2022-08-06 16:37:42

by Markuss Broks

[permalink] [raw]
Subject: [PATCH v2 0/3] Add generic framebuffer support to EFI earlycon driver

Make the EFI earlycon driver be suitable for any linear framebuffers.
This should be helpful for early porting of boards with no other means of
output, like smartphones/tablets. There seems to be an issue with early_ioremap
function on ARM32, but I am unable to find the exact cause. It appears the mappings
returned by it are somehow incorrect, thus the driver is disabled on ARM. EFI early
console was disabled on IA64 previously because of missing early_memremap_prot,
and this is inherited to this driver.

This patch also changes behavior on EFI systems, by selecting the mapping type
based on if the framebuffer region intersects with system RAM. If it does, it's
common sense that it should be in RAM as a whole, and so the system RAM mapping is
used. It was tested to be working on my PC (Intel Z490 platform), as well as several
ARM64 boards (Samsung Galaxy S9 (Exynos), iPad Air 2, Xiaomi Mi Pad 4, ...).

Markuss Broks (2):
drivers: serial: earlycon: Pass device-tree node
efi: earlycon: Add support for generic framebuffers and move to fbdev
subsystem


v1 -> v2:

- a new patch correcting serial/earlycon.c argument name to "offset" instead
of "node"
- move IA64 exclusion from EFI earlycon Kconfig to earlycon driver Kconfig
(IA64 has no early_memremap_prot)
- move driver from fbdev to console subsystem
- select EFI earlycon by default
- fetch stride manually from device-tree, as on some devices it seems stride
doesn't match the horizontal resolution * bpp.
- use saner format (e.g. 1920x1080x32 instead of 1920,1080,32).

.../admin-guide/kernel-parameters.txt | 12 +-
MAINTAINERS | 5 +
drivers/firmware/efi/Kconfig | 6 +-
drivers/firmware/efi/Makefile | 1 -
drivers/firmware/efi/earlycon.c | 246 --------------
drivers/tty/serial/earlycon.c | 3 +
drivers/video/fbdev/Kconfig | 11 +
drivers/video/fbdev/Makefile | 1 +
drivers/video/fbdev/earlycon.c | 301 ++++++++++++++++++
include/linux/serial_core.h | 1 +
10 files changed, 331 insertions(+), 256 deletions(-)
delete mode 100644 drivers/firmware/efi/earlycon.c
create mode 100644 drivers/video/fbdev/earlycon.c

--
2.37.0


2022-08-06 16:38:11

by Markuss Broks

[permalink] [raw]
Subject: [PATCH v2 1/3] drivers: serial: earlycon: Correct argument name

The "node" argument is actually an offset, and it's also
an "int", and not "unsigned long". Correct the of_setup_earlycon
function.

Signed-off-by: Markuss Broks <[email protected]>
---
drivers/tty/serial/earlycon.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 57c70851f22a0e78805f34d1a7700708104b6f6a..bc210ae8173d97d5ef422468acf2755a853cb943 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -244,7 +244,7 @@ early_param("earlycon", param_setup_earlycon);
#ifdef CONFIG_OF_EARLY_FLATTREE

int __init of_setup_earlycon(const struct earlycon_id *match,
- unsigned long node,
+ int offset,
const char *options)
{
int err;
@@ -255,25 +255,25 @@ int __init of_setup_earlycon(const struct earlycon_id *match,

spin_lock_init(&port->lock);
port->iotype = UPIO_MEM;
- addr = of_flat_dt_translate_address(node);
+ addr = of_flat_dt_translate_address(offset);
if (addr == OF_BAD_ADDR) {
pr_warn("[%s] bad address\n", match->name);
return -ENXIO;
}
port->mapbase = addr;

- val = of_get_flat_dt_prop(node, "reg-offset", NULL);
+ val = of_get_flat_dt_prop(offset, "reg-offset", NULL);
if (val)
port->mapbase += be32_to_cpu(*val);
port->membase = earlycon_map(port->mapbase, SZ_4K);

- val = of_get_flat_dt_prop(node, "reg-shift", NULL);
+ val = of_get_flat_dt_prop(offset, "reg-shift", NULL);
if (val)
port->regshift = be32_to_cpu(*val);
- big_endian = of_get_flat_dt_prop(node, "big-endian", NULL) != NULL ||
+ big_endian = of_get_flat_dt_prop(offset, "big-endian", NULL) != NULL ||
(IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
- of_get_flat_dt_prop(node, "native-endian", NULL) != NULL);
- val = of_get_flat_dt_prop(node, "reg-io-width", NULL);
+ of_get_flat_dt_prop(offset, "native-endian", NULL) != NULL);
+ val = of_get_flat_dt_prop(offset, "reg-io-width", NULL);
if (val) {
switch (be32_to_cpu(*val)) {
case 1:
@@ -291,11 +291,11 @@ int __init of_setup_earlycon(const struct earlycon_id *match,
}
}

- val = of_get_flat_dt_prop(node, "current-speed", NULL);
+ val = of_get_flat_dt_prop(offset, "current-speed", NULL);
if (val)
early_console_dev.baud = be32_to_cpu(*val);

- val = of_get_flat_dt_prop(node, "clock-frequency", NULL);
+ val = of_get_flat_dt_prop(offset, "clock-frequency", NULL);
if (val)
port->uartclk = be32_to_cpu(*val);

--
2.37.0

2022-08-06 16:40:45

by Markuss Broks

[permalink] [raw]
Subject: [PATCH v2 2/3] drivers: serial: earlycon: Pass device-tree node

Pass a pointer to device-tree node in case the driver probed from
OF. This makes early console drivers able to fetch options from
device-tree node properties.

Signed-off-by: Markuss Broks <[email protected]>
---
drivers/tty/serial/earlycon.c | 3 +++
include/linux/serial_core.h | 1 +
2 files changed, 4 insertions(+)

diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index bc210ae8173d97d5ef422468acf2755a853cb943..be2f01520f6608f6ece725dd83d2526e30477b47 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -304,6 +304,9 @@ int __init of_setup_earlycon(const struct earlycon_id *match,
strlcpy(early_console_dev.options, options,
sizeof(early_console_dev.options));
}
+
+ early_console_dev.offset = offset;
+
earlycon_init(&early_console_dev, match->name);
err = match->setup(&early_console_dev, options);
earlycon_print_info(&early_console_dev);
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index cbd5070bc87f42aa450c4ca7af8a9b59fbe88574..e65b9aba4e5fdaedb560d2cbbf326a11cfecbcac 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -349,6 +349,7 @@ struct earlycon_device {
struct uart_port port;
char options[16]; /* e.g., 115200n8 */
unsigned int baud;
+ int offset;
};

struct earlycon_id {
--
2.37.0

2022-08-06 16:52:40

by Markuss Broks

[permalink] [raw]
Subject: [PATCH v2 3/3] efi: earlycon: Add support for generic framebuffers and move to console subsystem

Add early console support for generic linear framebuffer devices.
This driver supports probing from cmdline early parameters
or from the device-tree using information in simple-framebuffer node.
The EFI functionality should be retained in whole.
The driver was disabled on ARM because of a bug in early_ioremap
implementation on ARM and on IA64 because of lack of early_memremap_prot.

Signed-off-by: Markuss Broks <[email protected]>
---
.../admin-guide/kernel-parameters.txt | 12 +-
MAINTAINERS | 5 +
drivers/firmware/efi/Kconfig | 7 +-
drivers/firmware/efi/Makefile | 1 -
drivers/firmware/efi/earlycon.c | 246 --------------
drivers/video/console/Kconfig | 11 +
drivers/video/console/Makefile | 1 +
drivers/video/console/earlycon.c | 305 ++++++++++++++++++
8 files changed, 332 insertions(+), 256 deletions(-)
delete mode 100644 drivers/firmware/efi/earlycon.c
create mode 100644 drivers/video/console/earlycon.c

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 8090130b544b0701237a7b657a29c83c000a60f4..bccb1ac8978eb5cf7e2bb20834b1881b27040666 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1281,12 +1281,9 @@
specified address. The serial port must already be
setup and configured. Options are not yet supported.

- efifb,[options]
+ efifb
Start an early, unaccelerated console on the EFI
- memory mapped framebuffer (if available). On cache
- coherent non-x86 systems that use system memory for
- the framebuffer, pass the 'ram' option so that it is
- mapped with the correct attributes.
+ memory mapped framebuffer (if available).

linflex,<addr>
Use early console provided by Freescale LINFlexD UART
@@ -1294,6 +1291,11 @@
address must be provided, and the serial port must
already be setup and configured.

+ simplefb,<addr>,<width>x<height>x<bpp>
+ Use early console with simple framebuffer that is
+ pre-initialized by firmware. A valid base address,
+ width, height and pixel size must be provided.
+
earlyprintk= [X86,SH,ARM,M68k,S390]
earlyprintk=vga
earlyprintk=sclp
diff --git a/MAINTAINERS b/MAINTAINERS
index 1fc9ead83d2aa3e60ccc4cfa8ee16df09ef579bf..af8b8e289483b6a264d477145061bd0e0ba34a25 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7033,6 +7033,11 @@ Q: http://patchwork.linuxtv.org/project/linux-media/list/
T: git git://linuxtv.org/anttip/media_tree.git
F: drivers/media/tuners/e4000*

+EARLY CONSOLE FRAMEBUFFER DRIVER
+M: Markuss Broks <[email protected]>
+S: Maintained
+F: drivers/video/console/earlycon.c
+
EARTH_PT1 MEDIA DRIVER
M: Akihiro Tsukada <[email protected]>
L: [email protected]
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 7aa4717cdcac46f91dd202f868c463388eb02735..ea76ccfb9bcd8ba44ddca06052eaa442ed6c30f7 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -259,10 +259,9 @@ config EFI_DISABLE_PCI_DMA
may be used to override this option.

config EFI_EARLYCON
- def_bool y
- depends on SERIAL_EARLYCON && !ARM && !IA64
- select FONT_SUPPORT
- select ARCH_USE_MEMREMAP_PROT
+ bool "EFI early console support"
+ select FB_EARLYCON
+ default y

config EFI_CUSTOM_SSDT_OVERLAYS
bool "Load custom ACPI SSDT overlay from an EFI variable"
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index c02ff25dd47707090a2ab86ee4f330e467f878f5..64eea61fbb43d76ec2d5416d467dfbb9aa21bda0 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -44,6 +44,5 @@ obj-$(CONFIG_ARM64) += $(arm-obj-y)
riscv-obj-$(CONFIG_EFI) := efi-init.o riscv-runtime.o
obj-$(CONFIG_RISCV) += $(riscv-obj-y)
obj-$(CONFIG_EFI_CAPSULE_LOADER) += capsule-loader.o
-obj-$(CONFIG_EFI_EARLYCON) += earlycon.o
obj-$(CONFIG_UEFI_CPER_ARM) += cper-arm.o
obj-$(CONFIG_UEFI_CPER_X86) += cper-x86.o
diff --git a/drivers/firmware/efi/earlycon.c b/drivers/firmware/efi/earlycon.c
deleted file mode 100644
index a52236e11e5f73ddea5bb1f42ca2ca7c42425dab..0000000000000000000000000000000000000000
--- a/drivers/firmware/efi/earlycon.c
+++ /dev/null
@@ -1,246 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2013 Intel Corporation; author Matt Fleming
- */
-
-#include <linux/console.h>
-#include <linux/efi.h>
-#include <linux/font.h>
-#include <linux/io.h>
-#include <linux/kernel.h>
-#include <linux/serial_core.h>
-#include <linux/screen_info.h>
-
-#include <asm/early_ioremap.h>
-
-static const struct console *earlycon_console __initdata;
-static const struct font_desc *font;
-static u32 efi_x, efi_y;
-static u64 fb_base;
-static bool fb_wb;
-static void *efi_fb;
-
-/*
- * EFI earlycon needs to use early_memremap() to map the framebuffer.
- * But early_memremap() is not usable for 'earlycon=efifb keep_bootcon',
- * memremap() should be used instead. memremap() will be available after
- * paging_init() which is earlier than initcall callbacks. Thus adding this
- * early initcall function early_efi_map_fb() to map the whole EFI framebuffer.
- */
-static int __init efi_earlycon_remap_fb(void)
-{
- /* bail if there is no bootconsole or it has been disabled already */
- if (!earlycon_console || !(earlycon_console->flags & CON_ENABLED))
- return 0;
-
- efi_fb = memremap(fb_base, screen_info.lfb_size,
- fb_wb ? MEMREMAP_WB : MEMREMAP_WC);
-
- return efi_fb ? 0 : -ENOMEM;
-}
-early_initcall(efi_earlycon_remap_fb);
-
-static int __init efi_earlycon_unmap_fb(void)
-{
- /* unmap the bootconsole fb unless keep_bootcon has left it enabled */
- if (efi_fb && !(earlycon_console->flags & CON_ENABLED))
- memunmap(efi_fb);
- return 0;
-}
-late_initcall(efi_earlycon_unmap_fb);
-
-static __ref void *efi_earlycon_map(unsigned long start, unsigned long len)
-{
- pgprot_t fb_prot;
-
- if (efi_fb)
- return efi_fb + start;
-
- fb_prot = fb_wb ? PAGE_KERNEL : pgprot_writecombine(PAGE_KERNEL);
- return early_memremap_prot(fb_base + start, len, pgprot_val(fb_prot));
-}
-
-static __ref void efi_earlycon_unmap(void *addr, unsigned long len)
-{
- if (efi_fb)
- return;
-
- early_memunmap(addr, len);
-}
-
-static void efi_earlycon_clear_scanline(unsigned int y)
-{
- unsigned long *dst;
- u16 len;
-
- len = screen_info.lfb_linelength;
- dst = efi_earlycon_map(y*len, len);
- if (!dst)
- return;
-
- memset(dst, 0, len);
- efi_earlycon_unmap(dst, len);
-}
-
-static void efi_earlycon_scroll_up(void)
-{
- unsigned long *dst, *src;
- u16 len;
- u32 i, height;
-
- len = screen_info.lfb_linelength;
- height = screen_info.lfb_height;
-
- for (i = 0; i < height - font->height; i++) {
- dst = efi_earlycon_map(i*len, len);
- if (!dst)
- return;
-
- src = efi_earlycon_map((i + font->height) * len, len);
- if (!src) {
- efi_earlycon_unmap(dst, len);
- return;
- }
-
- memmove(dst, src, len);
-
- efi_earlycon_unmap(src, len);
- efi_earlycon_unmap(dst, len);
- }
-}
-
-static void efi_earlycon_write_char(u32 *dst, unsigned char c, unsigned int h)
-{
- const u32 color_black = 0x00000000;
- const u32 color_white = 0x00ffffff;
- const u8 *src;
- int m, n, bytes;
- u8 x;
-
- bytes = BITS_TO_BYTES(font->width);
- src = font->data + c * font->height * bytes + h * bytes;
-
- for (m = 0; m < font->width; m++) {
- n = m % 8;
- x = *(src + m / 8);
- if ((x >> (7 - n)) & 1)
- *dst = color_white;
- else
- *dst = color_black;
- dst++;
- }
-}
-
-static void
-efi_earlycon_write(struct console *con, const char *str, unsigned int num)
-{
- struct screen_info *si;
- unsigned int len;
- const char *s;
- void *dst;
-
- si = &screen_info;
- len = si->lfb_linelength;
-
- while (num) {
- unsigned int linemax;
- unsigned int h, count = 0;
-
- for (s = str; *s && *s != '\n'; s++) {
- if (count == num)
- break;
- count++;
- }
-
- linemax = (si->lfb_width - efi_x) / font->width;
- if (count > linemax)
- count = linemax;
-
- for (h = 0; h < font->height; h++) {
- unsigned int n, x;
-
- dst = efi_earlycon_map((efi_y + h) * len, len);
- if (!dst)
- return;
-
- s = str;
- n = count;
- x = efi_x;
-
- while (n-- > 0) {
- efi_earlycon_write_char(dst + x*4, *s, h);
- x += font->width;
- s++;
- }
-
- efi_earlycon_unmap(dst, len);
- }
-
- num -= count;
- efi_x += count * font->width;
- str += count;
-
- if (num > 0 && *s == '\n') {
- efi_x = 0;
- efi_y += font->height;
- str++;
- num--;
- }
-
- if (efi_x + font->width > si->lfb_width) {
- efi_x = 0;
- efi_y += font->height;
- }
-
- if (efi_y + font->height > si->lfb_height) {
- u32 i;
-
- efi_y -= font->height;
- efi_earlycon_scroll_up();
-
- for (i = 0; i < font->height; i++)
- efi_earlycon_clear_scanline(efi_y + i);
- }
- }
-}
-
-static int __init efi_earlycon_setup(struct earlycon_device *device,
- const char *opt)
-{
- struct screen_info *si;
- u16 xres, yres;
- u32 i;
-
- if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
- return -ENODEV;
-
- fb_base = screen_info.lfb_base;
- if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
- fb_base |= (u64)screen_info.ext_lfb_base << 32;
-
- fb_wb = opt && !strcmp(opt, "ram");
-
- si = &screen_info;
- xres = si->lfb_width;
- yres = si->lfb_height;
-
- /*
- * efi_earlycon_write_char() implicitly assumes a framebuffer with
- * 32 bits per pixel.
- */
- if (si->lfb_depth != 32)
- return -ENODEV;
-
- font = get_default_font(xres, yres, -1, -1);
- if (!font)
- return -ENODEV;
-
- efi_y = rounddown(yres, font->height) - font->height;
- for (i = 0; i < (yres - efi_y) / font->height; i++)
- efi_earlycon_scroll_up();
-
- device->con->write = efi_earlycon_write;
- earlycon_console = device->con;
- return 0;
-}
-EARLYCON_DECLARE(efifb, efi_earlycon_setup);
diff --git a/drivers/video/console/Kconfig b/drivers/video/console/Kconfig
index 40c50fa2dd70c33a1549141b15e6cba721352d2d..8052507e058fce37f5a51058e58ae2eb10d9669a 100644
--- a/drivers/video/console/Kconfig
+++ b/drivers/video/console/Kconfig
@@ -69,6 +69,17 @@ config DUMMY_CONSOLE_ROWS
monitor.
Select 25 if you use a 640x480 resolution by default.

+config FB_EARLYCON
+ bool "Generic framebuffer early console"
+ depends on SERIAL_EARLYCON && !ARM && !IA64
+ select FONT_SUPPORT
+ select ARCH_USE_MEMREMAP_PROT
+ help
+ Say Y here if you want early console support for firmware established
+ linear framebuffer. Unless you are using EFI framebuffer, you need to
+ specify framebuffer geometry and address in device-tree or in kernel
+ command line.
+
config FRAMEBUFFER_CONSOLE
bool "Framebuffer Console support"
depends on FB && !UML
diff --git a/drivers/video/console/Makefile b/drivers/video/console/Makefile
index db07b784bd2ccdcbffde933926ed5cee2bbbc7d4..7818faee587fc9c40b429617cfa224c0ccbc557c 100644
--- a/drivers/video/console/Makefile
+++ b/drivers/video/console/Makefile
@@ -9,4 +9,5 @@ obj-$(CONFIG_STI_CONSOLE) += sticon.o sticore.o
obj-$(CONFIG_VGA_CONSOLE) += vgacon.o
obj-$(CONFIG_MDA_CONSOLE) += mdacon.o

+obj-$(CONFIG_FB_EARLYCON) += earlycon.o
obj-$(CONFIG_FB_STI) += sticore.o
diff --git a/drivers/video/console/earlycon.c b/drivers/video/console/earlycon.c
new file mode 100644
index 0000000000000000000000000000000000000000..54436587e3db90034652dcc144669dca91b863d5
--- /dev/null
+++ b/drivers/video/console/earlycon.c
@@ -0,0 +1,305 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2013 Intel Corporation; author Matt Fleming
+ * Copyright (C) 2022 Markuss Broks <[email protected]>
+ */
+
+#include <asm/early_ioremap.h>
+#include <linux/console.h>
+#include <linux/efi.h>
+#include <linux/font.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/serial_core.h>
+#include <linux/screen_info.h>
+
+struct fb_earlycon {
+ u32 x, y, curr_x, curr_y, depth, stride;
+ size_t size;
+ phys_addr_t phys_base;
+ void __iomem *virt_base;
+};
+
+static const struct console *earlycon_console __initconst;
+static struct fb_earlycon info;
+static const struct font_desc *font;
+
+static int __init simplefb_earlycon_remap_fb(void)
+{
+ unsigned long mapping;
+ /* bail if there is no bootconsole or it has been disabled already */
+ if (!earlycon_console || !(earlycon_console->flags & CON_ENABLED))
+ return 0;
+
+ if (region_intersects(info.phys_base, info.size,
+ IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE) == REGION_INTERSECTS)
+ mapping = MEMREMAP_WB;
+ else
+ mapping = MEMREMAP_WC;
+
+ info.virt_base = memremap(info.phys_base, info.size, mapping);
+
+ return info.virt_base ? 0 : -ENOMEM;
+}
+early_initcall(simplefb_earlycon_remap_fb);
+
+static int __init simplefb_earlycon_unmap_fb(void)
+{
+ /* unmap the bootconsole fb unless keep_bootcon has left it enabled */
+ if (info.virt_base && !(earlycon_console->flags & CON_ENABLED))
+ memunmap(info.virt_base);
+ return 0;
+}
+late_initcall(simplefb_earlycon_unmap_fb);
+
+static __ref void *simplefb_earlycon_map(unsigned long start, unsigned long len)
+{
+ pgprot_t fb_prot;
+
+ if (info.virt_base)
+ return info.virt_base + start;
+
+ fb_prot = PAGE_KERNEL;
+ return early_memremap_prot(info.phys_base + start, len, pgprot_val(fb_prot));
+}
+
+static __ref void simplefb_earlycon_unmap(void *addr, unsigned long len)
+{
+ if (info.virt_base)
+ return;
+
+ early_memunmap(addr, len);
+}
+
+static void simplefb_earlycon_clear_scanline(unsigned int y)
+{
+ unsigned long *dst;
+ u16 len;
+
+ len = info.stride;
+ dst = simplefb_earlycon_map(y * len, len);
+ if (!dst)
+ return;
+
+ memset(dst, 0, len);
+ simplefb_earlycon_unmap(dst, len);
+}
+
+static void simplefb_earlycon_scroll_up(void)
+{
+ unsigned long *dst, *src;
+ u16 len;
+ u32 i, height;
+
+ len = info.stride;
+ height = info.y;
+
+ for (i = 0; i < height - font->height; i++) {
+ dst = simplefb_earlycon_map(i * len, len);
+ if (!dst)
+ return;
+
+ src = simplefb_earlycon_map((i + font->height) * len, len);
+ if (!src) {
+ simplefb_earlycon_unmap(dst, len);
+ return;
+ }
+
+ memmove(dst, src, len);
+
+ simplefb_earlycon_unmap(src, len);
+ simplefb_earlycon_unmap(dst, len);
+ }
+}
+
+static void simplefb_earlycon_write_char(u8 *dst, unsigned char c, unsigned int h)
+{
+ const u8 *src;
+ int m, n, bytes;
+ u8 x;
+
+ bytes = BITS_TO_BYTES(font->width);
+ src = font->data + c * font->height * bytes + h * bytes;
+
+ for (m = 0; m < font->width; m++) {
+ n = m % 8;
+ x = *(src + m / 8);
+ if ((x >> (7 - n)) & 1)
+ memset(dst, 0xff, (info.depth / 8));
+ else
+ memset(dst, 0, (info.depth / 8));
+ dst += (info.depth / 8);
+ }
+}
+
+static void
+simplefb_earlycon_write(struct console *con, const char *str, unsigned int num)
+{
+ unsigned int len;
+ const char *s;
+ void *dst;
+
+ len = info.stride;
+
+ while (num) {
+ unsigned int linemax;
+ unsigned int h, count = 0;
+
+ for (s = str; *s && *s != '\n'; s++) {
+ if (count == num)
+ break;
+ count++;
+ }
+
+ linemax = (info.x - info.curr_x) / font->width;
+ if (count > linemax)
+ count = linemax;
+
+ for (h = 0; h < font->height; h++) {
+ unsigned int n, x;
+
+ dst = simplefb_earlycon_map((info.curr_y + h) * len, len);
+ if (!dst)
+ return;
+
+ s = str;
+ n = count;
+ x = info.curr_x;
+
+ while (n-- > 0) {
+ simplefb_earlycon_write_char(dst + (x * 4), *s, h);
+ x += font->width;
+ s++;
+ }
+
+ simplefb_earlycon_unmap(dst, len);
+ }
+
+ num -= count;
+ info.curr_x += count * font->width;
+ str += count;
+
+ if (num > 0 && *s == '\n') {
+ info.curr_x = 0;
+ info.curr_y += font->height;
+ str++;
+ num--;
+ }
+
+ if (info.curr_x + font->width > info.x) {
+ info.curr_x = 0;
+ info.curr_y += font->height;
+ }
+
+ if (info.curr_y + font->height > info.y) {
+ u32 i;
+
+ info.curr_y -= font->height;
+ simplefb_earlycon_scroll_up();
+
+ for (i = 0; i < font->height; i++)
+ simplefb_earlycon_clear_scanline(info.curr_y + i);
+ }
+ }
+}
+
+static int __init simplefb_earlycon_setup_common(struct earlycon_device *device,
+ const char *opt)
+{
+ int i;
+
+ info.size = info.x * info.y * (info.depth / 8);
+
+ font = get_default_font(info.x, info.y, -1, -1);
+ if (!font)
+ return -ENODEV;
+
+ info.curr_y = rounddown(info.y, font->height) - font->height;
+ for (i = 0; i < (info.y - info.curr_y) / font->height; i++)
+ simplefb_earlycon_scroll_up();
+
+ device->con->write = simplefb_earlycon_write;
+ earlycon_console = device->con;
+ return 0;
+}
+
+static int __init simplefb_earlycon_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ struct uart_port *port = &device->port;
+ int ret;
+
+ if (!port->mapbase)
+ return -ENODEV;
+
+ info.phys_base = port->mapbase;
+
+ ret = sscanf(device->options, "%ux%ux%u", &info.x, &info.y, &info.depth);
+ if (ret != 3)
+ return -ENODEV;
+
+ info.stride = info.x * (info.depth / 8);
+
+ return simplefb_earlycon_setup_common(device, opt);
+}
+
+EARLYCON_DECLARE(simplefb, simplefb_earlycon_setup);
+
+#ifdef CONFIG_EFI_EARLYCON
+static int __init simplefb_earlycon_setup_efi(struct earlycon_device *device,
+ const char *opt)
+{
+ if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
+ return -ENODEV;
+
+ info.phys_base = screen_info.lfb_base;
+ if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
+ info.phys_base |= (u64)screen_info.ext_lfb_base << 32;
+
+ info.x = screen_info.lfb_width;
+ info.y = screen_info.lfb_height;
+ info.depth = screen_info.lfb_depth;
+ info.stride = screen_info.lfb_linelength;
+
+ return simplefb_earlycon_setup_common(device, opt);
+}
+
+EARLYCON_DECLARE(efifb, simplefb_earlycon_setup_efi);
+#endif
+
+#ifdef CONFIG_OF_EARLY_FLATTREE
+static int __init simplefb_earlycon_setup_of(struct earlycon_device *device,
+ const char *opt)
+{
+ struct uart_port *port = &device->port;
+ const __be32 *val;
+
+ if (!port->mapbase)
+ return -ENODEV;
+
+ info.phys_base = port->mapbase;
+
+ val = of_get_flat_dt_prop(device->offset, "width", NULL);
+ if (!val)
+ return -ENODEV;
+ info.x = be32_to_cpu(*val);
+
+ val = of_get_flat_dt_prop(device->offset, "height", NULL);
+ if (!val)
+ return -ENODEV;
+ info.y = be32_to_cpu(*val);
+
+ val = of_get_flat_dt_prop(device->offset, "stride", NULL);
+ if (!val)
+ return -ENODEV;
+ info.stride = be32_to_cpu(*val);
+ info.depth = (info.stride / info.x) * 8;
+
+ return simplefb_earlycon_setup_common(device, opt);
+}
+
+OF_EARLYCON_DECLARE(simplefb, "simple-framebuffer", simplefb_earlycon_setup_of);
+#endif
--
2.37.0

2022-08-06 17:23:49

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v2 1/3] drivers: serial: earlycon: Correct argument name

On Sat, Aug 6, 2022 at 6:37 PM Markuss Broks <[email protected]> wrote:
>
> The "node" argument is actually an offset, and it's also
> an "int", and not "unsigned long". Correct the of_setup_earlycon
> function.

Suggested-by: Greg KH?

> Signed-off-by: Markuss Broks <[email protected]>

--
With Best Regards,
Andy Shevchenko

2022-08-06 22:05:23

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v2 3/3] efi: earlycon: Add support for generic framebuffers and move to console subsystem

On Sat, Aug 6, 2022 at 6:38 PM Markuss Broks <[email protected]> wrote:
>
> Add early console support for generic linear framebuffer devices.
> This driver supports probing from cmdline early parameters
> or from the device-tree using information in simple-framebuffer node.
> The EFI functionality should be retained in whole.
> The driver was disabled on ARM because of a bug in early_ioremap

We refer to functions like func().

> implementation on ARM and on IA64 because of lack of early_memremap_prot.

Ditto.

...

> +#include <asm/early_ioremap.h>

Can it be placed after linux/* ones?

> +#include <linux/console.h>
> +#include <linux/efi.h>
> +#include <linux/font.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/mm.h>
> +#include <linux/of.h>
> +#include <linux/of_fdt.h>
> +#include <linux/serial_core.h>
> +#include <linux/screen_info.h>

...

> +static int __init simplefb_earlycon_remap_fb(void)
> +{
> + unsigned long mapping;

+ Blank line.

> + /* bail if there is no bootconsole or it has been disabled already */
> + if (!earlycon_console || !(earlycon_console->flags & CON_ENABLED))
> + return 0;
> +
> + if (region_intersects(info.phys_base, info.size,
> + IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE) == REGION_INTERSECTS)
> + mapping = MEMREMAP_WB;
> + else
> + mapping = MEMREMAP_WC;

> + info.virt_base = memremap(info.phys_base, info.size, mapping);
> +
> + return info.virt_base ? 0 : -ENOMEM;

Easier to read the standard pattern:

if (!info.virt_base)
return -ENOMEM;

return 0;

> +}

...

> +static void simplefb_earlycon_write_char(u8 *dst, unsigned char c, unsigned int h)
> +{
> + const u8 *src;
> + int m, n, bytes;
> + u8 x;
> +
> + bytes = BITS_TO_BYTES(font->width);
> + src = font->data + c * font->height * bytes + h * bytes;
> +
> + for (m = 0; m < font->width; m++) {
> + n = m % 8;
> + x = *(src + m / 8);

I would write it as

x = src[m / 8];

> + if ((x >> (7 - n)) & 1)

> + memset(dst, 0xff, (info.depth / 8));

Too many parentheses.

> + else
> + memset(dst, 0, (info.depth / 8));

Ditto.

> + dst += (info.depth / 8);

Ditto.

> + }
> +}

--
With Best Regards,
Andy Shevchenko

2022-08-07 13:42:51

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH v2 3/3] efi: earlycon: Add support for generic framebuffers and move to console subsystem

Hi Markuss,

I love your patch! Yet something to improve:

[auto build test ERROR on tty/tty-testing]
[also build test ERROR on efi/next staging/staging-testing usb/usb-testing linus/master v5.19 next-20220805]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Markuss-Broks/Add-generic-framebuffer-support-to-EFI-earlycon-driver/20220807-003646
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20220807/[email protected]/config)
compiler: sh4-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/97dfc2aa69b065de769a191352afe2099c52fedb
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Markuss-Broks/Add-generic-framebuffer-support-to-EFI-earlycon-driver/20220807-003646
git checkout 97dfc2aa69b065de769a191352afe2099c52fedb
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=sh SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <[email protected]>

All errors (new ones prefixed by >>):

>> drivers/video/console/earlycon.c:7:10: fatal error: asm/early_ioremap.h: No such file or directory
7 | #include <asm/early_ioremap.h>
| ^~~~~~~~~~~~~~~~~~~~~
compilation terminated.


vim +7 drivers/video/console/earlycon.c

> 7 #include <asm/early_ioremap.h>
8 #include <linux/console.h>
9 #include <linux/efi.h>
10 #include <linux/font.h>
11 #include <linux/io.h>
12 #include <linux/kernel.h>
13 #include <linux/mm.h>
14 #include <linux/of.h>
15 #include <linux/of_fdt.h>
16 #include <linux/serial_core.h>
17 #include <linux/screen_info.h>
18

--
0-DAY CI Kernel Test Service
https://01.org/lkp