allowing modalias generation, and update all coreboot drivers accordingly. While at it, also add the id table for each driver to the module device table to allow automatically loading the module. Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Link: https://lore.kernel.org/r/20240212-coreboot-mod-defconfig-v4-3-d14172676f6d@collabora.com Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
2024-02-12 14:50:07 +00:00
.id_table = framebuffer_ids,
firmware: coreboot: Add coreboot framebuffer driver Register a simplefb framebuffer when the coreboot table contains a framebuffer entry. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-25 01:41:20 +00:00
};
firmware: google: Add a module_coreboot_driver() macro and use it Remove some boiler plate code we have in three drivers with a single line each time. This also gets us a free assignment of the driver .owner field, making these drivers work better as modules. Cc: Wei-Ning Huang <wnhuang@chromium.org> Cc: Julius Werner <jwerner@chromium.org> Cc: Brian Norris <briannorris@chromium.org> Cc: Samuel Holland <samuel@sholland.org> Cc: Guenter Roeck <groeck@chromium.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-10 18:01:47 +00:00
module_coreboot_driver(framebuffer_driver);
firmware: coreboot: Add coreboot framebuffer driver Register a simplefb framebuffer when the coreboot table contains a framebuffer entry. Signed-off-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-25 01:41:20 +00:00
MODULE_AUTHOR("Samuel Holland <samuel@sholland.org>");
MODULE_LICENSE("GPL");