From 138c1b864bf9745f084e2b7035204aaa3b5b983c Mon Sep 17 00:00:00 2001 From: Paul Menzel Date: Mon, 12 Oct 2020 01:29:12 +0200 Subject: superio/nuvoton: Only set bit 7 of global CR 0x2a for COM A Currently, when selecting SUPERIO_NUVOTON_NCT*_COM_A, the whole global control register 0x2a is written to 0x40. CR 0x2a defaults to 0xc0, so indeed bit 7 is cleared, but the device early init code might have set other bits in that control register, so setting it to 0x40 might override already set bits. So, only clear bit 7 and leave the other bits untouched. Fixes: f95daa510d ("superio/nuvoton: Add back Nuvoton NCT6776 support") Change-Id: I9ded9dab3985c4c8e5c45af354ef44af482e18c2 Signed-off-by: Paul Menzel Reviewed-on: https://review.coreboot.org/c/coreboot/+/46286 Tested-by: build bot (Jenkins) Reviewed-by: Angel Pons Reviewed-by: Nico Huber --- src/superio/nuvoton/common/early_serial.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/superio/nuvoton/common/early_serial.c b/src/superio/nuvoton/common/early_serial.c index cc21f40d2a..ed5fdbab1f 100644 --- a/src/superio/nuvoton/common/early_serial.c +++ b/src/superio/nuvoton/common/early_serial.c @@ -55,7 +55,7 @@ void nuvoton_enable_serial(pnp_devfn_t dev, u16 iobase) if (CONFIG(SUPERIO_NUVOTON_NCT5539D_COM_A) || CONFIG(SUPERIO_NUVOTON_NCT6776_COM_A)) /* Route COM A to GPIO8 pin group */ - pnp_write_config(dev, 0x2a, 0x40); + pnp_unset_and_set_config(dev, 0x2a, 1 << 7, 0); if (CONFIG(SUPERIO_NUVOTON_NCT6791D_COM_A)) /* Route COM A to GPIO8 pin group */ -- cgit v1.2.3