soc/intel/quark: Add legacy SPI flash controller driver

Add SPI driver code for the legacy SPI flash controller.  Enable erase
and write support allowing coreboot to save non-volatile data into
the SPI flash.

TEST=Build and run on Galileo Gen2.

Change-Id: I8f38c955d7c42a1e58728c728d0cecc36556de5c
Signed-off-by: Lee Leahy <Leroy.P.Leahy@intel.com>
Reviewed-on: https://review.coreboot.org/20231
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>

1 files changed, 301 insertions, 0 deletions

diff --git a/src/soc/intel/quark/spi.c b/src/soc/intel/quark/spi.c
new file mode 100644
index 0000000000..1d257a563e
--- /dev/null
+++ b/src/soc/intel/quark/spi.c
@@ -0,0 +1,301 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2017 Intel Corporation.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2 of
+ * the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <arch/io.h>
+#include <assert.h>
+#include <bootstate.h>
+#include <console/console.h>
+#include <device/pci_ids.h>
+#include <device/pci_def.h>
+#include <delay.h>
+#include <soc/pci_devs.h>
+#include <soc/QuarkNcSocId.h>
+#include <soc/spi.h>
+
+struct spi_context spi_driver_context = {
+	NULL,
+	0,
+	0
+};
+
+void spi_bios_base(uint32_t bios_base_address)
+{
+	uint32_t address;
+	volatile struct flash_ctrlr *ctrlr = spi_driver_context.ctrlr;
+
+	/* Prevent all SPI operations below this address */
+	address = 0xff000000 | bios_base_address;
+	ctrlr->bbar = address;
+}
+
+void spi_controller_lock(void)
+{
+	volatile struct flash_ctrlr *ctrlr = spi_driver_context.ctrlr;
+
+	/* Prevent BIOS and system from changing the SPI controller setup */
+	ctrlr->status |= SPISTS_CLD;
+}
+
+int spi_protection(uint32_t address, uint32_t length)
+{
+	uint32_t base;
+	volatile struct flash_ctrlr *ctrlr = spi_driver_context.ctrlr;
+	int index;
+	uint32_t limit;
+	uint32_t protect;
+	uint32_t value;
+
+	/* Determine the protection range */
+	base = address;
+	limit = address + length - 1;
+	protect = SPIPBR_WPE | (limit & SPIPBR_PRL)
+		| ((base >> SPIPBR_PRB_SHIFT) & SPIPBR_PRB);
+
+	/* Walk the list of protected areas */
+	for (index = 0; index < ARRAY_SIZE(ctrlr->pbr); index++) {
+		value = read32(&ctrlr->pbr[index]);
+
+		/* Don't duplicate if the range is already protected */
+		if (value == protect)
+			return 0;
+
+		/* Use the first free register to protect this range */
+		if ((value & SPIPBR_WPE) == 0) {
+			write32(&ctrlr->pbr[index], protect);
+			return 0;
+		}
+	}
+
+	/* No free protection range registers */
+	printk(BIOS_ERR,
+		"Failed to set protection: 0x%08x - 0x%08x, PRRs full!\n",
+				address, address + length - 1);
+	return -1;
+}
+
+static int xfer(const struct spi_slave *slave, const void *dout,
+	size_t bytesout, void *din, size_t bytesin)
+{
+	struct spi_context *context;
+	uint16_t control;
+	volatile struct flash_ctrlr *ctrlr;
+	uint8_t *data;
+	int index;
+	uint8_t opcode;
+	uint32_t status;
+	int type;
+
+	/* Locate the context structure */
+	context = &spi_driver_context;
+	ctrlr = context->ctrlr;
+
+	/* Validate the buffer sizes */
+	if (bytesin > sizeof(ctrlr->data)) {
+		printk(BIOS_ERR, "bytesin > %ld\n", sizeof(ctrlr->data));
+		goto error;
+	}
+
+	if (bytesin && (din == NULL)) {
+		printk(BIOS_ERR, "din is NULL\n");
+		goto error;
+	}
+
+	if (bytesout == 0) {
+		/* Check for a read operation */
+		if (bytesin == 0) {
+			printk(BIOS_ERR, "bytesout and bytesin == 0\n");
+			goto error;
+		}
+
+		/* Issue the read operation */
+		control = context->control;
+		control |= SPICTL_DC | ((bytesin - 1) << SPICTL_DBCNT_SHIFT);
+		goto start_cycle;
+	}
+
+	/* Locate the opcode in the opcode table */
+	data = (uint8_t *)dout;
+	opcode = *data++;
+	bytesout -= 1;
+	for (index = 0; index < sizeof(ctrlr->opmenu); index++)
+		if (opcode == ctrlr->opmenu[index])
+			break;
+
+	/* Check for a prefix byte */
+	if (index == sizeof(ctrlr->opmenu)) {
+		for (index = 0; index < sizeof(ctrlr->prefix); index++)
+			if (opcode == ctrlr->prefix[index])
+				break;
+
+		/* Handle the unknown opcode error */
+		if (index == sizeof(ctrlr->prefix)) {
+			printk(BIOS_ERR, "Unknown SPI flash opcode\n");
+			goto error;
+		}
+
+		/* Save the index for the next operation */
+		context->prefix = index;
+		return 0;
+	}
+
+	/* Get the opcode type */
+	type = (ctrlr->type >> (index * 2))
+		& (SPITYPE_ADDRESS | SPITYPE_PREFIX);
+
+	/* Determine if the opcode has an address */
+	if (type & SPITYPE_ADDRESS) {
+		if (bytesout < 3) {
+			printk(BIOS_ERR, "Missing address bytes\n");
+			goto error;
+		}
+
+		/* Use chip select 0 */
+		ctrlr->address = (data[0] << 16)
+			       | (data[1] << 8)
+			       |  data[2];
+		status = ctrlr->address;
+		data += 3;
+		bytesout -= 3;
+	}
+
+	/* Build the control value */
+	control = (index << SPICTL_COPTR_SHIFT)
+		| (context->prefix << SPICTL_SOPTR_SHIFT)
+		| SPICTL_CG | SPICTL_AR;
+	if (bytesout) {
+		memcpy((void *)&ctrlr->data[0], data, bytesout);
+		control |= SPICTL_DC | ((bytesout - 1) << SPICTL_DBCNT_SHIFT);
+	}
+
+	/* Save the control value for the read operation request */
+	if (!(type & SPITYPE_PREFIX)) {
+		context->control = control;
+		return 0;
+	}
+
+	/* Write operations require a prefix */
+	control |= SPICTL_ACS;
+
+start_cycle:
+	/* Start the SPI cycle */
+	ctrlr->control = control;
+	status = ctrlr->control;
+	context->prefix = 0;
+
+	/* Wait for the access to complete */
+	while ((status = ctrlr->status) & SPISTS_CIP)
+		udelay(1);
+
+	/* Clear any errors */
+	ctrlr->status = status;
+
+	/* Handle the blocked access error */
+	if (status & SPISTS_BA) {
+		printk(BIOS_ERR, "SPI access blocked!\n");
+		return -1;
+	}
+
+	/* Check for done */
+	if (status & SPISTS_CD) {
+		/* Return any receive data */
+		if (bytesin)
+			memcpy(din, (void *)&ctrlr->data[0], bytesin);
+		return 0;
+	}
+
+	/* Handle the timeout error */
+	printk(BIOS_ERR, "SPI transaction timeout!\n");
+
+error:
+	context->prefix = 0;
+	return -1;
+}
+
+void spi_init(void)
+{
+	uint32_t bios_control;
+	struct spi_context *context;
+	volatile struct flash_ctrlr *ctrlr;
+	device_t dev;
+	uint32_t rcba;
+
+	/* Determine the base address of the SPI flash controller */
+	context = &spi_driver_context;
+	dev = dev_find_device(PCI_VENDOR_ID_INTEL, LPC_DEVID, NULL);
+	rcba = pci_read_config32(dev, R_QNC_LPC_RCBA);
+	if (!(rcba & B_QNC_LPC_RCBA_EN)) {
+		printk(BIOS_ERR, "RBCA not enabled\n");
+		return;
+	}
+	rcba &= B_QNC_LPC_RCBA_MASK;
+	ctrlr = (volatile struct flash_ctrlr *)rcba;
+
+	/* Enable writes to the SPI flash */
+	bios_control = pci_read_config32(dev, R_QNC_LPC_BIOS_CNTL);
+	bios_control |= B_QNC_LPC_BIOS_CNTL_BIOSWE;
+	pci_write_config32(dev, R_QNC_LPC_BIOS_CNTL, bios_control);
+
+	/* Setup the SPI flash controller */
+	context->ctrlr = ctrlr;
+	ctrlr->opmenu[0] = 0x03;	/* Read */
+	ctrlr->opmenu[1] = 0x0b;	/* Read fast */
+	ctrlr->opmenu[2] = 0x05;	/* Read status */
+	ctrlr->opmenu[3] = 0x9f;	/* Read ID */
+	ctrlr->opmenu[4] = 0x02;	/* Page program */
+	ctrlr->opmenu[5] = 0x20;	/* Erase 4 KiB */
+	ctrlr->opmenu[6] = 0xd8;	/* Erase 64 KiB */
+	ctrlr->opmenu[7] = 0x01;	/* Write status */
+	ctrlr->prefix[0] = 0x50;	/* Write status enable */
+	ctrlr->prefix[1] = 0x06;	/* Write enable */
+	ctrlr->type = SPITYPE_ADDRESS                        /* Read */
+		| (SPITYPE_ADDRESS << 2)                     /* Read fast */
+		| (0 << 4)                                   /* Read status */
+		| (0 << 6)                                   /* Read ID */
+		| ((SPITYPE_ADDRESS | SPITYPE_PREFIX) << 8)  /* Page program */
+		| ((SPITYPE_ADDRESS | SPITYPE_PREFIX) << 10) /* Erase 4 KiB */
+		| ((SPITYPE_ADDRESS | SPITYPE_PREFIX) << 12) /* Erase 64 KiB */
+		| (SPITYPE_PREFIX << 14);                    /* Write status */
+}
+
+static void spi_init_cb(void *unused)
+{
+	struct spi_flash flash;
+
+	spi_init();
+	if (spi_flash_probe(0, 0, &flash)) {
+		printk(BIOS_DEBUG, "SPI flash failed initialization!\n");
+		return;
+	}
+	printk(BIOS_DEBUG, "SPI flash successfully initialized\n");
+}
+
+BOOT_STATE_INIT_ENTRY(BS_DEV_INIT, BS_ON_ENTRY, spi_init_cb, NULL);
+
+const struct spi_ctrlr spi_driver = {
+	.xfer = xfer,
+	.max_xfer_size = 64,
+	.deduct_cmd_len = false,
+};
+
+const struct spi_ctrlr_buses spi_ctrlr_bus_map[] = {
+	{
+		.ctrlr = &spi_driver,
+		.bus_start = 0,
+		.bus_end = 0,
+	},
+};
+
+const size_t spi_ctrlr_bus_map_count = ARRAY_SIZE(spi_ctrlr_bus_map);