Change in coreboot[master]: soc/intel/lpc_lib: mirror LPC registers to DMI when required

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/49592 )

Change subject: soc/intel/lpc_lib: mirror LPC registers to DMI when required
......................................................................

soc/intel/lpc_lib: mirror LPC registers to DMI when required

Starting with SPT, LPC registers IOD, IOE, LGIR* and LGMR need to be
mirrored to their corresponding DMI registers. Add the required writes
to DMI registers, where the PCI config registers get written.

This is already done in soc code for IOD, IOE and LGIR* by mirroring
the registers later, during PCH init. Also the code mostly matches
accross the platforms. This common implementation will avoid delayed
mirroring of the registers and also deduplicate the code.

This change also adds a new Kconfig that will be selected by platforms
requiring mirroring of LPC IO/MMIO registers to their corresponding DMI
registers.

For making use of this common code, the redundant soc code needs to be
dropped and the newly introduced Kconfig option has to be selected. This
is done in the follow-up change.

Change-Id: I39f3bf4c486a1bbc112b2b453381de6da4bbac4d
Signed-off-by: Michael Niewöhner 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49592
Tested-by: build bot (Jenkins) 
Reviewed-by: Nico Huber 
---
M src/soc/intel/common/block/include/intelblocks/lpc_lib.h
M src/soc/intel/common/block/lpc/Kconfig
M src/soc/intel/common/block/lpc/lpc_def.h
M src/soc/intel/common/block/lpc/lpc_lib.c
4 files changed, 31 insertions(+), 6 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Nico Huber: Looks good to me, approved

diff --git a/src/soc/intel/common/block/include/intelblocks/lpc_lib.h b/src/soc/intel/common/block/include/intelblocks/lpc_lib.h
index bf5c2f6..c5842d5 100644
--- a/src/soc/intel/common/block/include/intelblocks/lpc_lib.h
+++ b/src/soc/intel/common/block/include/intelblocks/lpc_lib.h
@@ -30,6 +30,8 @@
 #define PCR_DMI_LPCLGIR3		0x2738
 #define PCR_DMI_LPCLGIR4		0x273c

+#define PCR_DMI_LPCGMR			0x2740
+
 #define PCR_DMI_LPCIOD			0x2770
 #define PCR_DMI_LPCIOE			0x2774

diff --git a/src/soc/intel/common/block/lpc/Kconfig b/src/soc/intel/common/block/lpc/Kconfig
index 41e72c4..d76620a 100644
--- a/src/soc/intel/common/block/lpc/Kconfig
+++ b/src/soc/intel/common/block/lpc/Kconfig
@@ -11,3 +11,10 @@
    help
      By default COMA range to LPC is enable. COMB range to LPC is optional
      and should select based on platform dedicated selection.
+
+config SOC_INTEL_COMMON_BLOCK_LPC_MIRROR_TO_DMI
+	bool
+	depends on SOC_INTEL_COMMON_BLOCK_DMI
+	help
+	  Mirror LPC registers for IO/MMIO to their corresponding DMI registers.
+	  Required for platforms starting from SPT.
diff --git a/src/soc/intel/common/block/lpc/lpc_def.h b/src/soc/intel/common/block/lpc/lpc_def.h
index 7753169..ab9f201 100644
--- a/src/soc/intel/common/block/lpc/lpc_def.h
+++ b/src/soc/intel/common/block/lpc/lpc_def.h
@@ -7,8 +7,10 @@
 #define  LPC_SCNT_EN			(1 << 7)
 #define  LPC_SCNT_MODE			(1 << 6)
 #define LPC_IO_DECODE			0x80
-#define  LPC_IOD_COMA_RANGE             (0 << 0) /* 0x3F8 - 0x3FF COMA*/
-#define  LPC_IOD_COMB_RANGE             (1 << 4) /* 0x2F8 - 0x2FF COMB*/
+#define  LPC_IOD_COMA_RANGE_MASK	(7 << 0)
+#define  LPC_IOD_COMB_RANGE_MASK	(7 << 4)
+#define  LPC_IOD_COMA_RANGE		(0 << 0) /* 0x3F8 - 0x3FF COMA */
+#define  LPC_IOD_COMB_RANGE		(1 << 4) /* 0x2F8 - 0x2FF COMB */
 /* Use IO_<peripheral>_<IO port> style macros defined in lpc_lib.h
  * to enable decoding of I/O locations for a peripheral. */
 #define LPC_IO_ENABLES			0x82
diff --git a/src/soc/intel/common/block/lpc/lpc_lib.c b/src/soc/intel/common/block/lpc/lpc_lib.c
index 28c435c..242d7d9 100644
--- a/src/soc/intel/common/block/lpc/lpc_lib.c
+++ b/src/soc/intel/common/block/lpc/lpc_lib.c
@@ -9,10 +9,12 @@
 #include <device/pci_ops.h>
 #include <intelblocks/itss.h>
 #include <intelblocks/lpc_lib.h>
+#include <intelblocks/pcr.h>
 #include <lib.h>
 #include "lpc_def.h"
 #include <soc/irq.h>
 #include <soc/pci_devs.h>
+#include <soc/pcr_ids.h>

uint16_t lpc_enable_fixed_io_ranges(uint16_t io_enables)
 {
@@ -21,6 +23,8 @@
    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);
+	if (CONFIG(SOC_INTEL_COMMON_BLOCK_LPC_MIRROR_TO_DMI))
+		pcr_write16(PID_DMI, PCR_DMI_LPCIOE, io_enables);

return io_enables;
 }
@@ -37,6 +41,8 @@
    reg_io_ranges = lpc_get_fixed_io_decode() & ~mask;
    io_ranges |= reg_io_ranges & mask;
    pci_write_config16(PCH_DEV_LPC, LPC_IO_DECODE, io_ranges);
+	if (CONFIG(SOC_INTEL_COMMON_BLOCK_LPC_MIRROR_TO_DMI))
+		pcr_write16(PID_DMI, PCR_DMI_LPCIOD, io_ranges);

return io_ranges;
 }
@@ -105,6 +111,8 @@
    	lgir_reg_offset = LPC_GENERIC_IO_RANGE(lgir_reg_num);

pci_write_config32(PCH_DEV_LPC, lgir_reg_offset, lgir);
+		if (CONFIG(SOC_INTEL_COMMON_BLOCK_LPC_MIRROR_TO_DMI))
+			pcr_write32(PID_DMI, PCR_DMI_LPCLGIR1 + lgir_reg_num * 4, lgir);

printk(BIOS_DEBUG,
    	       "LPC: Opened IO window LGIR%d: base %llx size %x\n",
@@ -138,6 +146,8 @@
    lgmr = (base & LPC_LGMR_ADDR_MASK) | LPC_LGMR_EN;

pci_write_config32(PCH_DEV_LPC, LPC_GENERIC_MEM_RANGE, lgmr);
+	if (CONFIG(SOC_INTEL_COMMON_BLOCK_LPC_MIRROR_TO_DMI))
+		pcr_write32(PID_DMI, PCR_DMI_LPCGMR, lgmr);
 }

/*
@@ -214,15 +224,17 @@
    /* ComA Range 3F8h-3FFh [2:0] */
    uint16_t com_ranges = LPC_IOD_COMA_RANGE;
    uint16_t com_enable = LPC_IOE_COMA_EN;
+	uint16_t com_mask   = LPC_IOD_COMA_RANGE_MASK;

/* ComB Range 2F8h-2FFh [6:4] */
    if (CONFIG(SOC_INTEL_COMMON_BLOCK_LPC_COMB_ENABLE)) {
    	com_ranges |= LPC_IOD_COMB_RANGE;
    	com_enable |= LPC_IOE_COMB_EN;
+		com_mask   |= LPC_IOD_COMB_RANGE_MASK;
    }

/* Setup I/O Decode Range Register for LPC */
-	pci_write_config16(PCH_DEV_LPC, LPC_IO_DECODE, com_ranges);
+	lpc_set_fixed_io_ranges(com_ranges, com_mask);
    /* Enable ComA and ComB Port */
    lpc_enable_fixed_io_ranges(com_enable);
 }
@@ -233,9 +245,11 @@
    size_t i;

/* Set in PCI generic decode range registers */
-	for (i = 0; i < LPC_NUM_GENERIC_IO_RANGES; i++)
-		pci_write_config32(PCH_DEV_LPC, LPC_GENERIC_IO_RANGE(i),
-			gen_io_dec[i]);
+	for (i = 0; i < LPC_NUM_GENERIC_IO_RANGES; i++) {
+		pci_write_config32(PCH_DEV_LPC, LPC_GENERIC_IO_RANGE(i), gen_io_dec[i]);
+		if (CONFIG(SOC_INTEL_COMMON_BLOCK_LPC_MIRROR_TO_DMI))
+			pcr_write32(PID_DMI, PCR_DMI_LPCLGIR1 + i * 4, gen_io_dec[i]);
+	}
 }

void pch_enable_lpc(void)