[U-Boot] [PATCH v5 091/101] x86: apl: Add LPC driver
Simon Glass
sjg at chromium.org
Mon Nov 25 04:10:41 UTC 2019
This driver the LPC and provides a few functions to set up LPC features.
These should probably use ioctls() or perhaps, better, have specific
uclass methods.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v5: None
Changes in v4:
- Add comments for exported functions
- Tidy up header guards
- Use 'Apollo Lake'
- Use BIT() macro a bit more
- Use tabs instead of spaces
Changes in v3:
- Drop unused code in lpc_configure_pads()
- Fix value of LPC_BC_LE
Changes in v2: None
arch/x86/cpu/apollolake/Makefile | 1 +
arch/x86/cpu/apollolake/lpc.c | 141 +++++++++++++++++++++
arch/x86/include/asm/arch-apollolake/lpc.h | 82 ++++++++++++
3 files changed, 224 insertions(+)
create mode 100644 arch/x86/cpu/apollolake/lpc.c
create mode 100644 arch/x86/include/asm/arch-apollolake/lpc.h
diff --git a/arch/x86/cpu/apollolake/Makefile b/arch/x86/cpu/apollolake/Makefile
index 2d78368150..31045a03c1 100644
--- a/arch/x86/cpu/apollolake/Makefile
+++ b/arch/x86/cpu/apollolake/Makefile
@@ -6,5 +6,6 @@ obj-$(CONFIG_SPL_BUILD) += systemagent.o
obj-y += hostbridge.o
obj-y += itss.o
+obj-y += lpc.o
obj-y += pmc.o
obj-y += uart.o
diff --git a/arch/x86/cpu/apollolake/lpc.c b/arch/x86/cpu/apollolake/lpc.c
new file mode 100644
index 0000000000..b14eed6508
--- /dev/null
+++ b/arch/x86/cpu/apollolake/lpc.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Google LLC
+ *
+ * From coreboot Apollo Lake support lpc.c
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <spl.h>
+#include <asm/lpc_common.h>
+#include <asm/pci.h>
+#include <asm/arch/iomap.h>
+#include <asm/arch/lpc.h>
+#include <linux/log2.h>
+
+void lpc_configure_pads(void)
+{
+ /* All pads are configured by the hostbridge */
+}
+
+void lpc_enable_fixed_io_ranges(uint io_enables)
+{
+ pci_x86_clrset_config(PCH_DEV_LPC, LPC_IO_ENABLES, 0, io_enables,
+ PCI_SIZE_16);
+}
+
+/*
+ * Find the first unused IO window.
+ * Returns -1 if not found, 0 for reg 0x84, 1 for reg 0x88 ...
+ */
+static int find_unused_pmio_window(void)
+{
+ int i;
+ ulong lgir;
+
+ for (i = 0; i < LPC_NUM_GENERIC_IO_RANGES; i++) {
+ pci_x86_read_config(PCH_DEV_LPC, LPC_GENERIC_IO_RANGE(i),
+ &lgir, PCI_SIZE_32);
+
+ if (!(lgir & LPC_LGIR_EN))
+ return i;
+ }
+
+ return -1;
+}
+
+int lpc_open_pmio_window(uint base, uint size)
+{
+ int i, lgir_reg_num;
+ u32 lgir_reg_offset, lgir, window_size, alignment;
+ ulong bridged_size, bridge_base;
+ ulong reg;
+
+ log_debug("LPC: Trying to open IO window from %x size %x\n", base,
+ size);
+
+ bridged_size = 0;
+ bridge_base = base;
+
+ while (bridged_size < size) {
+ /* Each IO range register can only open a 256-byte window */
+ window_size = min(size, (uint)LPC_LGIR_MAX_WINDOW_SIZE);
+
+ /* Window size must be a power of two for the AMASK to work */
+ alignment = 1UL << (order_base_2(window_size));
+ window_size = ALIGN(window_size, alignment);
+
+ /* Address[15:2] in LGIR[15:12] and Mask[7:2] in LGIR[23:18] */
+ lgir = (bridge_base & LPC_LGIR_ADDR_MASK) | LPC_LGIR_EN;
+ lgir |= ((window_size - 1) << 16) & LPC_LGIR_AMASK_MASK;
+
+ /* Skip programming if same range already programmed */
+ for (i = 0; i < LPC_NUM_GENERIC_IO_RANGES; i++) {
+ pci_x86_read_config(PCH_DEV_LPC,
+ LPC_GENERIC_IO_RANGE(i), ®,
+ PCI_SIZE_32);
+ if (lgir == reg)
+ return -EALREADY;
+ }
+
+ lgir_reg_num = find_unused_pmio_window();
+ if (lgir_reg_num < 0) {
+ log_err("LPC: Cannot open IO window: %lx size %lx\n",
+ bridge_base, size - bridged_size);
+ log_err("No more IO windows\n");
+
+ return -ENOSPC;
+ }
+ lgir_reg_offset = LPC_GENERIC_IO_RANGE(lgir_reg_num);
+
+ pci_x86_write_config(PCH_DEV_LPC, lgir_reg_offset, lgir,
+ PCI_SIZE_32);
+
+ log_debug("LPC: Opened IO window LGIR%d: base %lx size %x\n",
+ lgir_reg_num, bridge_base, window_size);
+
+ bridged_size += window_size;
+ bridge_base += window_size;
+ }
+
+ return 0;
+}
+
+void lpc_io_setup_comm_a_b(void)
+{
+ /* ComA Range 3F8h-3FFh [2:0] */
+ u16 com_ranges = LPC_IOD_COMA_RANGE;
+ u16 com_enable = LPC_IOE_COMA_EN;
+
+ /* ComB Range 2F8h-2FFh [6:4] */
+ if (0) {
+ 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(com_enable);
+}
+
+static int apl_lpc_probe(struct udevice *dev)
+{
+ if (spl_phase() == PHASE_TPL)
+ lpc_configure_pads();
+
+ return 0;
+}
+
+static const struct udevice_id apl_lpc_ids[] = {
+ { .compatible = "intel,apl-lpc" },
+ { }
+};
+
+U_BOOT_DRIVER(apl_lpc_drv) = {
+ .name = "intel_apl_lpc",
+ .id = UCLASS_LPC,
+ .of_match = apl_lpc_ids,
+ .probe = apl_lpc_probe,
+};
diff --git a/arch/x86/include/asm/arch-apollolake/lpc.h b/arch/x86/include/asm/arch-apollolake/lpc.h
new file mode 100644
index 0000000000..5d2adad319
--- /dev/null
+++ b/arch/x86/include/asm/arch-apollolake/lpc.h
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2017 Intel Corporation.
+ * Take from coreboot project file of the same name
+ */
+
+#ifndef _ASM_ARCH_LPC_H
+#define _ASM_ARCH_LPC_H
+
+#define LPC_SERIRQ_CTL 0x64
+#define LPC_SCNT_EN BIT(7)
+#define LPC_SCNT_MODE BIT(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*/
+/*
+ * 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
+#define LPC_GENERIC_IO_RANGE(n) ((((n) & 0x3) * 4) + 0x84)
+#define LPC_LGIR_AMASK_MASK (0xfc << 16)
+#define LPC_LGIR_ADDR_MASK 0xfffc
+#define LPC_LGIR_EN BIT(0)
+#define LPC_LGIR_MAX_WINDOW_SIZE 256
+#define LPC_GENERIC_MEM_RANGE 0x98
+#define LPC_LGMR_ADDR_MASK 0xffff0000
+#define LPC_LGMR_EN BIT(0)
+#define LPC_LGMR_WINDOW_SIZE (64 * KiB)
+#define LPC_BIOS_CNTL 0xdc
+#define LPC_BC_BILD BIT(7)
+#define LPC_BC_LE BIT(1)
+#define LPC_BC_EISS BIT(5)
+#define LPC_PCCTL 0xE0 /* PCI Clock Control */
+#define LPC_PCCTL_CLKRUN_EN BIT(0)
+
+/*
+ * IO decode enable macros are in the format IO_<peripheral>_<IO port>.
+ * For example, to open ports 0x60, 0x64 for the keyboard controller,
+ * use IOE_KBC_60_64 macro. For IOE_ macros that do not specify a port range,
+ * the port range is selectable via the IO decodes register.
+ */
+#define LPC_IOE_EC_4E_4F BIT(13)
+#define LPC_IOE_SUPERIO_2E_2F BIT(12)
+#define LPC_IOE_EC_62_66 BIT(11)
+#define LPC_IOE_KBC_60_64 BIT(10)
+#define LPC_IOE_HGE_208 BIT(9)
+#define LPC_IOE_LGE_200 BIT(8)
+#define LPC_IOE_FDD_EN BIT(3)
+#define LPC_IOE_LPT_EN BIT(2)
+#define LPC_IOE_COMB_EN BIT(1)
+#define LPC_IOE_COMA_EN BIT(0)
+#define LPC_NUM_GENERIC_IO_RANGES 4
+
+#define LPC_IO_ENABLES 0x82
+
+/**
+ * lpc_enable_fixed_io_ranges() - enable the fixed I/O ranges
+ *
+ * @io_enables: Mask of things to enable (LPC_IOE_.)
+ */
+void lpc_enable_fixed_io_ranges(uint io_enables);
+
+/**
+ * lpc_open_pmio_window() - Open an IO port range
+ *
+ * @base: Base I/O address (e.g. 0x800)
+ * @size: Size of window (e.g. 0x100)
+ * @return 0 if OK, -ENOSPC if there are no more windows available, -EALREADY
+ * if already set up
+ */
+int lpc_open_pmio_window(uint base, uint size);
+
+/**
+ * lpc_io_setup_comm_a_b() - Set up basic serial UARTs
+ *
+ * Set up the LPC to handle I/O to the COMA/COMB serial UART addresses
+ * 2f8-2ff and 3f8-3ff.
+ */
+void lpc_io_setup_comm_a_b(void);
+
+#endif
--
2.24.0.432.g9d3f5f5b63-goog
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