[PATCH V2 4/6] spi: mediatek: add spi memory support
Leilk Liu
leilk.liu at mediatek.com
Tue Feb 22 17:59:50 PST 2022
On Tue, 2022-02-22 at 11:49 +0100, AngeloGioacchino Del Regno wrote:
> Il 21/02/22 05:07, Leilk Liu ha scritto:
> > this patch add the support of spi-mem.
> >
> > Signed-off-by: Leilk Liu <leilk.liu at mediatek.com>
> > ---
> > drivers/spi/spi-mt65xx.c | 310
> > ++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 309 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
> > index 5fa677a589a4..852fc008329a 100644
> > --- a/drivers/spi/spi-mt65xx.c
> > +++ b/drivers/spi/spi-mt65xx.c
> > @@ -17,6 +17,7 @@
> > #include <linux/platform_data/spi-mt65xx.h>
> > #include <linux/pm_runtime.h>
> > #include <linux/spi/spi.h>
> > +#include <linux/spi/spi-mem.h>
> > #include <linux/dma-mapping.h>
> >
> > #define SPI_CFG0_REG 0x0000
> > @@ -75,8 +76,21 @@
> > #define SPI_CMD_IPM_GET_TICKDLY_OFFSET 22
> >
> > #define SPI_CMD_IPM_GET_TICKDLY_MASK GENMASK(24, 22)
> > +
> > +#define PIN_MODE_CFG(x) ((x) / 2)
> > +
> > +#define SPI_CFG3_IPM_PIN_MODE_OFFSET 0
> > #define SPI_CFG3_IPM_HALF_DUPLEX_DIR BIT(2)
> > #define SPI_CFG3_IPM_HALF_DUPLEX_EN BIT(3)
> > +#define SPI_CFG3_IPM_XMODE_EN BIT(4)
> > +#define SPI_CFG3_IPM_NODATA_FLAG BIT(5)
> > +#define SPI_CFG3_IPM_CMD_BYTELEN_OFFSET 8
> > +#define SPI_CFG3_IPM_ADDR_BYTELEN_OFFSET 12
> > +
> > +#define SPI_CFG3_IPM_CMD_PIN_MODE_MASK GENMASK(1, 0)
> > +#define SPI_CFG3_IPM_CMD_BYTELEN_MASK GENMASK(11, 8)
> > +#define SPI_CFG3_IPM_ADDR_BYTELEN_MASK GENMASK(15, 12)
> > +
> > #define MT8173_SPI_MAX_PAD_SEL 3
> >
> > #define MTK_SPI_PAUSE_INT_STATUS 0x2
> > @@ -87,6 +101,8 @@
> > #define MTK_SPI_MAX_FIFO_SIZE 32U
> > #define MTK_SPI_PACKET_SIZE 1024
> > #define MTK_SPI_IPM_PACKET_SIZE SZ_64K
> > +#define MTK_SPI_IPM_PACKET_LOOP SZ_256
> > +
> > #define MTK_SPI_32BITS_MASK (0xffffffff)
> >
> > #define DMA_ADDR_EXT_BITS (36)
> > @@ -104,7 +120,8 @@ struct mtk_spi_compatible {
> > bool no_need_unprepare;
> > /* IPM design improve some single mode features */
> > bool ipm_design;
> > -
> > + /* IPM design that support quad mode */
> > + bool support_quad;
> > };
> >
> > struct mtk_spi {
> > @@ -120,6 +137,11 @@ struct mtk_spi {
> > u32 tx_sgl_len, rx_sgl_len;
> > const struct mtk_spi_compatible *dev_comp;
> > u32 spi_clk_hz;
> > + struct completion spimem_done;
> > + bool use_spimem;
> > + struct device *dev;
> > + dma_addr_t tx_dma;
> > + dma_addr_t rx_dma;
> > };
> >
> > static const struct mtk_spi_compatible mtk_common_compat;
> > @@ -134,6 +156,13 @@ static const struct mtk_spi_compatible
> > ipm_compat_single = {
> > .ipm_design = true,
> > };
> >
> > +static const struct mtk_spi_compatible ipm_compat_quad = {
> > + .enhance_timing = true,
> > + .dma_ext = true,
> > + .ipm_design = true,
> > + .support_quad = true,
> > +};
> > +
> > static const struct mtk_spi_compatible mt6765_compat = {
> > .need_pad_sel = true,
> > .must_tx = true,
> > @@ -178,6 +207,9 @@ static const struct of_device_id
> > mtk_spi_of_match[] = {
> > { .compatible = "mediatek,ipm-spi-single",
> > .data = (void *)&ipm_compat_single,
> > },
> > + { .compatible = "mediatek,ipm-spi-quad",
> > + .data = (void *)&ipm_compat_quad,
> > + },
> > { .compatible = "mediatek,mt2701-spi",
> > .data = (void *)&mtk_common_compat,
> > },
> > @@ -694,6 +726,13 @@ static irqreturn_t mtk_spi_interrupt(int irq,
> > void *dev_id)
> > else
> > mdata->state = MTK_SPI_IDLE;
> >
> > + /* SPI-MEM ops */
> > + if (mdata->use_spimem) {
> > + complete(&mdata->spimem_done);
> > +
> > + return IRQ_HANDLED;
> > + }
> > +
>
> I would instead make a new ISR for the SPI-MEM case... as you're
> bypassing the
> entire mtk_spi_interrupt() function like that.
>
> Example:
>
> static void mtk_spi_check_and_set_state(struct mtk_spi *mdata)
> {
> u32 reg_val;
>
> reg_val = readl(mdata->base + SPI_STATUS0_REG);
>
> if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
>
> mdata->state = MTK_SPI_PAUSED;
>
> else
>
> mdata->state = MTK_SPI_IDLE;
> }
>
> static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
>
> {
> u32 cmd, reg_val, cnt, remainder, len;
>
> struct spi_master *master = dev_id;
>
> struct mtk_spi *mdata = spi_master_get_devdata(master);
>
> struct spi_transfer *trans = mdata->cur_transfer;
>
> mtk_spi_check_and_set_state(mdata);
>
> if (!master->can_dma(........
> .... blurb...
> }
>
> static irqreturn_t mtk_spimem_interrupt(int irq, void *dev_id)
> {
> struct spi_master *master = dev_id;
>
> struct mtk_spi *mdata = spi_master_get_devdata(master);
>
> mtk_spi_check_and_set_state(mdata);
> complete(&mdata->spimem_done);
>
> return IRQ_HANDLED;
> }
>
> ... of course, in mtk_spi_probe(), you would do something like
>
> if (mdata->use_spimem)
> ret = devm_request_irq(&pdev->dev, irq, mtk_spimem_interrupt,
> ...... blah ......
> else
> ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
> ..... blah ......
>
> This way, you're separating the two - increasing human readability
> and showing
> the simplifications (in that regard) in the IPM IP's SPI-MEM
> handling.
>
thanks for your advise, I'll do it in the next version.
> > if (!master->can_dma(master, NULL, trans)) {
> > if (trans->rx_buf) {
> > cnt = mdata->xfer_len / 4;
> > @@ -777,6 +816,266 @@ static irqreturn_t mtk_spi_interrupt(int irq,
> > void *dev_id)
> > return IRQ_HANDLED;
> > }
> >
> > +static int mtk_spi_mem_adjust_op_size(struct spi_mem *mem,
> > + struct spi_mem_op *op)
> > +{
> > + int opcode_len;
> > +
> > + if (op->data.dir != SPI_MEM_NO_DATA) {
> > + opcode_len = 1 + op->addr.nbytes + op->dummy.nbytes;
> > + if (opcode_len + op->data.nbytes >
> > MTK_SPI_IPM_PACKET_SIZE) {
> > + op->data.nbytes = MTK_SPI_IPM_PACKET_SIZE -
> > opcode_len;
> > + /* force data buffer dma-aligned. */
> > + op->data.nbytes -= op->data.nbytes % 4;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static bool mtk_spi_mem_supports_op(struct spi_mem *mem,
> > + const struct spi_mem_op *op)
> > +{
> > + if (op->data.buswidth > 4 || op->addr.buswidth > 4 ||
> > + op->dummy.buswidth > 4 || op->cmd.buswidth > 4)
> > + return false;
> > +
> > + if (op->addr.nbytes && op->dummy.nbytes &&
> > + op->addr.buswidth != op->dummy.buswidth)
> > + return false;
> > +
> > + if (op->addr.nbytes + op->dummy.nbytes > 16)
> > + return false;
> > +
> > + if (op->data.nbytes > MTK_SPI_IPM_PACKET_SIZE) {
> > + if (op->data.nbytes / MTK_SPI_IPM_PACKET_SIZE >
> > + MTK_SPI_IPM_PACKET_LOOP ||
> > + op->data.nbytes % MTK_SPI_IPM_PACKET_SIZE != 0)
> > + return false;
> > + }
> > +
> > + return true;
> > +}
> > +
> > +static void mtk_spi_mem_setup_dma_xfer(struct spi_master *master,
> > + const struct spi_mem_op *op)
> > +{
> > + struct mtk_spi *mdata = spi_master_get_devdata(master);
> > +
> > + writel((u32)(mdata->tx_dma & MTK_SPI_32BITS_MASK),
> > + mdata->base + SPI_TX_SRC_REG);
> > +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
> > + if (mdata->dev_comp->dma_ext)
> > + writel((u32)(mdata->tx_dma >> 32),
> > + mdata->base + SPI_TX_SRC_REG_64);
> > +#endif
> > +
> > + if (op->data.dir == SPI_MEM_DATA_IN) {
> > + writel((u32)(mdata->rx_dma & MTK_SPI_32BITS_MASK),
> > + mdata->base + SPI_RX_DST_REG);
> > +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
> > + if (mdata->dev_comp->dma_ext)
> > + writel((u32)(mdata->rx_dma >> 32),
> > + mdata->base + SPI_RX_DST_REG_64);
> > +#endif
> > + }
> > +}
> > +
> > +static int mtk_spi_transfer_wait(struct spi_mem *mem,
> > + const struct spi_mem_op *op)
> > +{
> > + struct mtk_spi *mdata = spi_master_get_devdata(mem->spi-
> > >master);
> > + unsigned long long ms = 1;
>
> Initializing ms to 1 here is useless, as you're anyway reinitializing
> it
> right after. I would do it as following:
>
> u64 ms = 8000LL;
>
> if (op->data.dir == SPI_MEM_NO_DATA)
> ms *= 32;
> else
> ms *= op->data.nbytes;
>
OK,I'll fix it.
> Besides, can you please add a comment to the code explaining why the
> reason for the waits (why 8, why 1000, why 32)?
>
OK,THANKS
> > +
> > + if (op->data.dir == SPI_MEM_NO_DATA)
> > + ms = 8LL * 1000LL * 32;
> > + else
> > + ms = 8LL * 1000LL * op->data.nbytes;
> > + do_div(ms, mem->spi->max_speed_hz);
>
> I appreciate the usage of safe division helpers, but this is the
> wrong one:
> you have a unsigned long long (64-bits) dividend and a u32 divisor,
> so the
> right function to use here is div_u64().
>
OK, I'll fix it. thanks!
> ms = div_u64(ms, mem->spi->max_speed_hz);
>
> > + ms += ms + 1000; /* 1s tolerance */
> > +
> > + if (ms > UINT_MAX)
> > + ms = UINT_MAX;
> > +
> > + if (!wait_for_completion_timeout(&mdata->spimem_done,
> > + msecs_to_jiffies(ms))) {
> > + dev_err(mdata->dev, "spi-mem transfer timeout\n");
> > + return -ETIMEDOUT;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int mtk_spi_mem_exec_op(struct spi_mem *mem,
> > + const struct spi_mem_op *op)
> > +{
> > + struct mtk_spi *mdata = spi_master_get_devdata(mem->spi-
> > >master);
> > + u32 reg_val, nio = 1, tx_size;
> > + char *tx_tmp_buf, *rx_tmp_buf;
> > + int ret = 0;
> > +
> > + mdata->use_spimem = true;
> > + reinit_completion(&mdata->spimem_done);
> > +
> > + mtk_spi_reset(mdata);
> > + mtk_spi_hw_init(mem->spi->master, mem->spi);
> > + mtk_spi_prepare_transfer(mem->spi->master, mem->spi-
> > >max_speed_hz);
> > +
> > + reg_val = readl(mdata->base + SPI_CFG3_IPM_REG);
> > + /* opcode byte len */
> > + reg_val &= ~SPI_CFG3_IPM_CMD_BYTELEN_MASK;
> > + reg_val |= 1 << SPI_CFG3_IPM_CMD_BYTELEN_OFFSET;
> > +
> > + /* addr & dummy byte len */
> > + reg_val &= ~SPI_CFG3_IPM_ADDR_BYTELEN_MASK;
> > + if (op->addr.nbytes || op->dummy.nbytes)
> > + reg_val |= (op->addr.nbytes + op->dummy.nbytes) <<
> > + SPI_CFG3_IPM_ADDR_BYTELEN_OFFSET;
> > +
> > + /* data byte len */
> > + if (op->data.dir == SPI_MEM_NO_DATA) {
> > + reg_val |= SPI_CFG3_IPM_NODATA_FLAG;
> > + writel(0, mdata->base + SPI_CFG1_REG);
> > + } else {
> > + reg_val &= ~SPI_CFG3_IPM_NODATA_FLAG;
> > + mdata->xfer_len = op->data.nbytes;
> > + mtk_spi_setup_packet(mem->spi->master);
> > + }
> > +
> > + if (op->addr.nbytes || op->dummy.nbytes) {
> > + if (op->addr.buswidth == 1 || op->dummy.buswidth == 1)
> > + reg_val |= SPI_CFG3_IPM_XMODE_EN;
> > + else
> > + reg_val &= ~SPI_CFG3_IPM_XMODE_EN;
> > + }
> > +
> > + if (op->addr.buswidth == 2 ||
> > + op->dummy.buswidth == 2 ||
> > + op->data.buswidth == 2)
> > + nio = 2;
> > + else if (op->addr.buswidth == 4 ||
> > + op->dummy.buswidth == 4 ||
> > + op->data.buswidth == 4)
> > + nio = 4;
>
> else
> nio = 1;
>
> ...so that you can avoid double initialization of the `nio` variable.
>
OK, I'll fix it,thanks
> > +
> > + reg_val &= ~SPI_CFG3_IPM_CMD_PIN_MODE_MASK;
> > + reg_val |= PIN_MODE_CFG(nio) << SPI_CFG3_IPM_PIN_MODE_OFFSET;
> > +
>
> Regards,
> Angelo
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