| Message ID | 20210304213902.83903-26-marcan@marcan.st (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Apple M1 SoC platform bring-up | expand |
On 04/03/2021 22:39, Hector Martin wrote: > 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> > --- > drivers/tty/serial/samsung_tty.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Best regards, Krzysztof
On Thu, Mar 4, 2021 at 10:42 PM Hector Martin <marcan@marcan.st> wrote: > 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> This is as elegant as it gets! Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Yours, Linus Walleij
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index 5ef37c4538ce..80df842bf4c7 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -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");
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> --- drivers/tty/serial/samsung_tty.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)