u-boot/drivers/spi/bcmstb_spi.c
Thomas Fitzsimmons 894c3ad27f board: arm: Add support for Broadcom BCM7445
Add support for loading U-Boot on the Broadcom 7445 SoC.  This port
assumes Broadcom's BOLT bootloader is acting as the second stage
bootloader, and U-Boot is acting as the third stage bootloader, loaded
as an ELF program by BOLT.

Signed-off-by: Thomas Fitzsimmons <fitzsim@fitzsim.org>
Cc: Stefan Roese <sr@denx.de>
Cc: Tom Rini <trini@konsulko.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
2018-07-10 16:55:57 -04:00

439 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2018 Cisco Systems, Inc.
*
* Author: Thomas Fitzsimmons <fitzsim@fitzsim.org>
*/
#include <asm/io.h>
#include <command.h>
#include <config.h>
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <log.h>
#include <malloc.h>
#include <spi.h>
#include <time.h>
DECLARE_GLOBAL_DATA_PTR;
#define SPBR_MIN 8
#define BITS_PER_WORD 8
#define NUM_TXRAM 32
#define NUM_RXRAM 32
#define NUM_CDRAM 16
/* hif_mspi register structure. */
struct bcmstb_hif_mspi_regs {
u32 spcr0_lsb; /* 0x000 */
u32 spcr0_msb; /* 0x004 */
u32 spcr1_lsb; /* 0x008 */
u32 spcr1_msb; /* 0x00c */
u32 newqp; /* 0x010 */
u32 endqp; /* 0x014 */
u32 spcr2; /* 0x018 */
u32 reserved0; /* 0x01c */
u32 mspi_status; /* 0x020 */
u32 cptqp; /* 0x024 */
u32 spcr3; /* 0x028 */
u32 revision; /* 0x02c */
u32 reserved1[4]; /* 0x030 */
u32 txram[NUM_TXRAM]; /* 0x040 */
u32 rxram[NUM_RXRAM]; /* 0x0c0 */
u32 cdram[NUM_CDRAM]; /* 0x140 */
u32 write_lock; /* 0x180 */
};
/* hif_mspi masks. */
#define HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK 0x00000080
#define HIF_MSPI_SPCR2_SPE_MASK 0x00000040
#define HIF_MSPI_SPCR2_SPIFIE_MASK 0x00000020
#define HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK 0x00000001
/* bspi offsets. */
#define BSPI_MAST_N_BOOT_CTRL 0x008
/* bspi_raf is not used in this driver. */
/* hif_spi_intr2 offsets and masks. */
#define HIF_SPI_INTR2_CPU_CLEAR 0x08
#define HIF_SPI_INTR2_CPU_MASK_SET 0x10
#define HIF_SPI_INTR2_CPU_MASK_CLEAR 0x14
#define HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK 0x00000020
/* SPI transfer timeout in milliseconds. */
#define HIF_MSPI_WAIT 10
enum bcmstb_base_type {
HIF_MSPI,
BSPI,
HIF_SPI_INTR2,
CS_REG,
BASE_LAST,
};
struct bcmstb_spi_platdata {
void *base[4];
};
struct bcmstb_spi_priv {
struct bcmstb_hif_mspi_regs *regs;
void *bspi;
void *hif_spi_intr2;
void *cs_reg;
int default_cs;
int curr_cs;
uint tx_slot;
uint rx_slot;
u8 saved_cmd[NUM_CDRAM];
uint saved_cmd_len;
void *saved_din_addr;
};
static int bcmstb_spi_ofdata_to_platdata(struct udevice *bus)
{
struct bcmstb_spi_platdata *plat = dev_get_platdata(bus);
const void *fdt = gd->fdt_blob;
int node = dev_of_offset(bus);
int ret = 0;
int i = 0;
struct fdt_resource resource = { 0 };
char *names[BASE_LAST] = { "hif_mspi", "bspi", "hif_spi_intr2",
"cs_reg" };
const phys_addr_t defaults[BASE_LAST] = { BCMSTB_HIF_MSPI_BASE,
BCMSTB_BSPI_BASE,
BCMSTB_HIF_SPI_INTR2,
BCMSTB_CS_REG };
for (i = 0; i < BASE_LAST; i++) {
plat->base[i] = (void *)defaults[i];
ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
names[i], &resource);
if (ret) {
printf("%s: Assuming BCMSTB SPI %s address 0x0x%p\n",
__func__, names[i], (void *)defaults[i]);
} else {
plat->base[i] = (void *)resource.start;
debug("BCMSTB SPI %s address: 0x0x%p\n",
names[i], (void *)plat->base[i]);
}
}
return 0;
}
static void bcmstb_spi_hw_set_parms(struct bcmstb_spi_priv *priv)
{
writel(SPBR_MIN, &priv->regs->spcr0_lsb);
writel(BITS_PER_WORD << 2 | SPI_MODE_3, &priv->regs->spcr0_msb);
}
static void bcmstb_spi_enable_interrupt(void *base, u32 mask)
{
void *reg = base + HIF_SPI_INTR2_CPU_MASK_CLEAR;
writel(readl(reg) | mask, reg);
readl(reg);
}
static void bcmstb_spi_disable_interrupt(void *base, u32 mask)
{
void *reg = base + HIF_SPI_INTR2_CPU_MASK_SET;
writel(readl(reg) | mask, reg);
readl(reg);
}
static void bcmstb_spi_clear_interrupt(void *base, u32 mask)
{
void *reg = base + HIF_SPI_INTR2_CPU_CLEAR;
writel(readl(reg) | mask, reg);
readl(reg);
}
static int bcmstb_spi_probe(struct udevice *bus)
{
struct bcmstb_spi_platdata *plat = dev_get_platdata(bus);
struct bcmstb_spi_priv *priv = dev_get_priv(bus);
priv->regs = plat->base[HIF_MSPI];
priv->bspi = plat->base[BSPI];
priv->hif_spi_intr2 = plat->base[HIF_SPI_INTR2];
priv->cs_reg = plat->base[CS_REG];
priv->default_cs = 0;
priv->curr_cs = -1;
priv->tx_slot = 0;
priv->rx_slot = 0;
memset(priv->saved_cmd, 0, NUM_CDRAM);
priv->saved_cmd_len = 0;
priv->saved_din_addr = NULL;
debug("spi_xfer: tx regs: 0x%p\n", &priv->regs->txram[0]);
debug("spi_xfer: rx regs: 0x%p\n", &priv->regs->rxram[0]);
/* Disable BSPI. */
writel(1, priv->bspi + BSPI_MAST_N_BOOT_CTRL);
readl(priv->bspi + BSPI_MAST_N_BOOT_CTRL);
/* Set up interrupts. */
bcmstb_spi_disable_interrupt(priv->hif_spi_intr2, 0xffffffff);
bcmstb_spi_clear_interrupt(priv->hif_spi_intr2, 0xffffffff);
bcmstb_spi_enable_interrupt(priv->hif_spi_intr2,
HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK);
/* Set up control registers. */
writel(0, &priv->regs->spcr1_lsb);
writel(0, &priv->regs->spcr1_msb);
writel(0, &priv->regs->newqp);
writel(0, &priv->regs->endqp);
writel(HIF_MSPI_SPCR2_SPIFIE_MASK, &priv->regs->spcr2);
writel(0, &priv->regs->spcr3);
bcmstb_spi_hw_set_parms(priv);
return 0;
}
static void bcmstb_spi_submit(struct bcmstb_spi_priv *priv, bool done)
{
debug("WR NEWQP: %d\n", 0);
writel(0, &priv->regs->newqp);
debug("WR ENDQP: %d\n", priv->tx_slot - 1);
writel(priv->tx_slot - 1, &priv->regs->endqp);
if (done) {
debug("WR CDRAM[%d]: %02x\n", priv->tx_slot - 1,
readl(&priv->regs->cdram[priv->tx_slot - 1]) & ~0x80);
writel(readl(&priv->regs->cdram[priv->tx_slot - 1]) & ~0x80,
&priv->regs->cdram[priv->tx_slot - 1]);
}
/* Force chip select first time. */
if (priv->curr_cs != priv->default_cs) {
debug("spi_xfer: switching chip select to %d\n",
priv->default_cs);
writel((readl(priv->cs_reg) & ~0xff) | (1 << priv->default_cs),
priv->cs_reg);
readl(priv->cs_reg);
udelay(10);
priv->curr_cs = priv->default_cs;
}
debug("WR WRITE_LOCK: %02x\n", 1);
writel((readl(&priv->regs->write_lock) &
~HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK) | 1,
&priv->regs->write_lock);
readl(&priv->regs->write_lock);
debug("WR SPCR2: %02x\n",
HIF_MSPI_SPCR2_SPIFIE_MASK |
HIF_MSPI_SPCR2_SPE_MASK |
HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK);
writel(HIF_MSPI_SPCR2_SPIFIE_MASK |
HIF_MSPI_SPCR2_SPE_MASK |
HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK,
&priv->regs->spcr2);
}
static int bcmstb_spi_wait(struct bcmstb_spi_priv *priv)
{
u32 start_time = get_timer(0);
u32 status = readl(&priv->regs->mspi_status);
while (!(status & 1)) {
if (get_timer(start_time) > HIF_MSPI_WAIT)
return -ETIMEDOUT;
status = readl(&priv->regs->mspi_status);
}
writel(readl(&priv->regs->mspi_status) & ~1, &priv->regs->mspi_status);
bcmstb_spi_clear_interrupt(priv->hif_spi_intr2,
HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK);
return 0;
}
static int bcmstb_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
uint len = bitlen / 8;
uint tx_len = len;
uint rx_len = len;
const u8 *out_bytes = (u8 *)dout;
u8 *in_bytes = (u8 *)din;
struct udevice *bus = dev_get_parent(dev);
struct bcmstb_spi_priv *priv = dev_get_priv(bus);
struct bcmstb_hif_mspi_regs *regs = priv->regs;
debug("spi_xfer: %d, t: 0x%p, r: 0x%p, f: %lx\n",
len, dout, din, flags);
debug("spi_xfer: chip select: %x\n", readl(priv->cs_reg) & 0xff);
debug("spi_xfer: tx addr: 0x%p\n", &regs->txram[0]);
debug("spi_xfer: rx addr: 0x%p\n", &regs->rxram[0]);
debug("spi_xfer: cd addr: 0x%p\n", &regs->cdram[0]);
if (flags & SPI_XFER_END) {
debug("spi_xfer: clearing saved din address: 0x%p\n",
priv->saved_din_addr);
priv->saved_din_addr = NULL;
priv->saved_cmd_len = 0;
memset(priv->saved_cmd, 0, NUM_CDRAM);
}
if (bitlen == 0)
return 0;
if (bitlen % 8) {
printf("%s: Non-byte-aligned transfer\n", __func__);
return -EOPNOTSUPP;
}
if (flags & ~(SPI_XFER_BEGIN | SPI_XFER_END)) {
printf("%s: Unsupported flags: %lx\n", __func__, flags);
return -EOPNOTSUPP;
}
if (flags & SPI_XFER_BEGIN) {
priv->tx_slot = 0;
priv->rx_slot = 0;
if (out_bytes && len > NUM_CDRAM) {
printf("%s: Unable to save transfer\n", __func__);
return -EOPNOTSUPP;
}
if (out_bytes && !(flags & SPI_XFER_END)) {
/*
* This is the start of a transmit operation
* that will need repeating if the calling
* code polls for the result. Save it for
* subsequent transmission.
*/
debug("spi_xfer: saving command: %x, %d\n",
out_bytes[0], len);
priv->saved_cmd_len = len;
memcpy(priv->saved_cmd, out_bytes, priv->saved_cmd_len);
}
}
if (!(flags & (SPI_XFER_BEGIN | SPI_XFER_END))) {
if (priv->saved_din_addr == din) {
/*
* The caller is polling for status. Repeat
* the last transmission.
*/
int ret = 0;
debug("spi_xfer: Making recursive call\n");
ret = bcmstb_spi_xfer(dev, priv->saved_cmd_len * 8,
priv->saved_cmd, NULL,
SPI_XFER_BEGIN);
if (ret) {
printf("%s: Recursive call failed\n", __func__);
return ret;
}
} else {
debug("spi_xfer: saving din address: 0x%p\n", din);
priv->saved_din_addr = din;
}
}
while (rx_len > 0) {
priv->rx_slot = priv->tx_slot;
while (priv->tx_slot < NUM_CDRAM && tx_len > 0) {
bcmstb_spi_hw_set_parms(priv);
debug("WR TXRAM[%d]: %02x\n", priv->tx_slot,
out_bytes ? out_bytes[len - tx_len] : 0xff);
writel(out_bytes ? out_bytes[len - tx_len] : 0xff,
&regs->txram[priv->tx_slot << 1]);
debug("WR CDRAM[%d]: %02x\n", priv->tx_slot, 0x8e);
writel(0x8e, &regs->cdram[priv->tx_slot]);
priv->tx_slot++;
tx_len--;
if (!in_bytes)
rx_len--;
}
debug("spi_xfer: early return clauses: %d, %d, %d\n",
len <= NUM_CDRAM,
!in_bytes,
(flags & (SPI_XFER_BEGIN |
SPI_XFER_END)) == SPI_XFER_BEGIN);
if (len <= NUM_CDRAM &&
!in_bytes &&
(flags & (SPI_XFER_BEGIN | SPI_XFER_END)) == SPI_XFER_BEGIN)
return 0;
bcmstb_spi_submit(priv, tx_len == 0);
if (bcmstb_spi_wait(priv) == -ETIMEDOUT) {
printf("%s: Timed out\n", __func__);
return -ETIMEDOUT;
}
priv->tx_slot %= NUM_CDRAM;
if (in_bytes) {
while (priv->rx_slot < NUM_CDRAM && rx_len > 0) {
in_bytes[len - rx_len] =
readl(&regs->rxram[(priv->rx_slot << 1)
+ 1])
& 0xff;
debug("RD RXRAM[%d]: %02x\n",
priv->rx_slot, in_bytes[len - rx_len]);
priv->rx_slot++;
rx_len--;
}
}
}
if (flags & SPI_XFER_END) {
debug("WR WRITE_LOCK: %02x\n", 0);
writel((readl(&priv->regs->write_lock) &
~HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK) | 0,
&priv->regs->write_lock);
readl(&priv->regs->write_lock);
}
return 0;
}
static int bcmstb_spi_set_speed(struct udevice *dev, uint speed)
{
return 0;
}
static int bcmstb_spi_set_mode(struct udevice *dev, uint mode)
{
return 0;
}
static const struct dm_spi_ops bcmstb_spi_ops = {
.xfer = bcmstb_spi_xfer,
.set_speed = bcmstb_spi_set_speed,
.set_mode = bcmstb_spi_set_mode,
};
static const struct udevice_id bcmstb_spi_id[] = {
{ .compatible = "brcm,spi-brcmstb" },
{ }
};
U_BOOT_DRIVER(bcmstb_spi) = {
.name = "bcmstb_spi",
.id = UCLASS_SPI,
.of_match = bcmstb_spi_id,
.ops = &bcmstb_spi_ops,
.ofdata_to_platdata = bcmstb_spi_ofdata_to_platdata,
.probe = bcmstb_spi_probe,
.platdata_auto_alloc_size = sizeof(struct bcmstb_spi_platdata),
.priv_auto_alloc_size = sizeof(struct bcmstb_spi_priv),
};