leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

tty: serial: samsung_tty: Add earlycon support for Apple UARTs

Browse Source 
Earlycon support is identical to S3C2410, but Apple SoCs also need
MMIO mapped as nGnRnE. This is handled generically for normal drivers
including the normal UART path here, but earlycon uses fixmap and
runs before that scaffolding is ready.

Since this is the only case where we need this fix, it makes more
sense to do it here in the UART driver instead of introducing a
whole fdt nonposted-mmio resolver just for earlycon/fixmap.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hector Martin <marcan@marcan.st>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210304213902.83903-26-marcan@marcan.st
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Hector Martin 2021-03-05 06:39:00 +09:00 committed by Greg Kroah-Hartman
parent fcbba34490
commit b89cfc05a2
1 changed files with 17 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
drivers/tty/serial/samsung_tty.c
View File

@ -3001,6 +3001,23 @@ OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
s5pv210_early_console_setup);
OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
s5pv210_early_console_setup);
/* Apple S5L */
static int __init apple_s5l_early_console_setup(struct earlycon_device *device,
const char *opt)
{
/* Close enough to S3C2410 for earlycon... */
device->port.private_data = &s3c2410_early_console_data;
#ifdef CONFIG_ARM64
/* ... but we need to override the existing fixmap entry as nGnRnE */
__set_fixmap(FIX_EARLYCON_MEM_BASE, device->port.mapbase,
__pgprot(PROT_DEVICE_nGnRnE));
#endif
return samsung_early_console_setup(device, opt);
}
OF_EARLYCON_DECLARE(s5l, "apple,s5l-uart", apple_s5l_early_console_setup);
#endif
MODULE_ALIAS("platform:samsung-uart");