soc/intel/common: Enable decoding of the COMB range to LPC based on Kconfig
By default all Intel platform has enable IO decode range for COMA if
CONFIG_DRIVERS_UART_8250IO is selected.
With this patch, COMB will get enable based on
CONFIG_SOC_INTEL_COMMON_BLOCK_LPC_COMB_ENABLE Kconfig selection.
Also make lpc_enable_fixed_io_ranges() function returns Enabled I/O bits to avoid
an additional pci configuration read to get the same data.
Change-Id: I884dbcc8a37cf8551001d0ca61910c986b903ebc
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/25045
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Rizwan Qureshi <rizwan.qureshi@intel.com>
diff --git a/src/soc/intel/common/block/lpc/lpc_lib.c b/src/soc/intel/common/block/lpc/lpc_lib.c
index b4b3d1b..aeac441 100644
--- a/src/soc/intel/common/block/lpc/lpc_lib.c
+++ b/src/soc/intel/common/block/lpc/lpc_lib.c
@@ -1,7 +1,7 @@
/*
* This file is part of the coreboot project.
*
- * Copyright (C) 2016 Intel Corp.
+ * Copyright (C) 2016-2018 Intel Corp.
* (Written by Alexandru Gagniuc <alexandrux.gagniuc@intel.com> for Intel Corp.)
*
* This program is free software; you can redistribute it and/or modify
@@ -25,13 +25,15 @@
#include "lpc_def.h"
#include <soc/pci_devs.h>
-void lpc_enable_fixed_io_ranges(uint16_t io_enables)
+uint16_t lpc_enable_fixed_io_ranges(uint16_t io_enables)
{
uint16_t reg_io_enables;
reg_io_enables = pci_read_config16(PCH_DEV_LPC, LPC_IO_ENABLES);
io_enables |= reg_io_enables;
pci_write_config16(PCH_DEV_LPC, LPC_IO_ENABLES, io_enables);
+
+ return io_enables;
}
/*
@@ -225,15 +227,20 @@
void lpc_io_setup_comm_a_b(void)
{
- /*
- * Setup I/O Decode Range Register for LPC
- * ComA Range 3F8h-3FFh [2:0]
- * ComB Range 2F8h-2FFh [6:4]
- */
- pci_write_config16(PCH_DEV_LPC, LPC_IO_DECODE,
- LPC_IOD_COMA_RANGE | LPC_IOD_COMB_RANGE);
+ /* ComA Range 3F8h-3FFh [2:0] */
+ uint16_t com_ranges = LPC_IOD_COMA_RANGE;
+ uint16_t com_enable = LPC_IOE_COMA_EN;
+
+ /* ComB Range 2F8h-2FFh [6:4] */
+ if (IS_ENABLED(CONFIG_SOC_INTEL_COMMON_BLOCK_LPC_COMB_ENABLE)) {
+ com_ranges |= LPC_IOD_COMB_RANGE;
+ com_enable |= LPC_IOE_COMB_EN;
+ }
+
+ /* Setup I/O Decode Range Register for LPC */
+ pci_write_config16(PCH_DEV_LPC, LPC_IO_DECODE, com_ranges);
/* Enable ComA and ComB Port */
- lpc_enable_fixed_io_ranges(LPC_IOE_COMA_EN | LPC_IOE_COMB_EN);
+ lpc_enable_fixed_io_ranges(com_enable);
}
static void lpc_set_gen_decode_range(