u-boot/drivers/spi/tegra210_qspi.c

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/*
* NVIDIA Tegra210 QSPI controller driver
*
* (C) Copyright 2015 NVIDIA Corporation <www.nvidia.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch-tegra/clk_rst.h>
#include <spi.h>
#include <fdtdec.h>
#include "tegra_spi.h"
DECLARE_GLOBAL_DATA_PTR;
/* COMMAND1 */
#define QSPI_CMD1_GO BIT(31)
#define QSPI_CMD1_M_S BIT(30)
#define QSPI_CMD1_MODE_MASK GENMASK(1,0)
#define QSPI_CMD1_MODE_SHIFT 28
#define QSPI_CMD1_CS_SEL_MASK GENMASK(1,0)
#define QSPI_CMD1_CS_SEL_SHIFT 26
#define QSPI_CMD1_CS_POL_INACTIVE0 BIT(22)
#define QSPI_CMD1_CS_SW_HW BIT(21)
#define QSPI_CMD1_CS_SW_VAL BIT(20)
#define QSPI_CMD1_IDLE_SDA_MASK GENMASK(1,0)
#define QSPI_CMD1_IDLE_SDA_SHIFT 18
#define QSPI_CMD1_BIDIR BIT(17)
#define QSPI_CMD1_LSBI_FE BIT(16)
#define QSPI_CMD1_LSBY_FE BIT(15)
#define QSPI_CMD1_BOTH_EN_BIT BIT(14)
#define QSPI_CMD1_BOTH_EN_BYTE BIT(13)
#define QSPI_CMD1_RX_EN BIT(12)
#define QSPI_CMD1_TX_EN BIT(11)
#define QSPI_CMD1_PACKED BIT(5)
#define QSPI_CMD1_BITLEN_MASK GENMASK(4,0)
#define QSPI_CMD1_BITLEN_SHIFT 0
/* COMMAND2 */
#define QSPI_CMD2_TX_CLK_TAP_DELAY BIT(6)
#define QSPI_CMD2_TX_CLK_TAP_DELAY_MASK GENMASK(11,6)
#define QSPI_CMD2_RX_CLK_TAP_DELAY BIT(0)
#define QSPI_CMD2_RX_CLK_TAP_DELAY_MASK GENMASK(5,0)
/* TRANSFER STATUS */
#define QSPI_XFER_STS_RDY BIT(30)
/* FIFO STATUS */
#define QSPI_FIFO_STS_CS_INACTIVE BIT(31)
#define QSPI_FIFO_STS_FRAME_END BIT(30)
#define QSPI_FIFO_STS_RX_FIFO_FLUSH BIT(15)
#define QSPI_FIFO_STS_TX_FIFO_FLUSH BIT(14)
#define QSPI_FIFO_STS_ERR BIT(8)
#define QSPI_FIFO_STS_TX_FIFO_OVF BIT(7)
#define QSPI_FIFO_STS_TX_FIFO_UNR BIT(6)
#define QSPI_FIFO_STS_RX_FIFO_OVF BIT(5)
#define QSPI_FIFO_STS_RX_FIFO_UNR BIT(4)
#define QSPI_FIFO_STS_TX_FIFO_FULL BIT(3)
#define QSPI_FIFO_STS_TX_FIFO_EMPTY BIT(2)
#define QSPI_FIFO_STS_RX_FIFO_FULL BIT(1)
#define QSPI_FIFO_STS_RX_FIFO_EMPTY BIT(0)
#define QSPI_TIMEOUT 1000
struct qspi_regs {
u32 command1; /* 000:QSPI_COMMAND1 register */
u32 command2; /* 004:QSPI_COMMAND2 register */
u32 timing1; /* 008:QSPI_CS_TIM1 register */
u32 timing2; /* 00c:QSPI_CS_TIM2 register */
u32 xfer_status;/* 010:QSPI_TRANS_STATUS register */
u32 fifo_status;/* 014:QSPI_FIFO_STATUS register */
u32 tx_data; /* 018:QSPI_TX_DATA register */
u32 rx_data; /* 01c:QSPI_RX_DATA register */
u32 dma_ctl; /* 020:QSPI_DMA_CTL register */
u32 dma_blk; /* 024:QSPI_DMA_BLK register */
u32 rsvd[56]; /* 028-107 reserved */
u32 tx_fifo; /* 108:QSPI_FIFO1 register */
u32 rsvd2[31]; /* 10c-187 reserved */
u32 rx_fifo; /* 188:QSPI_FIFO2 register */
u32 spare_ctl; /* 18c:QSPI_SPARE_CTRL register */
};
struct tegra210_qspi_priv {
struct qspi_regs *regs;
unsigned int freq;
unsigned int mode;
int periph_id;
int valid;
int last_transaction_us;
};
static int tegra210_qspi_ofdata_to_platdata(struct udevice *bus)
{
struct tegra_spi_platdata *plat = bus->platdata;
const void *blob = gd->fdt_blob;
int node = bus->of_offset;
plat->base = dev_get_addr(bus);
plat->periph_id = clock_decode_periph_id(blob, node);
if (plat->periph_id == PERIPH_ID_NONE) {
debug("%s: could not decode periph id %d\n", __func__,
plat->periph_id);
return -FDT_ERR_NOTFOUND;
}
/* Use 500KHz as a suitable default */
plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency",
500000);
plat->deactivate_delay_us = fdtdec_get_int(blob, node,
"spi-deactivate-delay", 0);
debug("%s: base=%#08lx, periph_id=%d, max-frequency=%d, deactivate_delay=%d\n",
__func__, plat->base, plat->periph_id, plat->frequency,
plat->deactivate_delay_us);
return 0;
}
static int tegra210_qspi_probe(struct udevice *bus)
{
struct tegra_spi_platdata *plat = dev_get_platdata(bus);
struct tegra210_qspi_priv *priv = dev_get_priv(bus);
priv->regs = (struct qspi_regs *)plat->base;
priv->last_transaction_us = timer_get_us();
priv->freq = plat->frequency;
priv->periph_id = plat->periph_id;
return 0;
}
static int tegra210_qspi_claim_bus(struct udevice *bus)
{
struct tegra210_qspi_priv *priv = dev_get_priv(bus);
struct qspi_regs *regs = priv->regs;
/* Change SPI clock to correct frequency, PLLP_OUT0 source */
clock_start_periph_pll(priv->periph_id, CLOCK_ID_PERIPH, priv->freq);
debug("%s: FIFO STATUS = %08x\n", __func__, readl(&regs->fifo_status));
/* Set master mode and sw controlled CS */
setbits_le32(&regs->command1, QSPI_CMD1_M_S | QSPI_CMD1_CS_SW_HW |
(priv->mode << QSPI_CMD1_MODE_SHIFT));
debug("%s: COMMAND1 = %08x\n", __func__, readl(&regs->command1));
return 0;
}
/**
* Activate the CS by driving it LOW
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
*/
static void spi_cs_activate(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct tegra_spi_platdata *pdata = dev_get_platdata(bus);
struct tegra210_qspi_priv *priv = dev_get_priv(bus);
/* If it's too soon to do another transaction, wait */
if (pdata->deactivate_delay_us &&
priv->last_transaction_us) {
ulong delay_us; /* The delay completed so far */
delay_us = timer_get_us() - priv->last_transaction_us;
if (delay_us < pdata->deactivate_delay_us)
udelay(pdata->deactivate_delay_us - delay_us);
}
clrbits_le32(&priv->regs->command1, QSPI_CMD1_CS_SW_VAL);
}
/**
* Deactivate the CS by driving it HIGH
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
*/
static void spi_cs_deactivate(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct tegra_spi_platdata *pdata = dev_get_platdata(bus);
struct tegra210_qspi_priv *priv = dev_get_priv(bus);
setbits_le32(&priv->regs->command1, QSPI_CMD1_CS_SW_VAL);
/* Remember time of this transaction so we can honour the bus delay */
if (pdata->deactivate_delay_us)
priv->last_transaction_us = timer_get_us();
debug("Deactivate CS, bus '%s'\n", bus->name);
}
static int tegra210_qspi_xfer(struct udevice *dev, unsigned int bitlen,
const void *data_out, void *data_in,
unsigned long flags)
{
struct udevice *bus = dev->parent;
struct tegra210_qspi_priv *priv = dev_get_priv(bus);
struct qspi_regs *regs = priv->regs;
u32 reg, tmpdout, tmpdin = 0;
const u8 *dout = data_out;
u8 *din = data_in;
int num_bytes, tm, ret;
debug("%s: slave %u:%u dout %p din %p bitlen %u\n",
__func__, bus->seq, spi_chip_select(dev), dout, din, bitlen);
if (bitlen % 8)
return -1;
num_bytes = bitlen / 8;
ret = 0;
/* clear all error status bits */
reg = readl(&regs->fifo_status);
writel(reg, &regs->fifo_status);
/* flush RX/TX FIFOs */
setbits_le32(&regs->fifo_status,
(QSPI_FIFO_STS_RX_FIFO_FLUSH |
QSPI_FIFO_STS_TX_FIFO_FLUSH));
tm = QSPI_TIMEOUT;
while ((tm && readl(&regs->fifo_status) &
(QSPI_FIFO_STS_RX_FIFO_FLUSH |
QSPI_FIFO_STS_TX_FIFO_FLUSH))) {
tm--;
udelay(1);
}
if (!tm) {
printf("%s: timeout during QSPI FIFO flush!\n",
__func__);
return -1;
}
/*
* Notes:
* 1. don't set LSBY_FE, so no need to swap bytes from/to TX/RX FIFOs;
* 2. don't set RX_EN and TX_EN yet.
* (SW needs to make sure that while programming the blk_size,
* tx_en and rx_en bits must be zero)
* [TODO] I (Yen Lin) have problems when both RX/TX EN bits are set
* i.e., both dout and din are not NULL.
*/
clrsetbits_le32(&regs->command1,
(QSPI_CMD1_LSBI_FE | QSPI_CMD1_LSBY_FE |
QSPI_CMD1_RX_EN | QSPI_CMD1_TX_EN),
(spi_chip_select(dev) << QSPI_CMD1_CS_SEL_SHIFT));
/* set xfer size to 1 block (32 bits) */
writel(0, &regs->dma_blk);
if (flags & SPI_XFER_BEGIN)
spi_cs_activate(dev);
/* handle data in 32-bit chunks */
while (num_bytes > 0) {
int bytes;
tmpdout = 0;
bytes = (num_bytes > 4) ? 4 : num_bytes;
if (dout != NULL) {
memcpy((void *)&tmpdout, (void *)dout, bytes);
dout += bytes;
num_bytes -= bytes;
writel(tmpdout, &regs->tx_fifo);
setbits_le32(&regs->command1, QSPI_CMD1_TX_EN);
}
if (din != NULL)
setbits_le32(&regs->command1, QSPI_CMD1_RX_EN);
/* clear ready bit */
setbits_le32(&regs->xfer_status, QSPI_XFER_STS_RDY);
clrsetbits_le32(&regs->command1,
QSPI_CMD1_BITLEN_MASK << QSPI_CMD1_BITLEN_SHIFT,
(bytes * 8 - 1) << QSPI_CMD1_BITLEN_SHIFT);
/* Need to stabilize other reg bits before GO bit set.
* As per the TRM:
* "For successful operation at various freq combinations,
* a minimum of 4-5 spi_clk cycle delay might be required
* before enabling the PIO or DMA bits. The worst case delay
* calculation can be done considering slowest qspi_clk as
* 1MHz. Based on that 1us delay should be enough before
* enabling PIO or DMA." Padded another 1us for safety.
*/
udelay(2);
setbits_le32(&regs->command1, QSPI_CMD1_GO);
udelay(1);
/*
* Wait for SPI transmit FIFO to empty, or to time out.
* The RX FIFO status will be read and cleared last
*/
for (tm = 0; tm < QSPI_TIMEOUT; ++tm) {
u32 fifo_status, xfer_status;
xfer_status = readl(&regs->xfer_status);
if (!(xfer_status & QSPI_XFER_STS_RDY))
continue;
fifo_status = readl(&regs->fifo_status);
if (fifo_status & QSPI_FIFO_STS_ERR) {
debug("%s: got a fifo error: ", __func__);
if (fifo_status & QSPI_FIFO_STS_TX_FIFO_OVF)
debug("tx FIFO overflow ");
if (fifo_status & QSPI_FIFO_STS_TX_FIFO_UNR)
debug("tx FIFO underrun ");
if (fifo_status & QSPI_FIFO_STS_RX_FIFO_OVF)
debug("rx FIFO overflow ");
if (fifo_status & QSPI_FIFO_STS_RX_FIFO_UNR)
debug("rx FIFO underrun ");
if (fifo_status & QSPI_FIFO_STS_TX_FIFO_FULL)
debug("tx FIFO full ");
if (fifo_status & QSPI_FIFO_STS_TX_FIFO_EMPTY)
debug("tx FIFO empty ");
if (fifo_status & QSPI_FIFO_STS_RX_FIFO_FULL)
debug("rx FIFO full ");
if (fifo_status & QSPI_FIFO_STS_RX_FIFO_EMPTY)
debug("rx FIFO empty ");
debug("\n");
break;
}
if (!(fifo_status & QSPI_FIFO_STS_RX_FIFO_EMPTY)) {
tmpdin = readl(&regs->rx_fifo);
if (din != NULL) {
memcpy(din, &tmpdin, bytes);
din += bytes;
num_bytes -= bytes;
}
}
break;
}
if (tm >= QSPI_TIMEOUT)
ret = tm;
/* clear ACK RDY, etc. bits */
writel(readl(&regs->fifo_status), &regs->fifo_status);
}
if (flags & SPI_XFER_END)
spi_cs_deactivate(dev);
debug("%s: transfer ended. Value=%08x, fifo_status = %08x\n",
__func__, tmpdin, readl(&regs->fifo_status));
if (ret) {
printf("%s: timeout during SPI transfer, tm %d\n",
__func__, ret);
return -1;
}
return ret;
}
static int tegra210_qspi_set_speed(struct udevice *bus, uint speed)
{
struct tegra_spi_platdata *plat = bus->platdata;
struct tegra210_qspi_priv *priv = dev_get_priv(bus);
if (speed > plat->frequency)
speed = plat->frequency;
priv->freq = speed;
debug("%s: regs=%p, speed=%d\n", __func__, priv->regs, priv->freq);
return 0;
}
static int tegra210_qspi_set_mode(struct udevice *bus, uint mode)
{
struct tegra210_qspi_priv *priv = dev_get_priv(bus);
priv->mode = mode;
debug("%s: regs=%p, mode=%d\n", __func__, priv->regs, priv->mode);
return 0;
}
static const struct dm_spi_ops tegra210_qspi_ops = {
.claim_bus = tegra210_qspi_claim_bus,
.xfer = tegra210_qspi_xfer,
.set_speed = tegra210_qspi_set_speed,
.set_mode = tegra210_qspi_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 tegra210_qspi_ids[] = {
{ .compatible = "nvidia,tegra210-qspi" },
{ }
};
U_BOOT_DRIVER(tegra210_qspi) = {
.name = "tegra210-qspi",
.id = UCLASS_SPI,
.of_match = tegra210_qspi_ids,
.ops = &tegra210_qspi_ops,
.ofdata_to_platdata = tegra210_qspi_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct tegra_spi_platdata),
.priv_auto_alloc_size = sizeof(struct tegra210_qspi_priv),
.per_child_auto_alloc_size = sizeof(struct spi_slave),
.probe = tegra210_qspi_probe,
};