u-boot/drivers/spi/ich.c
Bin Meng ab20107468 spi: ich: Lock down controller settings if required
Some Intel FSP (like Braswell) does SPI lock-down during the call
to fsp_notify(INIT_PHASE_BOOT). But before SPI lock-down is done,
it's bootloader's responsibility to configure the SPI controller's
opcode registers properly otherwise SPI controller driver doesn't
know how to communicate with the SPI flash device.

Rather than passively doing the opcode configuration, let's add a
simple DTS property "intel,spi-lock-down" and let the driver call
the opcode configuration function if required by such FSP.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2017-10-27 15:13:47 +08:00

718 lines
19 KiB
C

/*
* Copyright (c) 2011-12 The Chromium OS Authors.
*
* SPDX-License-Identifier: GPL-2.0+
*
* This file is derived from the flashrom project.
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <malloc.h>
#include <pch.h>
#include <pci.h>
#include <pci_ids.h>
#include <spi.h>
#include <asm/io.h>
#include "ich.h"
DECLARE_GLOBAL_DATA_PTR;
#ifdef DEBUG_TRACE
#define debug_trace(fmt, args...) debug(fmt, ##args)
#else
#define debug_trace(x, args...)
#endif
static u8 ich_readb(struct ich_spi_priv *priv, int reg)
{
u8 value = readb(priv->base + reg);
debug_trace("read %2.2x from %4.4x\n", value, reg);
return value;
}
static u16 ich_readw(struct ich_spi_priv *priv, int reg)
{
u16 value = readw(priv->base + reg);
debug_trace("read %4.4x from %4.4x\n", value, reg);
return value;
}
static u32 ich_readl(struct ich_spi_priv *priv, int reg)
{
u32 value = readl(priv->base + reg);
debug_trace("read %8.8x from %4.4x\n", value, reg);
return value;
}
static void ich_writeb(struct ich_spi_priv *priv, u8 value, int reg)
{
writeb(value, priv->base + reg);
debug_trace("wrote %2.2x to %4.4x\n", value, reg);
}
static void ich_writew(struct ich_spi_priv *priv, u16 value, int reg)
{
writew(value, priv->base + reg);
debug_trace("wrote %4.4x to %4.4x\n", value, reg);
}
static void ich_writel(struct ich_spi_priv *priv, u32 value, int reg)
{
writel(value, priv->base + reg);
debug_trace("wrote %8.8x to %4.4x\n", value, reg);
}
static void write_reg(struct ich_spi_priv *priv, const void *value,
int dest_reg, uint32_t size)
{
memcpy_toio(priv->base + dest_reg, value, size);
}
static void read_reg(struct ich_spi_priv *priv, int src_reg, void *value,
uint32_t size)
{
memcpy_fromio(value, priv->base + src_reg, size);
}
static void ich_set_bbar(struct ich_spi_priv *ctlr, uint32_t minaddr)
{
const uint32_t bbar_mask = 0x00ffff00;
uint32_t ichspi_bbar;
minaddr &= bbar_mask;
ichspi_bbar = ich_readl(ctlr, ctlr->bbar) & ~bbar_mask;
ichspi_bbar |= minaddr;
ich_writel(ctlr, ichspi_bbar, ctlr->bbar);
}
/* @return 1 if the SPI flash supports the 33MHz speed */
static int ich9_can_do_33mhz(struct udevice *dev)
{
u32 fdod, speed;
/* Observe SPI Descriptor Component Section 0 */
dm_pci_write_config32(dev->parent, 0xb0, 0x1000);
/* Extract the Write/Erase SPI Frequency from descriptor */
dm_pci_read_config32(dev->parent, 0xb4, &fdod);
/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
speed = (fdod >> 21) & 7;
return speed == 1;
}
static int ich_init_controller(struct udevice *dev,
struct ich_spi_platdata *plat,
struct ich_spi_priv *ctlr)
{
ulong sbase_addr;
void *sbase;
/* SBASE is similar */
pch_get_spi_base(dev->parent, &sbase_addr);
sbase = (void *)sbase_addr;
debug("%s: sbase=%p\n", __func__, sbase);
if (plat->ich_version == ICHV_7) {
struct ich7_spi_regs *ich7_spi = sbase;
ctlr->opmenu = offsetof(struct ich7_spi_regs, opmenu);
ctlr->menubytes = sizeof(ich7_spi->opmenu);
ctlr->optype = offsetof(struct ich7_spi_regs, optype);
ctlr->addr = offsetof(struct ich7_spi_regs, spia);
ctlr->data = offsetof(struct ich7_spi_regs, spid);
ctlr->databytes = sizeof(ich7_spi->spid);
ctlr->status = offsetof(struct ich7_spi_regs, spis);
ctlr->control = offsetof(struct ich7_spi_regs, spic);
ctlr->bbar = offsetof(struct ich7_spi_regs, bbar);
ctlr->preop = offsetof(struct ich7_spi_regs, preop);
ctlr->base = ich7_spi;
} else if (plat->ich_version == ICHV_9) {
struct ich9_spi_regs *ich9_spi = sbase;
ctlr->opmenu = offsetof(struct ich9_spi_regs, opmenu);
ctlr->menubytes = sizeof(ich9_spi->opmenu);
ctlr->optype = offsetof(struct ich9_spi_regs, optype);
ctlr->addr = offsetof(struct ich9_spi_regs, faddr);
ctlr->data = offsetof(struct ich9_spi_regs, fdata);
ctlr->databytes = sizeof(ich9_spi->fdata);
ctlr->status = offsetof(struct ich9_spi_regs, ssfs);
ctlr->control = offsetof(struct ich9_spi_regs, ssfc);
ctlr->speed = ctlr->control + 2;
ctlr->bbar = offsetof(struct ich9_spi_regs, bbar);
ctlr->preop = offsetof(struct ich9_spi_regs, preop);
ctlr->bcr = offsetof(struct ich9_spi_regs, bcr);
ctlr->pr = &ich9_spi->pr[0];
ctlr->base = ich9_spi;
} else {
debug("ICH SPI: Unrecognised ICH version %d\n",
plat->ich_version);
return -EINVAL;
}
/* Work out the maximum speed we can support */
ctlr->max_speed = 20000000;
if (plat->ich_version == ICHV_9 && ich9_can_do_33mhz(dev))
ctlr->max_speed = 33000000;
debug("ICH SPI: Version ID %d detected at %p, speed %ld\n",
plat->ich_version, ctlr->base, ctlr->max_speed);
ich_set_bbar(ctlr, 0);
return 0;
}
static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
{
trans->out += bytes;
trans->bytesout -= bytes;
}
static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
{
trans->in += bytes;
trans->bytesin -= bytes;
}
static void spi_lock_down(struct ich_spi_platdata *plat, void *sbase)
{
if (plat->ich_version == ICHV_7) {
struct ich7_spi_regs *ich7_spi = sbase;
setbits_le16(&ich7_spi->spis, SPIS_LOCK);
} else if (plat->ich_version == ICHV_9) {
struct ich9_spi_regs *ich9_spi = sbase;
setbits_le16(&ich9_spi->hsfs, HSFS_FLOCKDN);
}
}
static bool spi_lock_status(struct ich_spi_platdata *plat, void *sbase)
{
int lock = 0;
if (plat->ich_version == ICHV_7) {
struct ich7_spi_regs *ich7_spi = sbase;
lock = readw(&ich7_spi->spis) & SPIS_LOCK;
} else if (plat->ich_version == ICHV_9) {
struct ich9_spi_regs *ich9_spi = sbase;
lock = readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
}
return lock != 0;
}
static void spi_setup_type(struct spi_trans *trans, int data_bytes)
{
trans->type = 0xFF;
/* Try to guess spi type from read/write sizes */
if (trans->bytesin == 0) {
if (trans->bytesout + data_bytes > 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(struct ich_spi_priv *ctlr, struct spi_trans *trans,
bool lock)
{
uint16_t optypes;
uint8_t opmenu[ctlr->menubytes];
trans->opcode = trans->out[0];
spi_use_out(trans, 1);
if (!lock) {
/* The lock is off, so just use index 0. */
ich_writeb(ctlr, trans->opcode, ctlr->opmenu);
optypes = ich_readw(ctlr, ctlr->optype);
optypes = (optypes & 0xfffc) | (trans->type & 0x3);
ich_writew(ctlr, optypes, ctlr->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(ctlr, ctlr->opmenu, opmenu, sizeof(opmenu));
for (opcode_index = 0; opcode_index < ctlr->menubytes;
opcode_index++) {
if (opmenu[opcode_index] == trans->opcode)
break;
}
if (opcode_index == ctlr->menubytes) {
printf("ICH SPI: Opcode %x not found\n",
trans->opcode);
return -EINVAL;
}
optypes = ich_readw(ctlr, ctlr->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) {
printf("ICH SPI: Transaction doesn't fit type %d\n",
optype);
return -ENOSPC;
}
return opcode_index;
}
}
static int spi_setup_offset(struct spi_trans *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:
printf("Unrecognized SPI transaction type %#x\n", trans->type);
return -EPROTO;
}
}
/*
* Wait for up to 6s 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(struct ich_spi_priv *ctlr, u16 bitmask,
int wait_til_set)
{
int timeout = 600000; /* This will result in 6s */
u16 status = 0;
while (timeout--) {
status = ich_readw(ctlr, ctlr->status);
if (wait_til_set ^ ((status & bitmask) == 0)) {
if (wait_til_set) {
ich_writew(ctlr, status & bitmask,
ctlr->status);
}
return status;
}
udelay(10);
}
printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
status, bitmask);
return -ETIMEDOUT;
}
void ich_spi_config_opcode(struct udevice *dev)
{
struct ich_spi_priv *ctlr = dev_get_priv(dev);
/*
* PREOP, OPTYPE, OPMENU1/OPMENU2 registers can be locked down
* to prevent accidental or intentional writes. Before they get
* locked down, these registers should be initialized properly.
*/
ich_writew(ctlr, SPI_OPPREFIX, ctlr->preop);
ich_writew(ctlr, SPI_OPTYPE, ctlr->optype);
ich_writel(ctlr, SPI_OPMENU_LOWER, ctlr->opmenu);
ich_writel(ctlr, SPI_OPMENU_UPPER, ctlr->opmenu + sizeof(u32));
}
static int ich_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
struct udevice *bus = dev_get_parent(dev);
struct ich_spi_platdata *plat = dev_get_platdata(bus);
struct ich_spi_priv *ctlr = dev_get_priv(bus);
uint16_t control;
int16_t opcode_index;
int with_address;
int status;
int bytes = bitlen / 8;
struct spi_trans *trans = &ctlr->trans;
unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
int using_cmd = 0;
bool lock = spi_lock_status(plat, ctlr->base);
int ret;
/* We don't support writing partial bytes */
if (bitlen % 8) {
debug("ICH SPI: Accessing partial bytes not supported\n");
return -EPROTONOSUPPORT;
}
/* An empty end transaction can be ignored */
if (type == SPI_XFER_END && !dout && !din)
return 0;
if (type & SPI_XFER_BEGIN)
memset(trans, '\0', sizeof(*trans));
/* Dp we need to come back later to finish it? */
if (dout && type == SPI_XFER_BEGIN) {
if (bytes > ICH_MAX_CMD_LEN) {
debug("ICH SPI: Command length limit exceeded\n");
return -ENOSPC;
}
memcpy(trans->cmd, dout, bytes);
trans->cmd_len = bytes;
debug_trace("ICH SPI: Saved %d bytes\n", bytes);
return 0;
}
/*
* We process a 'middle' spi_xfer() call, which has no
* SPI_XFER_BEGIN/END, as an independent transaction as if it had
* an end. We therefore repeat the command. This is because ICH
* seems to have no support for this, or because interest (in digging
* out the details and creating a special case in the code) is low.
*/
if (trans->cmd_len) {
trans->out = trans->cmd;
trans->bytesout = trans->cmd_len;
using_cmd = 1;
debug_trace("ICH SPI: Using %d bytes\n", trans->cmd_len);
} else {
trans->out = dout;
trans->bytesout = dout ? bytes : 0;
}
trans->in = din;
trans->bytesin = din ? bytes : 0;
/* There has to always at least be an opcode */
if (!trans->bytesout) {
debug("ICH SPI: No opcode for transfer\n");
return -EPROTO;
}
ret = ich_status_poll(ctlr, SPIS_SCIP, 0);
if (ret < 0)
return ret;
if (plat->ich_version == ICHV_7)
ich_writew(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
else
ich_writeb(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
spi_setup_type(trans, using_cmd ? bytes : 0);
opcode_index = spi_setup_opcode(ctlr, trans, lock);
if (opcode_index < 0)
return -EINVAL;
with_address = spi_setup_offset(trans);
if (with_address < 0)
return -EINVAL;
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 (!lock)
ich_writew(ctlr, trans->opcode, ctlr->preop);
return 0;
}
if (ctlr->speed && ctlr->max_speed >= 33000000) {
int byte;
byte = ich_readb(ctlr, ctlr->speed);
if (ctlr->cur_speed >= 33000000)
byte |= SSFC_SCF_33MHZ;
else
byte &= ~SSFC_SCF_33MHZ;
ich_writeb(ctlr, byte, ctlr->speed);
}
/* See if we have used up the command data */
if (using_cmd && dout && bytes) {
trans->out = dout;
trans->bytesout = bytes;
debug_trace("ICH SPI: Moving to data, %d bytes\n", bytes);
}
/* Preset control fields */
control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
/* Issue atomic preop cycle if needed */
if (ich_readw(ctlr, ctlr->preop))
control |= SPIC_ACS;
if (!trans->bytesout && !trans->bytesin) {
/* SPI addresses are 24 bit only */
if (with_address) {
ich_writel(ctlr, trans->offset & 0x00FFFFFF,
ctlr->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.
*/
ich_writew(ctlr, control, ctlr->control);
/* wait for the result */
status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
if (status < 0)
return status;
if (status & SPIS_FCERR) {
debug("ICH SPI: Command transaction error\n");
return -EIO;
}
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 > ctlr->databytes) {
debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
return -EPROTO;
}
/*
* 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 */
ich_writel(ctlr, trans->offset & 0x00FFFFFF, ctlr->addr);
if (trans->bytesout)
data_length = min(trans->bytesout, ctlr->databytes);
else
data_length = min(trans->bytesin, ctlr->databytes);
/* Program data into FDATA0 to N */
if (trans->bytesout) {
write_reg(ctlr, trans->out, ctlr->data, data_length);
spi_use_out(trans, data_length);
if (with_address)
trans->offset += data_length;
}
/* Add proper control fields' values */
control &= ~((ctlr->databytes - 1) << 8);
control |= SPIC_DS;
control |= (data_length - 1) << 8;
/* write it */
ich_writew(ctlr, control, ctlr->control);
/* Wait for Cycle Done Status or Flash Cycle Error */
status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
if (status < 0)
return status;
if (status & SPIS_FCERR) {
debug("ICH SPI: Data transaction error %x\n", status);
return -EIO;
}
if (trans->bytesin) {
read_reg(ctlr, ctlr->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 */
if (!lock)
ich_writew(ctlr, 0, ctlr->preop);
return 0;
}
static int ich_spi_probe(struct udevice *dev)
{
struct ich_spi_platdata *plat = dev_get_platdata(dev);
struct ich_spi_priv *priv = dev_get_priv(dev);
uint8_t bios_cntl;
int ret;
ret = ich_init_controller(dev, plat, priv);
if (ret)
return ret;
/* Disable the BIOS write protect so write commands are allowed */
ret = pch_set_spi_protect(dev->parent, false);
if (ret == -ENOSYS) {
bios_cntl = ich_readb(priv, priv->bcr);
bios_cntl &= ~BIT(5); /* clear Enable InSMM_STS (EISS) */
bios_cntl |= 1; /* Write Protect Disable (WPD) */
ich_writeb(priv, bios_cntl, priv->bcr);
} else if (ret) {
debug("%s: Failed to disable write-protect: err=%d\n",
__func__, ret);
return ret;
}
/* Lock down SPI controller settings if required */
if (plat->lockdown) {
ich_spi_config_opcode(dev);
spi_lock_down(plat, priv->base);
}
priv->cur_speed = priv->max_speed;
return 0;
}
static int ich_spi_remove(struct udevice *bus)
{
/*
* Configure SPI controller so that the Linux MTD driver can fully
* access the SPI NOR chip
*/
ich_spi_config_opcode(bus);
return 0;
}
static int ich_spi_set_speed(struct udevice *bus, uint speed)
{
struct ich_spi_priv *priv = dev_get_priv(bus);
priv->cur_speed = speed;
return 0;
}
static int ich_spi_set_mode(struct udevice *bus, uint mode)
{
debug("%s: mode=%d\n", __func__, mode);
return 0;
}
static int ich_spi_child_pre_probe(struct udevice *dev)
{
struct udevice *bus = dev_get_parent(dev);
struct ich_spi_platdata *plat = dev_get_platdata(bus);
struct ich_spi_priv *priv = dev_get_priv(bus);
struct spi_slave *slave = dev_get_parent_priv(dev);
/*
* Yes this controller can only write a small number of bytes at
* once! The limit is typically 64 bytes.
*/
slave->max_write_size = priv->databytes;
/*
* ICH 7 SPI controller only supports array read command
* and byte program command for SST flash
*/
if (plat->ich_version == ICHV_7)
slave->mode = SPI_RX_SLOW | SPI_TX_BYTE;
return 0;
}
static int ich_spi_ofdata_to_platdata(struct udevice *dev)
{
struct ich_spi_platdata *plat = dev_get_platdata(dev);
int node = dev_of_offset(dev);
int ret;
ret = fdt_node_check_compatible(gd->fdt_blob, node, "intel,ich7-spi");
if (ret == 0) {
plat->ich_version = ICHV_7;
} else {
ret = fdt_node_check_compatible(gd->fdt_blob, node,
"intel,ich9-spi");
if (ret == 0)
plat->ich_version = ICHV_9;
}
plat->lockdown = fdtdec_get_bool(gd->fdt_blob, node,
"intel,spi-lock-down");
return ret;
}
static const struct dm_spi_ops ich_spi_ops = {
.xfer = ich_spi_xfer,
.set_speed = ich_spi_set_speed,
.set_mode = ich_spi_set_mode,
/*
* cs_info is not needed, since we require all chip selects to be
* in the device tree explicitly
*/
};
static const struct udevice_id ich_spi_ids[] = {
{ .compatible = "intel,ich7-spi" },
{ .compatible = "intel,ich9-spi" },
{ }
};
U_BOOT_DRIVER(ich_spi) = {
.name = "ich_spi",
.id = UCLASS_SPI,
.of_match = ich_spi_ids,
.ops = &ich_spi_ops,
.ofdata_to_platdata = ich_spi_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct ich_spi_platdata),
.priv_auto_alloc_size = sizeof(struct ich_spi_priv),
.child_pre_probe = ich_spi_child_pre_probe,
.probe = ich_spi_probe,
.remove = ich_spi_remove,
.flags = DM_FLAG_OS_PREPARE,
};