// SPDX-License-Identifier: GPL-2.0
/*
* Driver for Atmel QSPI Controller
*
* Copyright (C) 2015 Atmel Corporation
* Copyright (C) 2018 Cryptera A/S
*
* Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
* Author: Piotr Bugalski <bugalski.piotr@gmail.com>
*
* This driver is based on drivers/mtd/spi-nor/fsl-quadspi.c from Freescale.
*/
#include <common.h>
#include <init.h>
#include <driver.h>
#include <errno.h>
#include <clock.h>
#include <xfuncs.h>
#include <gpio.h>
#include <of_gpio.h>
#include <io.h>
#include <spi/spi.h>
#include <mach/iomux.h>
#include <mach/board.h>
#include <mach/cpu.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/spi/spi-mem.h>
#include <of_device.h>
#include <linux/iopoll.h>
#define writel_relaxed writel
#define readl_relaxed readl
/* QSPI register offsets */
#define QSPI_CR 0x0000 /* Control Register */
#define QSPI_MR 0x0004 /* Mode Register */
#define QSPI_RD 0x0008 /* Receive Data Register */
#define QSPI_TD 0x000c /* Transmit Data Register */
#define QSPI_SR 0x0010 /* Status Register */
#define QSPI_IER 0x0014 /* Interrupt Enable Register */
#define QSPI_IDR 0x0018 /* Interrupt Disable Register */
#define QSPI_IMR 0x001c /* Interrupt Mask Register */
#define QSPI_SCR 0x0020 /* Serial Clock Register */
#define QSPI_IAR 0x0030 /* Instruction Address Register */
#define QSPI_ICR 0x0034 /* Instruction Code Register */
#define QSPI_WICR 0x0034 /* Write Instruction Code Register */
#define QSPI_IFR 0x0038 /* Instruction Frame Register */
#define QSPI_RICR 0x003C /* Read Instruction Code Register */
#define QSPI_SMR 0x0040 /* Scrambling Mode Register */
#define QSPI_SKR 0x0044 /* Scrambling Key Register */
#define QSPI_WPMR 0x00E4 /* Write Protection Mode Register */
#define QSPI_WPSR 0x00E8 /* Write Protection Status Register */
#define QSPI_VERSION 0x00FC /* Version Register */
/* Bitfields in QSPI_CR (Control Register) */
#define QSPI_CR_QSPIEN BIT(0)
#define QSPI_CR_QSPIDIS BIT(1)
#define QSPI_CR_SWRST BIT(7)
#define QSPI_CR_LASTXFER BIT(24)
/* Bitfields in QSPI_MR (Mode Register) */
#define QSPI_MR_SMM BIT(0)
#define QSPI_MR_LLB BIT(1)
#define QSPI_MR_WDRBT BIT(2)
#define QSPI_MR_SMRM BIT(3)
#define QSPI_MR_CSMODE_MASK GENMASK(5, 4)
#define QSPI_MR_CSMODE_NOT_RELOADED (0 << 4)
#define QSPI_MR_CSMODE_LASTXFER (1 << 4)
#define QSPI_MR_CSMODE_SYSTEMATICALLY (2 << 4)
#define QSPI_MR_NBBITS_MASK GENMASK(11, 8)
#define QSPI_MR_NBBITS(n) ((((n) - 8) << 8) & QSPI_MR_NBBITS_MASK)
#define QSPI_MR_DLYBCT_MASK GENMASK(23, 16)
#define QSPI_MR_DLYBCT(n) (((n) << 16) & QSPI_MR_DLYBCT_MASK)
#define QSPI_MR_DLYCS_MASK GENMASK(31, 24)
#define QSPI_MR_DLYCS(n) (((n) << 24) & QSPI_MR_DLYCS_MASK)
/* Bitfields in QSPI_SR/QSPI_IER/QSPI_IDR/QSPI_IMR */
#define QSPI_SR_RDRF BIT(0)
#define QSPI_SR_TDRE BIT(1)
#define QSPI_SR_TXEMPTY BIT(2)
#define QSPI_SR_OVRES BIT(3)
#define QSPI_SR_CSR BIT(8)
#define QSPI_SR_CSS BIT(9)
#define QSPI_SR_INSTRE BIT(10)
#define QSPI_SR_QSPIENS BIT(24)
#define QSPI_SR_CMD_COMPLETED (QSPI_SR_INSTRE | QSPI_SR_CSR)
/* Bitfields in QSPI_SCR (Serial Clock Register) */
#define QSPI_SCR_CPOL BIT(0)
#define QSPI_SCR_CPHA BIT(1)
#define QSPI_SCR_SCBR_MASK GENMASK(15, 8)
#define QSPI_SCR_SCBR(n) (((n) << 8) & QSPI_SCR_SCBR_MASK)
#define QSPI_SCR_DLYBS_MASK GENMASK(23, 16)
#define QSPI_SCR_DLYBS(n) (((n) << 16) & QSPI_SCR_DLYBS_MASK)
/* Bitfields in QSPI_ICR (Read/Write Instruction Code Register) */
#define QSPI_ICR_INST_MASK GENMASK(7, 0)
#define QSPI_ICR_INST(inst) (((inst) << 0) & QSPI_ICR_INST_MASK)
#define QSPI_ICR_OPT_MASK GENMASK(23, 16)
#define QSPI_ICR_OPT(opt) (((opt) << 16) & QSPI_ICR_OPT_MASK)
/* Bitfields in QSPI_IFR (Instruction Frame Register) */
#define QSPI_IFR_WIDTH_MASK GENMASK(2, 0)
#define QSPI_IFR_WIDTH_SINGLE_BIT_SPI (0 << 0)
#define QSPI_IFR_WIDTH_DUAL_OUTPUT (1 << 0)
#define QSPI_IFR_WIDTH_QUAD_OUTPUT (2 << 0)
#define QSPI_IFR_WIDTH_DUAL_IO (3 << 0)
#define QSPI_IFR_WIDTH_QUAD_IO (4 << 0)
#define QSPI_IFR_WIDTH_DUAL_CMD (5 << 0)
#define QSPI_IFR_WIDTH_QUAD_CMD (6 << 0)
#define QSPI_IFR_INSTEN BIT(4)
#define QSPI_IFR_ADDREN BIT(5)
#define QSPI_IFR_OPTEN BIT(6)
#define QSPI_IFR_DATAEN BIT(7)
#define QSPI_IFR_OPTL_MASK GENMASK(9, 8)
#define QSPI_IFR_OPTL_1BIT (0 << 8)
#define QSPI_IFR_OPTL_2BIT (1 << 8)
#define QSPI_IFR_OPTL_4BIT (2 << 8)
#define QSPI_IFR_OPTL_8BIT (3 << 8)
#define QSPI_IFR_ADDRL BIT(10)
#define QSPI_IFR_TFRTYP_MEM BIT(12)
#define QSPI_IFR_SAMA5D2_WRITE_TRSFR BIT(13)
#define QSPI_IFR_CRM BIT(14)
#define QSPI_IFR_NBDUM_MASK GENMASK(20, 16)
#define QSPI_IFR_NBDUM(n) (((n) << 16) & QSPI_IFR_NBDUM_MASK)
#define QSPI_IFR_APBTFRTYP_READ BIT(24) /* Defined in SAM9X60 */
/* Bitfields in QSPI_SMR (Scrambling Mode Register) */
#define QSPI_SMR_SCREN BIT(0)
#define QSPI_SMR_RVDIS BIT(1)
/* Bitfields in QSPI_WPMR (Write Protection Mode Register) */
#define QSPI_WPMR_WPEN BIT(0)
#define QSPI_WPMR_WPKEY_MASK GENMASK(31, 8)
#define QSPI_WPMR_WPKEY(wpkey) (((wpkey) << 8) & QSPI_WPMR_WPKEY_MASK)
/* Bitfields in QSPI_WPSR (Write Protection Status Register) */
#define QSPI_WPSR_WPVS BIT(0)
#define QSPI_WPSR_WPVSRC_MASK GENMASK(15, 8)
#define QSPI_WPSR_WPVSRC(src) (((src) << 8) & QSPI_WPSR_WPVSRC)
struct atmel_qspi_caps {
bool has_qspick;
bool has_ricr;
};
struct atmel_qspi {
struct spi_controller ctlr;
void __iomem *regs;
void __iomem *mem;
struct clk *pclk;
struct clk *qspick;
struct platform_device *pdev;
const struct atmel_qspi_caps *caps;
u32 mr;
};
struct atmel_qspi_mode {
u8 cmd_buswidth;
u8 addr_buswidth;
u8 data_buswidth;
u32 config;
};
static const struct atmel_qspi_mode atmel_qspi_modes[] = {
{ 1, 1, 1, QSPI_IFR_WIDTH_SINGLE_BIT_SPI },
{ 1, 1, 2, QSPI_IFR_WIDTH_DUAL_OUTPUT },
{ 1, 1, 4, QSPI_IFR_WIDTH_QUAD_OUTPUT },
{ 1, 2, 2, QSPI_IFR_WIDTH_DUAL_IO },
{ 1, 4, 4, QSPI_IFR_WIDTH_QUAD_IO },
{ 2, 2, 2, QSPI_IFR_WIDTH_DUAL_CMD },
{ 4, 4, 4, QSPI_IFR_WIDTH_QUAD_CMD },
};
static inline bool atmel_qspi_is_compatible(const struct spi_mem_op *op,
const struct atmel_qspi_mode *mode)
{
if (op->cmd.buswidth != mode->cmd_buswidth)
return false;
if (op->addr.nbytes && op->addr.buswidth != mode->addr_buswidth)
return false;
if (op->data.nbytes && op->data.buswidth != mode->data_buswidth)
return false;
return true;
}
static int atmel_qspi_find_mode(const struct spi_mem_op *op)
{
u32 i;
for (i = 0; i < ARRAY_SIZE(atmel_qspi_modes); i++)
if (atmel_qspi_is_compatible(op, &atmel_qspi_modes[i]))
return i;
return -ENOTSUPP;
}
static bool atmel_qspi_supports_op(struct spi_mem *mem,
const struct spi_mem_op *op)
{
if (atmel_qspi_find_mode(op) < 0)
return false;
/* special case not supported by hardware */
if (op->addr.nbytes == 2 && op->cmd.buswidth != op->addr.buswidth &&
op->dummy.nbytes == 0)
return false;
return true;
}
static int atmel_qspi_set_cfg(struct atmel_qspi *aq,
const struct spi_mem_op *op, u32 *offset)
{
u32 iar, icr, ifr;
u32 dummy_cycles = 0;
int mode;
iar = 0;
icr = QSPI_ICR_INST(op->cmd.opcode);
ifr = QSPI_IFR_INSTEN;
mode = atmel_qspi_find_mode(op);
if (mode < 0)
return mode;
ifr |= atmel_qspi_modes[mode].config;
if (op->dummy.buswidth && op->dummy.nbytes)
dummy_cycles = op->dummy.nbytes * 8 / op->dummy.buswidth;
/*
* The controller allows 24 and 32-bit addressing while NAND-flash
* requires 16-bit long. Handling 8-bit long addresses is done using
* the option field. For the 16-bit addresses, the workaround depends
* of the number of requested dummy bits. If there are 8 or more dummy
* cycles, the address is shifted and sent with the first dummy byte.
* Otherwise opcode is disabled and the first byte of the address
* contains the command opcode (works only if the opcode and address
* use the same buswidth). The limitation is when the 16-bit address is
* used without enough dummy cycles and the opcode is using a different
* buswidth than the address.
*/
if (op->addr.buswidth) {
switch (op->addr.nbytes) {
case 0:
break;
case 1:
ifr |= QSPI_IFR_OPTEN | QSPI_IFR_OPTL_8BIT;
icr |= QSPI_ICR_OPT(op->addr.val & 0xff);
break;
case 2:
if (dummy_cycles < 8 / op->addr.buswidth) {
ifr &= ~QSPI_IFR_INSTEN;
ifr |= QSPI_IFR_ADDREN;
iar = (op->cmd.opcode << 16) |
(op->addr.val & 0xffff);
} else {
ifr |= QSPI_IFR_ADDREN;
iar = (op->addr.val << 8) & 0xffffff;
dummy_cycles -= 8 / op->addr.buswidth;
}
break;
case 3:
ifr |= QSPI_IFR_ADDREN;
iar = op->addr.val & 0xffffff;
break;
case 4:
ifr |= QSPI_IFR_ADDREN | QSPI_IFR_ADDRL;
iar = op->addr.val & 0x7ffffff;
break;
default:
return -ENOTSUPP;
}
}
/* offset of the data access in the QSPI memory space */
*offset = iar;
/* Set number of dummy cycles */
if (dummy_cycles)
ifr |= QSPI_IFR_NBDUM(dummy_cycles);
/* Set data enable */
if (op->data.nbytes)
ifr |= QSPI_IFR_DATAEN;
/*
* If the QSPI controller is set in regular SPI mode, set it in
* Serial Memory Mode (SMM).
*/
if (aq->mr != QSPI_MR_SMM) {
writel_relaxed(QSPI_MR_SMM, aq->regs + QSPI_MR);
aq->mr = QSPI_MR_SMM;
}
/* Clear pending interrupts */
(void)readl_relaxed(aq->regs + QSPI_SR);
if (aq->caps->has_ricr) {
if (!op->addr.nbytes && op->data.dir == SPI_MEM_DATA_IN)
ifr |= QSPI_IFR_APBTFRTYP_READ;
/* Set QSPI Instruction Frame registers */
writel_relaxed(iar, aq->regs + QSPI_IAR);
if (op->data.dir == SPI_MEM_DATA_IN)
writel_relaxed(icr, aq->regs + QSPI_RICR);
else
writel_relaxed(icr, aq->regs + QSPI_WICR);
writel_relaxed(ifr, aq->regs + QSPI_IFR);
} else {
if (op->data.dir == SPI_MEM_DATA_OUT)
ifr |= QSPI_IFR_SAMA5D2_WRITE_TRSFR;
/* Set QSPI Instruction Frame registers */
writel_relaxed(iar, aq->regs + QSPI_IAR);
writel_relaxed(icr, aq->regs + QSPI_ICR);
writel_relaxed(ifr, aq->regs + QSPI_IFR);
}
return 0;
}
static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
{
struct atmel_qspi *aq = spi_controller_get_devdata(mem->spi->controller);
u32 sr, imr, offset;
int err;
err = atmel_qspi_set_cfg(aq, op, &offset);
if (err)
return err;
/* Skip to the final steps if there is no data */
if (op->data.nbytes) {
/* Dummy read of QSPI_IFR to synchronize APB and AHB accesses */
(void)readl_relaxed(aq->regs + QSPI_IFR);
/* Send/Receive data */
if (op->data.dir == SPI_MEM_DATA_IN)
memcpy_fromio(op->data.buf.in, aq->mem + offset,
op->data.nbytes);
else
memcpy_toio(aq->mem + offset, op->data.buf.out,
op->data.nbytes);
/* Release the chip-select */
writel_relaxed(QSPI_CR_LASTXFER, aq->regs + QSPI_CR);
}
/* Poll INSTruction End and Chip Select Rise flags. */
imr = QSPI_SR_CMD_COMPLETED;
return readl_poll_timeout(aq->regs + QSPI_SR, sr, (sr & imr) == imr,
1000000);
}
static const char *atmel_qspi_get_name(struct spi_mem *mem)
{
return dev_name(&mem->spi->dev);
}
static const struct spi_controller_mem_ops atmel_qspi_mem_ops = {
.supports_op = atmel_qspi_supports_op,
.exec_op = atmel_qspi_exec_op,
.get_name = atmel_qspi_get_name
};
static int atmel_qspi_setup(struct spi_device *spi)
{
struct atmel_qspi *aq = container_of(spi->controller, struct atmel_qspi,
ctlr);
unsigned long src_rate;
u32 scr, scbr;
if (!spi->max_speed_hz)
return -EINVAL;
src_rate = clk_get_rate(aq->pclk);
if (!src_rate)
return -EINVAL;
/* Compute the QSPI baudrate */
scbr = DIV_ROUND_UP(src_rate, spi->max_speed_hz);
if (scbr > 0)
scbr--;
scr = QSPI_SCR_SCBR(scbr);
writel_relaxed(scr, aq->regs + QSPI_SCR);
return 0;
}
static int atmel_qspi_init(struct atmel_qspi *aq)
{
/* Reset the QSPI controller */
writel_relaxed(QSPI_CR_SWRST, aq->regs + QSPI_CR);
/* Set the QSPI controller by default in Serial Memory Mode */
writel_relaxed(QSPI_MR_SMM, aq->regs + QSPI_MR);
aq->mr = QSPI_MR_SMM;
/* Enable the QSPI controller */
writel_relaxed(QSPI_CR_QSPIEN, aq->regs + QSPI_CR);
return 0;
}
static int atmel_qspi_probe(struct device_d *dev)
{
struct spi_controller *ctrl;
struct atmel_qspi *aq;
int err = 0;
aq = xzalloc(sizeof(*aq));
ctrl = &aq->ctlr;
/* ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD; */
ctrl->dev = dev;
ctrl->setup = atmel_qspi_setup;
ctrl->bus_num = -1;
ctrl->mem_ops = &atmel_qspi_mem_ops;
ctrl->num_chipselect = 1;
spi_controller_set_devdata(ctrl, aq);
/* Map the registers */
aq->regs = dev_request_mem_region_by_name(dev, "qspi_base");
if (IS_ERR(aq->regs)) {
dev_err(dev, "missing registers\n");
err = PTR_ERR(aq->regs);
goto exit;
}
/* Map the AHB memory */
aq->mem = dev_request_mem_region_by_name(dev, "qspi_mmap");
if (IS_ERR(aq->mem)) {
dev_err(dev, "missing AHB memory\n");
err = PTR_ERR(aq->mem);
goto exit;
}
/* Get the peripheral clock */
aq->pclk = clk_get(dev, "pclk");
if (IS_ERR(aq->pclk))
aq->pclk = clk_get(dev, NULL);
if (IS_ERR(aq->pclk)) {
dev_err(dev, "missing peripheral clock\n");
err = PTR_ERR(aq->pclk);
goto exit;
}
/* Enable the peripheral clock */
err = clk_enable(aq->pclk);
if (err) {
dev_err(dev, "failed to enable the peripheral clock\n");
goto exit;
}
aq->caps = of_device_get_match_data(dev);
if (!aq->caps) {
dev_err(dev, "Could not retrieve QSPI caps\n");
err = -EINVAL;
goto exit;
}
if (aq->caps->has_qspick) {
/* Get the QSPI system clock */
aq->qspick = clk_get(dev, "qspick");
if (IS_ERR(aq->qspick)) {
dev_err(dev, "missing system clock\n");
err = PTR_ERR(aq->qspick);
goto disable_pclk;
}
/* Enable the QSPI system clock */
err = clk_enable(aq->qspick);
if (err) {
dev_err(dev, "failed to enable the QSPI system clock\n");
goto disable_pclk;
}
}
err = atmel_qspi_init(aq);
if (err)
goto disable_qspick;
err = spi_register_controller(ctrl);
if (err)
goto disable_qspick;
return 0;
disable_qspick:
clk_disable(aq->qspick);
disable_pclk:
clk_disable(aq->pclk);
exit:
return err;
}
static const struct atmel_qspi_caps atmel_sama5d2_qspi_caps = {};
static const struct atmel_qspi_caps atmel_sam9x60_qspi_caps = {
.has_qspick = true,
.has_ricr = true,
};
static const struct of_device_id atmel_qspi_dt_ids[] = {
{
.compatible = "atmel,sama5d2-qspi",
.data = &atmel_sama5d2_qspi_caps,
},
{
.compatible = "microchip,sam9x60-qspi",
.data = &atmel_sam9x60_qspi_caps,
},
{ /* sentinel */ }
};
static struct driver_d atmel_qspi_driver = {
.name = "atmel_qspi",
.of_compatible = atmel_qspi_dt_ids,
.probe = atmel_qspi_probe,
};
device_platform_driver(atmel_qspi_driver);
