Add support for Intel Ibex Peak (Mobile 5) southbridge

Change-Id: If56f2cacc5f1b2ef9c7b6aea508d458a43dd1309
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/3397
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

1 files changed, 744 insertions, 0 deletions

diff --git a/src/southbridge/intel/ibexpeak/spi.c b/src/southbridge/intel/ibexpeak/spi.c
new file mode 100644
index 0000000000..d5cfde50d8
--- /dev/null
+++ b/src/southbridge/intel/ibexpeak/spi.c
@@ -0,0 +1,744 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/* This file is derived from the flashrom project. */
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <delay.h>
+#include <arch/io.h>
+#include <console/console.h>
+#include <device/pci_ids.h>
+
+#include <spi-generic.h>
+
+#define min(a, b) ((a)<(b)?(a):(b))
+
+#ifdef __SMM__
+#include <northbridge/intel/nehalem/pcie_config.c>
+#define pci_read_config_byte(dev, reg, targ)\
+	*(targ) = pcie_read_config8(dev, reg)
+#define pci_read_config_word(dev, reg, targ)\
+	*(targ) = pcie_read_config16(dev, reg)
+#define pci_read_config_dword(dev, reg, targ)\
+	*(targ) = pcie_read_config32(dev, reg)
+#define pci_write_config_byte(dev, reg, val)\
+	pcie_write_config8(dev, reg, val)
+#define pci_write_config_word(dev, reg, val)\
+	pcie_write_config16(dev, reg, val)
+#define pci_write_config_dword(dev, reg, val)\
+	pcie_write_config32(dev, reg, val)
+#else /* !__SMM__ */
+#include <device/device.h>
+#include <device/pci.h>
+#define pci_read_config_byte(dev, reg, targ)\
+	*(targ) = pci_read_config8(dev, reg)
+#define pci_read_config_word(dev, reg, targ)\
+	*(targ) = pci_read_config16(dev, reg)
+#define pci_read_config_dword(dev, reg, targ)\
+	*(targ) = pci_read_config32(dev, reg)
+#define pci_write_config_byte(dev, reg, val)\
+	pci_write_config8(dev, reg, val)
+#define pci_write_config_word(dev, reg, val)\
+	pci_write_config16(dev, reg, val)
+#define pci_write_config_dword(dev, reg, val)\
+	pci_write_config32(dev, reg, val)
+#endif /* !__SMM__ */
+
+typedef struct spi_slave ich_spi_slave;
+
+static int ichspi_lock = 0;
+
+typedef struct ich7_spi_regs {
+	uint16_t spis;
+	uint16_t spic;
+	uint32_t spia;
+	uint64_t spid[8];
+	uint64_t _pad;
+	uint32_t bbar;
+	uint16_t preop;
+	uint16_t optype;
+	uint8_t opmenu[8];
+} __attribute__((packed)) ich7_spi_regs;
+
+typedef struct ich9_spi_regs {
+	uint32_t bfpr;
+	uint16_t hsfs;
+	uint16_t hsfc;
+	uint32_t faddr;
+	uint32_t _reserved0;
+	uint32_t fdata[16];
+	uint32_t frap;
+	uint32_t freg[5];
+	uint32_t _reserved1[3];
+	uint32_t pr[5];
+	uint32_t _reserved2[2];
+	uint8_t ssfs;
+	uint8_t ssfc[3];
+	uint16_t preop;
+	uint16_t optype;
+	uint8_t opmenu[8];
+	uint32_t bbar;
+	uint8_t _reserved3[12];
+	uint32_t fdoc;
+	uint32_t fdod;
+	uint8_t _reserved4[8];
+	uint32_t afc;
+	uint32_t lvscc;
+	uint32_t uvscc;
+	uint8_t _reserved5[4];
+	uint32_t fpb;
+	uint8_t _reserved6[28];
+	uint32_t srdl;
+	uint32_t srdc;
+	uint32_t srd;
+} __attribute__((packed)) ich9_spi_regs;
+
+typedef struct ich_spi_controller {
+	int locked;
+
+	uint8_t *opmenu;
+	int menubytes;
+	uint16_t *preop;
+	uint16_t *optype;
+	uint32_t *addr;
+	uint8_t *data;
+	unsigned databytes;
+	uint8_t *status;
+	uint16_t *control;
+	uint32_t *bbar;
+} ich_spi_controller;
+
+static ich_spi_controller cntlr;
+
+enum {
+	SPIS_SCIP =		0x0001,
+	SPIS_GRANT =		0x0002,
+	SPIS_CDS =		0x0004,
+	SPIS_FCERR =		0x0008,
+	SSFS_AEL =		0x0010,
+	SPIS_LOCK =		0x8000,
+	SPIS_RESERVED_MASK =	0x7ff0,
+	SSFS_RESERVED_MASK =	0x7fe2
+};
+
+enum {
+	SPIC_SCGO =		0x000002,
+	SPIC_ACS =		0x000004,
+	SPIC_SPOP =		0x000008,
+	SPIC_DBC =		0x003f00,
+	SPIC_DS =		0x004000,
+	SPIC_SME =		0x008000,
+	SSFC_SCF_MASK =		0x070000,
+	SSFC_RESERVED =		0xf80000
+};
+
+enum {
+	HSFS_FDONE =		0x0001,
+	HSFS_FCERR =		0x0002,
+	HSFS_AEL =		0x0004,
+	HSFS_BERASE_MASK =	0x0018,
+	HSFS_BERASE_SHIFT =	3,
+	HSFS_SCIP =		0x0020,
+	HSFS_FDOPSS =		0x2000,
+	HSFS_FDV =		0x4000,
+	HSFS_FLOCKDN =		0x8000
+};
+
+enum {
+	HSFC_FGO =		0x0001,
+	HSFC_FCYCLE_MASK =	0x0006,
+	HSFC_FCYCLE_SHIFT =	1,
+	HSFC_FDBC_MASK =	0x3f00,
+	HSFC_FDBC_SHIFT =	8,
+	HSFC_FSMIE =		0x8000
+};
+
+enum {
+	SPI_OPCODE_TYPE_READ_NO_ADDRESS =	0,
+	SPI_OPCODE_TYPE_WRITE_NO_ADDRESS =	1,
+	SPI_OPCODE_TYPE_READ_WITH_ADDRESS =	2,
+	SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS =	3
+};
+
+#if CONFIG_DEBUG_SPI_FLASH
+
+static u8 readb_(const void *addr)
+{
+	u8 v = read8((unsigned long)addr);
+	printk(BIOS_DEBUG, "read %2.2x from %4.4x\n",
+	       v, ((unsigned) addr & 0xffff) - 0xf020);
+	return v;
+}
+
+static u16 readw_(const void *addr)
+{
+	u16 v = read16((unsigned long)addr);
+	printk(BIOS_DEBUG, "read %4.4x from %4.4x\n",
+	       v, ((unsigned) addr & 0xffff) - 0xf020);
+	return v;
+}
+
+static u32 readl_(const void *addr)
+{
+	u32 v = read32((unsigned long)addr);
+	printk(BIOS_DEBUG, "read %8.8x from %4.4x\n",
+	       v, ((unsigned) addr & 0xffff) - 0xf020);
+	return v;
+}
+
+static void writeb_(u8 b, const void *addr)
+{
+	write8((unsigned long)addr, b);
+	printk(BIOS_DEBUG, "wrote %2.2x to %4.4x\n",
+	       b, ((unsigned) addr & 0xffff) - 0xf020);
+}
+
+static void writew_(u16 b, const void *addr)
+{
+	write16((unsigned long)addr, b);
+	printk(BIOS_DEBUG, "wrote %4.4x to %4.4x\n",
+	       b, ((unsigned) addr & 0xffff) - 0xf020);
+}
+
+static void writel_(u32 b, const void *addr)
+{
+	write32((unsigned long)addr, b);
+	printk(BIOS_DEBUG, "wrote %8.8x to %4.4x\n",
+	       b, ((unsigned) addr & 0xffff) - 0xf020);
+}
+
+#else /* CONFIG_DEBUG_SPI_FLASH ^^^ enabled  vvv NOT enabled */
+
+#define readb_(a) read8((uint32_t)a)
+#define readw_(a) read16((uint32_t)a)
+#define readl_(a) read32((uint32_t)a)
+#define writeb_(val, addr) write8((uint32_t)addr, val)
+#define writew_(val, addr) write16((uint32_t)addr, val)
+#define writel_(val, addr) write32((uint32_t)addr, val)
+
+#endif  /* CONFIG_DEBUG_SPI_FLASH ^^^ NOT enabled */
+
+static void write_reg(const void *value, void *dest, uint32_t size)
+{
+	const uint8_t *bvalue = value;
+	uint8_t *bdest = dest;
+
+	while (size >= 4) {
+		writel_(*(const uint32_t *)bvalue, bdest);
+		bdest += 4; bvalue += 4; size -= 4;
+	}
+	while (size) {
+		writeb_(*bvalue, bdest);
+		bdest++; bvalue++; size--;
+	}
+}
+
+static void read_reg(const void *src, void *value, uint32_t size)
+{
+	const uint8_t *bsrc = src;
+	uint8_t *bvalue = value;
+
+	while (size >= 4) {
+		*(uint32_t *)bvalue = readl_(bsrc);
+		bsrc += 4; bvalue += 4; size -= 4;
+	}
+	while (size) {
+		*bvalue = readb_(bsrc);
+		bsrc++; bvalue++; size--;
+	}
+}
+
+static void ich_set_bbar(uint32_t minaddr)
+{
+	const uint32_t bbar_mask = 0x00ffff00;
+	uint32_t ichspi_bbar;
+
+	minaddr &= bbar_mask;
+	ichspi_bbar = readl_(cntlr.bbar) & ~bbar_mask;
+	ichspi_bbar |= minaddr;
+	writel_(ichspi_bbar, cntlr.bbar);
+}
+
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+	printk(BIOS_DEBUG, "spi_cs_is_valid used but not implemented\n");
+	return 0;
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+		unsigned int max_hz, unsigned int mode)
+{
+	ich_spi_slave *slave = malloc(sizeof(*slave));
+
+	if (!slave) {
+		printk(BIOS_DEBUG, "ICH SPI: Bad allocation\n");
+		return NULL;
+	}
+
+	memset(slave, 0, sizeof(*slave));
+
+	slave->bus = bus;
+	slave->cs = cs;
+	return slave;
+}
+
+/*
+ * Check if this device ID matches one of supported Intel PCH devices.
+ *
+ * Return the ICH version if there is a match, or zero otherwise.
+ */
+static inline int get_ich_version(uint16_t device_id)
+{
+	if (device_id == PCI_DEVICE_ID_INTEL_TGP_LPC)
+		return 7;
+
+	// FIXME add all Ibex Peak PCI IDs
+	if (device_id >= 0x3b07 &&
+	     device_id <= 0x3b07)
+		return 9;
+
+	return 0;
+}
+
+void spi_init(void)
+{
+	int ich_version = 0;
+
+	uint8_t *rcrb; /* Root Complex Register Block */
+	uint32_t rcba; /* Root Complex Base Address */
+	uint8_t bios_cntl;
+	device_t dev;
+	uint32_t ids;
+	uint16_t vendor_id, device_id;
+
+#ifdef __SMM__
+	dev = PCI_DEV(0, 31, 0);
+#else
+	dev = dev_find_slot(0, PCI_DEVFN(31, 0));
+#endif
+	pci_read_config_dword(dev, 0, &ids);
+	vendor_id = ids;
+	device_id = (ids >> 16);
+
+	if (vendor_id != PCI_VENDOR_ID_INTEL) {
+		printk(BIOS_DEBUG, "ICH SPI: No ICH found.\n");
+		return;
+	}
+
+	ich_version = get_ich_version(device_id);
+
+	if (!ich_version) {
+		printk(BIOS_DEBUG, "ICH SPI: No known ICH found.\n");
+		return;
+	}
+
+	pci_read_config_dword(dev, 0xf0, &rcba);
+	/* Bits 31-14 are the base address, 13-1 are reserved, 0 is enable. */
+	rcrb = (uint8_t *)(rcba & 0xffffc000);
+	switch (ich_version) {
+	case 7:
+		{
+			const uint16_t ich7_spibar_offset = 0x3020;
+			ich7_spi_regs *ich7_spi =
+				(ich7_spi_regs *)(rcrb + ich7_spibar_offset);
+
+			ichspi_lock = readw_(&ich7_spi->spis) & SPIS_LOCK;
+			cntlr.opmenu = ich7_spi->opmenu;
+			cntlr.menubytes = sizeof(ich7_spi->opmenu);
+			cntlr.optype = &ich7_spi->optype;
+			cntlr.addr = &ich7_spi->spia;
+			cntlr.data = (uint8_t *)ich7_spi->spid;
+			cntlr.databytes = sizeof(ich7_spi->spid);
+			cntlr.status = (uint8_t *)&ich7_spi->spis;
+			cntlr.control = &ich7_spi->spic;
+			cntlr.bbar = &ich7_spi->bbar;
+			cntlr.preop = &ich7_spi->preop;
+			break;
+		}
+	case 9:
+		{
+			const uint16_t ich9_spibar_offset = 0x3800;
+			ich9_spi_regs *ich9_spi =
+				(ich9_spi_regs *)(rcrb + ich9_spibar_offset);
+			ichspi_lock = readw_(&ich9_spi->hsfs) & HSFS_FLOCKDN;
+			cntlr.opmenu = ich9_spi->opmenu;
+			cntlr.menubytes = sizeof(ich9_spi->opmenu);
+			cntlr.optype = &ich9_spi->optype;
+			cntlr.addr = &ich9_spi->faddr;
+			cntlr.data = (uint8_t *)ich9_spi->fdata;
+			cntlr.databytes = sizeof(ich9_spi->fdata);
+			cntlr.status = &ich9_spi->ssfs;
+			cntlr.control = (uint16_t *)ich9_spi->ssfc;
+			cntlr.bbar = &ich9_spi->bbar;
+			cntlr.preop = &ich9_spi->preop;
+			break;
+		}
+	default:
+		printk(BIOS_DEBUG, "ICH SPI: Unrecognized ICH version %d.\n", ich_version);
+	}
+
+	ich_set_bbar(0);
+
+	/* Disable the BIOS write protect so write commands are allowed. */
+	pci_read_config_byte(dev, 0xdc, &bios_cntl);
+	switch (ich_version) {
+	case 9:
+		/* Deassert SMM BIOS Write Protect Disable. */
+		bios_cntl &= ~(1 << 5);
+		break;
+
+	default:
+		break;
+	}
+	pci_write_config_byte(dev, 0xdc, bios_cntl | 0x1);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+	/* Handled by ICH automatically. */
+	return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+	/* Handled by ICH automatically. */
+}
+
+void spi_cs_activate(struct spi_slave *slave)
+{
+	/* Handled by ICH automatically. */
+}
+
+void spi_cs_deactivate(struct spi_slave *slave)
+{
+	/* Handled by ICH automatically. */
+}
+
+typedef struct spi_transaction {
+	const uint8_t *out;
+	uint32_t bytesout;
+	uint8_t *in;
+	uint32_t bytesin;
+	uint8_t type;
+	uint8_t opcode;
+	uint32_t offset;
+} spi_transaction;
+
+static inline void spi_use_out(spi_transaction *trans, unsigned bytes)
+{
+	trans->out += bytes;
+	trans->bytesout -= bytes;
+}
+
+static inline void spi_use_in(spi_transaction *trans, unsigned bytes)
+{
+	trans->in += bytes;
+	trans->bytesin -= bytes;
+}
+
+static void spi_setup_type(spi_transaction *trans)
+{
+	trans->type = 0xFF;
+
+	/* Try to guess spi type from read/write sizes. */
+	if (trans->bytesin == 0) {
+		if (trans->bytesout > 4)
+			/*
+			 * If bytesin = 0 and bytesout > 4, we presume this is
+			 * a write data operation, which is accompanied by an
+			 * address.
+			 */
+			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
+		else
+			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
+		return;
+	}
+
+	if (trans->bytesout == 1) { /* and bytesin is > 0 */
+		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
+		return;
+	}
+
+	if (trans->bytesout == 4) { /* and bytesin is > 0 */
+		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
+	}
+
+	/* Fast read command is called with 5 bytes instead of 4 */
+	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
+		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
+		--trans->bytesout;
+	}
+}
+
+static int spi_setup_opcode(spi_transaction *trans)
+{
+	uint16_t optypes;
+	uint8_t opmenu[cntlr.menubytes];
+
+	trans->opcode = trans->out[0];
+	spi_use_out(trans, 1);
+	if (!ichspi_lock) {
+		/* The lock is off, so just use index 0. */
+		writeb_(trans->opcode, cntlr.opmenu);
+		optypes = readw_(cntlr.optype);
+		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
+		writew_(optypes, cntlr.optype);
+		return 0;
+	} else {
+		/* The lock is on. See if what we need is on the menu. */
+		uint8_t optype;
+		uint16_t opcode_index;
+
+		/* Write Enable is handled as atomic prefix */
+		if (trans->opcode == SPI_OPCODE_WREN)
+			return 0;
+
+		read_reg(cntlr.opmenu, opmenu, sizeof(opmenu));
+		for (opcode_index = 0; opcode_index < cntlr.menubytes;
+				opcode_index++) {
+			if (opmenu[opcode_index] == trans->opcode)
+				break;
+		}
+
+		if (opcode_index == cntlr.menubytes) {
+			printk(BIOS_DEBUG, "ICH SPI: Opcode %x not found\n",
+				trans->opcode);
+			return -1;
+		}
+
+		optypes = readw_(cntlr.optype);
+		optype = (optypes >> (opcode_index * 2)) & 0x3;
+		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
+			optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
+			trans->bytesout >= 3) {
+			/* We guessed wrong earlier. Fix it up. */
+			trans->type = optype;
+		}
+		if (optype != trans->type) {
+			printk(BIOS_DEBUG, "ICH SPI: Transaction doesn't fit type %d\n",
+				optype);
+			return -1;
+		}
+		return opcode_index;
+	}
+}
+
+static int spi_setup_offset(spi_transaction *trans)
+{
+	/* Separate the SPI address and data. */
+	switch (trans->type) {
+	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
+	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
+		return 0;
+	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
+	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
+		trans->offset = ((uint32_t)trans->out[0] << 16) |
+				((uint32_t)trans->out[1] << 8) |
+				((uint32_t)trans->out[2] << 0);
+		spi_use_out(trans, 3);
+		return 1;
+	default:
+		printk(BIOS_DEBUG, "Unrecognized SPI transaction type %#x\n", trans->type);
+		return -1;
+	}
+}
+
+/*
+ * Wait for up to 60ms til status register bit(s) turn 1 (in case wait_til_set
+ * below is True) or 0. In case the wait was for the bit(s) to set - write
+ * those bits back, which would cause resetting them.
+ *
+ * Return the last read status value on success or -1 on failure.
+ */
+static int ich_status_poll(u16 bitmask, int wait_til_set)
+{
+	int timeout = 6000; /* This will result in 60 ms */
+	u16 status = 0;
+
+	while (timeout--) {
+		status = readw_(cntlr.status);
+		if (wait_til_set ^ ((status & bitmask) == 0)) {
+			if (wait_til_set)
+				writew_((status & bitmask), cntlr.status);
+			return status;
+		}
+		udelay(10);
+	}
+
+	printk(BIOS_DEBUG, "ICH SPI: SCIP timeout, read %x, expected %x\n",
+		status, bitmask);
+	return -1;
+}
+
+int spi_xfer(struct spi_slave *slave, const void *dout,
+		unsigned int bitsout, void *din, unsigned int bitsin)
+{
+	uint16_t control;
+	int16_t opcode_index;
+	int with_address;
+	int status;
+
+	spi_transaction trans = {
+		dout, bitsout / 8,
+		din, bitsin / 8,
+		0xff, 0xff, 0
+	};
+
+	/* There has to always at least be an opcode. */
+	if (!bitsout || !dout) {
+		printk(BIOS_DEBUG, "ICH SPI: No opcode for transfer\n");
+		return -1;
+	}
+	/* Make sure if we read something we have a place to put it. */
+	if (bitsin != 0 && !din) {
+		printk(BIOS_DEBUG, "ICH SPI: Read but no target buffer\n");
+		return -1;
+	}
+	/* Right now we don't support writing partial bytes. */
+	if (bitsout % 8 || bitsin % 8) {
+		printk(BIOS_DEBUG, "ICH SPI: Accessing partial bytes not supported\n");
+		return -1;
+	}
+
+	if (ich_status_poll(SPIS_SCIP, 0) == -1)
+		return -1;
+
+	writew_(SPIS_CDS | SPIS_FCERR, cntlr.status);
+
+	spi_setup_type(&trans);
+	if ((opcode_index = spi_setup_opcode(&trans)) < 0)
+		return -1;
+	if ((with_address = spi_setup_offset(&trans)) < 0)
+		return -1;
+
+	if (trans.opcode == SPI_OPCODE_WREN) {
+		/*
+		 * Treat Write Enable as Atomic Pre-Op if possible
+		 * in order to prevent the Management Engine from
+		 * issuing a transaction between WREN and DATA.
+		 */
+		if (!ichspi_lock)
+			writew_(trans.opcode, cntlr.preop);
+		return 0;
+	}
+
+	/* Preset control fields */
+	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
+
+	/* Issue atomic preop cycle if needed */
+	if (readw_(cntlr.preop))
+		control |= SPIC_ACS;
+
+	if (!trans.bytesout && !trans.bytesin) {
+		/* SPI addresses are 24 bit only */
+		if (with_address)
+			writel_(trans.offset & 0x00FFFFFF, cntlr.addr);
+
+		/*
+		 * This is a 'no data' command (like Write Enable), its
+		 * bitesout size was 1, decremented to zero while executing
+		 * spi_setup_opcode() above. Tell the chip to send the
+		 * command.
+		 */
+		writew_(control, cntlr.control);
+
+		/* wait for the result */
+		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
+		if (status == -1)
+			return -1;
+
+		if (status & SPIS_FCERR) {
+			printk(BIOS_DEBUG, "ICH SPI: Command transaction error\n");
+			return -1;
+		}
+
+		return 0;
+	}
+
+	/*
+	 * Check if this is a write command atempting to transfer more bytes
+	 * than the controller can handle. Iterations for writes are not
+	 * supported here because each SPI write command needs to be preceded
+	 * and followed by other SPI commands, and this sequence is controlled
+	 * by the SPI chip driver.
+	 */
+	if (trans.bytesout > cntlr.databytes) {
+		printk(BIOS_DEBUG, "ICH SPI: Too much to write. Does your SPI chip driver use"
+		     " CONTROLLER_PAGE_LIMIT?\n");
+		return -1;
+	}
+
+	/*
+	 * Read or write up to databytes bytes at a time until everything has
+	 * been sent.
+	 */
+	while (trans.bytesout || trans.bytesin) {
+		uint32_t data_length;
+
+		/* SPI addresses are 24 bit only */
+		writel_(trans.offset & 0x00FFFFFF, cntlr.addr);
+
+		if (trans.bytesout)
+			data_length = min(trans.bytesout, cntlr.databytes);
+		else
+			data_length = min(trans.bytesin, cntlr.databytes);
+
+		/* Program data into FDATA0 to N */
+		if (trans.bytesout) {
+			write_reg(trans.out, cntlr.data, data_length);
+			spi_use_out(&trans, data_length);
+			if (with_address)
+				trans.offset += data_length;
+		}
+
+		/* Add proper control fields' values */
+		control &= ~((cntlr.databytes - 1) << 8);
+		control |= SPIC_DS;
+		control |= (data_length - 1) << 8;
+
+		/* write it */
+		writew_(control, cntlr.control);
+
+		/* Wait for Cycle Done Status or Flash Cycle Error. */
+		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
+		if (status == -1)
+			return -1;
+
+		if (status & SPIS_FCERR) {
+			printk(BIOS_DEBUG, "ICH SPI: Data transaction error\n");
+			return -1;
+		}
+
+		if (trans.bytesin) {
+			read_reg(cntlr.data, trans.in, data_length);
+			spi_use_in(&trans, data_length);
+			if (with_address)
+				trans.offset += data_length;
+		}
+	}
+
+	/* Clear atomic preop now that xfer is done */
+	writew_(0, cntlr.preop);
+
+	return 0;
+}