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Diffstat (limited to 'src/southbridge/intel/ibexpeak/spi.c')
-rw-r--r--src/southbridge/intel/ibexpeak/spi.c744
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;
+}