// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
*
* Derived from linux/drivers/spi/spi-bcm63xx-hsspi.c:
* Copyright (C) 2000-2010 Broadcom Corporation
* Copyright (C) 2012-2013 Jonas Gorski <jogo@openwrt.org>
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <spi.h>
#include <reset.h>
#include <wait_bit.h>
#include <asm/io.h>
#define HSSPI_PP 0
#define SPI_MAX_SYNC_CLOCK 30000000
/* SPI Control register */
#define SPI_CTL_REG 0x000
#define SPI_CTL_CS_POL_SHIFT 0
#define SPI_CTL_CS_POL_MASK (0xff << SPI_CTL_CS_POL_SHIFT)
#define SPI_CTL_CLK_GATE_SHIFT 16
#define SPI_CTL_CLK_GATE_MASK (1 << SPI_CTL_CLK_GATE_SHIFT)
#define SPI_CTL_CLK_POL_SHIFT 17
#define SPI_CTL_CLK_POL_MASK (1 << SPI_CTL_CLK_POL_SHIFT)
/* SPI Interrupts registers */
#define SPI_IR_STAT_REG 0x008
#define SPI_IR_ST_MASK_REG 0x00c
#define SPI_IR_MASK_REG 0x010
#define SPI_IR_CLEAR_ALL 0xff001f1f
/* SPI Ping-Pong Command registers */
#define SPI_CMD_REG (0x080 + (0x40 * (HSSPI_PP)) + 0x00)
#define SPI_CMD_OP_SHIFT 0
#define SPI_CMD_OP_START (0x1 << SPI_CMD_OP_SHIFT)
#define SPI_CMD_PFL_SHIFT 8
#define SPI_CMD_PFL_MASK (0x7 << SPI_CMD_PFL_SHIFT)
#define SPI_CMD_SLAVE_SHIFT 12
#define SPI_CMD_SLAVE_MASK (0x7 << SPI_CMD_SLAVE_SHIFT)
/* SPI Ping-Pong Status registers */
#define SPI_STAT_REG (0x080 + (0x40 * (HSSPI_PP)) + 0x04)
#define SPI_STAT_SRCBUSY_SHIFT 1
#define SPI_STAT_SRCBUSY_MASK (1 << SPI_STAT_SRCBUSY_SHIFT)
/* SPI Profile Clock registers */
#define SPI_PFL_CLK_REG(x) (0x100 + (0x20 * (x)) + 0x00)
#define SPI_PFL_CLK_FREQ_SHIFT 0
#define SPI_PFL_CLK_FREQ_MASK (0x3fff << SPI_PFL_CLK_FREQ_SHIFT)
#define SPI_PFL_CLK_RSTLOOP_SHIFT 15
#define SPI_PFL_CLK_RSTLOOP_MASK (1 << SPI_PFL_CLK_RSTLOOP_SHIFT)
/* SPI Profile Signal registers */
#define SPI_PFL_SIG_REG(x) (0x100 + (0x20 * (x)) + 0x04)
#define SPI_PFL_SIG_LATCHRIS_SHIFT 12
#define SPI_PFL_SIG_LATCHRIS_MASK (1 << SPI_PFL_SIG_LATCHRIS_SHIFT)
#define SPI_PFL_SIG_LAUNCHRIS_SHIFT 13
#define SPI_PFL_SIG_LAUNCHRIS_MASK (1 << SPI_PFL_SIG_LAUNCHRIS_SHIFT)
#define SPI_PFL_SIG_ASYNCIN_SHIFT 16
#define SPI_PFL_SIG_ASYNCIN_MASK (1 << SPI_PFL_SIG_ASYNCIN_SHIFT)
/* SPI Profile Mode registers */
#define SPI_PFL_MODE_REG(x) (0x100 + (0x20 * (x)) + 0x08)
#define SPI_PFL_MODE_FILL_SHIFT 0
#define SPI_PFL_MODE_FILL_MASK (0xff << SPI_PFL_MODE_FILL_SHIFT)
#define SPI_PFL_MODE_MDRDSZ_SHIFT 16
#define SPI_PFL_MODE_MDRDSZ_MASK (1 << SPI_PFL_MODE_MDRDSZ_SHIFT)
#define SPI_PFL_MODE_MDWRSZ_SHIFT 18
#define SPI_PFL_MODE_MDWRSZ_MASK (1 << SPI_PFL_MODE_MDWRSZ_SHIFT)
#define SPI_PFL_MODE_3WIRE_SHIFT 20
#define SPI_PFL_MODE_3WIRE_MASK (1 << SPI_PFL_MODE_3WIRE_SHIFT)
/* SPI Ping-Pong FIFO registers */
#define HSSPI_FIFO_SIZE 0x200
#define HSSPI_FIFO_BASE (0x200 + \
(HSSPI_FIFO_SIZE * HSSPI_PP))
/* SPI Ping-Pong FIFO OP register */
#define HSSPI_FIFO_OP_SIZE 0x2
#define HSSPI_FIFO_OP_REG (HSSPI_FIFO_BASE + 0x00)
#define HSSPI_FIFO_OP_BYTES_SHIFT 0
#define HSSPI_FIFO_OP_BYTES_MASK (0x3ff << HSSPI_FIFO_OP_BYTES_SHIFT)
#define HSSPI_FIFO_OP_MBIT_SHIFT 11
#define HSSPI_FIFO_OP_MBIT_MASK (1 << HSSPI_FIFO_OP_MBIT_SHIFT)
#define HSSPI_FIFO_OP_CODE_SHIFT 13
#define HSSPI_FIFO_OP_READ_WRITE (1 << HSSPI_FIFO_OP_CODE_SHIFT)
#define HSSPI_FIFO_OP_CODE_W (2 << HSSPI_FIFO_OP_CODE_SHIFT)
#define HSSPI_FIFO_OP_CODE_R (3 << HSSPI_FIFO_OP_CODE_SHIFT)
struct bcm63xx_hsspi_priv {
void __iomem *regs;
ulong clk_rate;
uint8_t num_cs;
uint8_t cs_pols;
uint speed;
};
static int bcm63xx_hsspi_cs_info(struct udevice *bus, uint cs,
struct spi_cs_info *info)
{
struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus);
if (cs >= priv->num_cs) {
printf("no cs %u\n", cs);
return -ENODEV;
}
return 0;
}
static int bcm63xx_hsspi_set_mode(struct udevice *bus, uint mode)
{
struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus);
/* clock polarity */
if (mode & SPI_CPOL)
setbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_POL_MASK);
else
clrbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_POL_MASK);
return 0;
}
static int bcm63xx_hsspi_set_speed(struct udevice *bus, uint speed)
{
struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus);
priv->speed = speed;
return 0;
}
static void bcm63xx_hsspi_activate_cs(struct bcm63xx_hsspi_priv *priv,
struct dm_spi_slave_platdata *plat)
{
uint32_t clr, set;
/* profile clock */
set = DIV_ROUND_UP(priv->clk_rate, priv->speed);
set = DIV_ROUND_UP(2048, set);
set &= SPI_PFL_CLK_FREQ_MASK;
set |= SPI_PFL_CLK_RSTLOOP_MASK;
writel_be(set, priv->regs + SPI_PFL_CLK_REG(plat->cs));
/* profile signal */
set = 0;
clr = SPI_PFL_SIG_LAUNCHRIS_MASK |
SPI_PFL_SIG_LATCHRIS_MASK |
SPI_PFL_SIG_ASYNCIN_MASK;
/* latch/launch config */
if (plat->mode & SPI_CPHA)
set |= SPI_PFL_SIG_LAUNCHRIS_MASK;
else
set |= SPI_PFL_SIG_LATCHRIS_MASK;
/* async clk */
if (priv->speed > SPI_MAX_SYNC_CLOCK)
set |= SPI_PFL_SIG_ASYNCIN_MASK;
clrsetbits_be32(priv->regs + SPI_PFL_SIG_REG(plat->cs), clr, set);
/* global control */
set = 0;
clr = 0;
/* invert cs polarity */
if (priv->cs_pols & BIT(plat->cs))
clr |= BIT(plat->cs);
else
set |= BIT(plat->cs);
/* invert dummy cs polarity */
if (priv->cs_pols & BIT(!plat->cs))
clr |= BIT(!plat->cs);
else
set |= BIT(!plat->cs);
clrsetbits_be32(priv->regs + SPI_CTL_REG, clr, set);
}
static void bcm63xx_hsspi_deactivate_cs(struct bcm63xx_hsspi_priv *priv)
{
/* restore cs polarities */
clrsetbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CS_POL_MASK,
priv->cs_pols);
}
/*
* BCM63xx HSSPI driver doesn't allow keeping CS active between transfers
* because they are controlled by HW.
* However, it provides a mechanism to prepend write transfers prior to read
* transfers (with a maximum prepend of 15 bytes), which is usually enough for
* SPI-connected flashes since reading requires prepending a write transfer of
* 5 bytes. On the other hand it also provides a way to invert each CS
* polarity, not only between transfers like the older BCM63xx SPI driver, but
* also the rest of the time.
*
* Instead of using the prepend mechanism, this implementation inverts the
* polarity of both the desired CS and another dummy CS when the bus is
* claimed. This way, the dummy CS is restored to its inactive value when
* transfers are issued and the desired CS is preserved in its active value
* all the time. This hack is also used in the upstream linux driver and
* allows keeping CS active between trasnfers even if the HW doesn't give
* this possibility.
*/
static int bcm63xx_hsspi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev->parent);
struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
size_t data_bytes = bitlen / 8;
size_t step_size = HSSPI_FIFO_SIZE;
uint16_t opcode = 0;
uint32_t val;
const uint8_t *tx = dout;
uint8_t *rx = din;
if (flags & SPI_XFER_BEGIN)
bcm63xx_hsspi_activate_cs(priv, plat);
/* fifo operation */
if (tx && rx)
opcode = HSSPI_FIFO_OP_READ_WRITE;
else if (rx)
opcode = HSSPI_FIFO_OP_CODE_R;
else if (tx)
opcode = HSSPI_FIFO_OP_CODE_W;
if (opcode != HSSPI_FIFO_OP_CODE_R)
step_size -= HSSPI_FIFO_OP_SIZE;
/* dual mode */
if ((opcode == HSSPI_FIFO_OP_CODE_R && plat->mode == SPI_RX_DUAL) ||
(opcode == HSSPI_FIFO_OP_CODE_W && plat->mode == SPI_TX_DUAL))
opcode |= HSSPI_FIFO_OP_MBIT_MASK;
/* profile mode */
val = SPI_PFL_MODE_FILL_MASK |
SPI_PFL_MODE_MDRDSZ_MASK |
SPI_PFL_MODE_MDWRSZ_MASK;
if (plat->mode & SPI_3WIRE)
val |= SPI_PFL_MODE_3WIRE_MASK;
writel_be(val, priv->regs + SPI_PFL_MODE_REG(plat->cs));
/* transfer loop */
while (data_bytes > 0) {
size_t curr_step = min(step_size, data_bytes);
int ret;
/* copy tx data */
if (tx) {
memcpy_toio(priv->regs + HSSPI_FIFO_BASE +
HSSPI_FIFO_OP_SIZE, tx, curr_step);
tx += curr_step;
}
/* set fifo operation */
writew_be(opcode | (curr_step & HSSPI_FIFO_OP_BYTES_MASK),
priv->regs + HSSPI_FIFO_OP_REG);
/* issue the transfer */
val = SPI_CMD_OP_START;
val |= (plat->cs << SPI_CMD_PFL_SHIFT) &
SPI_CMD_PFL_MASK;
val |= (!plat->cs << SPI_CMD_SLAVE_SHIFT) &
SPI_CMD_SLAVE_MASK;
writel_be(val, priv->regs + SPI_CMD_REG);
/* wait for completion */
ret = wait_for_bit_be32(priv->regs + SPI_STAT_REG,
SPI_STAT_SRCBUSY_MASK, false,
1000, false);
if (ret) {
printf("interrupt timeout\n");
return ret;
}
/* copy rx data */
if (rx) {
memcpy_fromio(rx, priv->regs + HSSPI_FIFO_BASE,
curr_step);
rx += curr_step;
}
data_bytes -= curr_step;
}
if (flags & SPI_XFER_END)
bcm63xx_hsspi_deactivate_cs(priv);
return 0;
}
static const struct dm_spi_ops bcm63xx_hsspi_ops = {
.cs_info = bcm63xx_hsspi_cs_info,
.set_mode = bcm63xx_hsspi_set_mode,
.set_speed = bcm63xx_hsspi_set_speed,
.xfer = bcm63xx_hsspi_xfer,
};
static const struct udevice_id bcm63xx_hsspi_ids[] = {
{ .compatible = "brcm,bcm6328-hsspi", },
{ /* sentinel */ }
};
static int bcm63xx_hsspi_child_pre_probe(struct udevice *dev)
{
struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev->parent);
struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
/* check cs */
if (plat->cs >= priv->num_cs) {
printf("no cs %u\n", plat->cs);
return -ENODEV;
}
/* cs polarity */
if (plat->mode & SPI_CS_HIGH)
priv->cs_pols |= BIT(plat->cs);
else
priv->cs_pols &= ~BIT(plat->cs);
return 0;
}
static int bcm63xx_hsspi_probe(struct udevice *dev)
{
struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev);
struct reset_ctl rst_ctl;
struct clk clk;
int ret;
priv->regs = dev_remap_addr(dev);
if (!priv->regs)
return -EINVAL;
priv->num_cs = dev_read_u32_default(dev, "num-cs", 8);
/* enable clock */
ret = clk_get_by_name(dev, "hsspi", &clk);
if (ret < 0)
return ret;
ret = clk_enable(&clk);
if (ret < 0)
return ret;
ret = clk_free(&clk);
if (ret < 0)
return ret;
/* get clock rate */
ret = clk_get_by_name(dev, "pll", &clk);
if (ret < 0)
return ret;
priv->clk_rate = clk_get_rate(&clk);
ret = clk_free(&clk);
if (ret < 0)
return ret;
/* perform reset */
ret = reset_get_by_index(dev, 0, &rst_ctl);
if (ret < 0)
return ret;
ret = reset_deassert(&rst_ctl);
if (ret < 0)
return ret;
ret = reset_free(&rst_ctl);
if (ret < 0)
return ret;
/* initialize hardware */
writel_be(0, priv->regs + SPI_IR_MASK_REG);
/* clear pending interrupts */
writel_be(SPI_IR_CLEAR_ALL, priv->regs + SPI_IR_STAT_REG);
/* enable clk gate */
setbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_GATE_MASK);
/* read default cs polarities */
priv->cs_pols = readl_be(priv->regs + SPI_CTL_REG) &
SPI_CTL_CS_POL_MASK;
return 0;
}
U_BOOT_DRIVER(bcm63xx_hsspi) = {
.name = "bcm63xx_hsspi",
.id = UCLASS_SPI,
.of_match = bcm63xx_hsspi_ids,
.ops = &bcm63xx_hsspi_ops,
.priv_auto_alloc_size = sizeof(struct bcm63xx_hsspi_priv),
.child_pre_probe = bcm63xx_hsspi_child_pre_probe,
.probe = bcm63xx_hsspi_probe,
};