On Monday 08 July 2013 08:02 PM, Felipe Balbi wrote:
Hi,
On Mon, Jul 08, 2013 at 07:12:59PM +0530, Sourav Poddar wrote:
+static inline unsigned long dra7xxx_readl(struct dra7xxx_qspi *qspi,
+ unsigned long reg)
+{
+ return readl(qspi->base + reg);
+}
+
+static inline void dra7xxx_writel(struct dra7xxx_qspi *qspi,
+ unsigned long val, unsigned long reg)
+{
+ writel(val, qspi->base + reg);
+}
+
+static inline unsigned long dra7xxx_readl_data(struct dra7xxx_qspi *qspi,
+ unsigned long reg, int wlen)
+{
+ switch (wlen) {
+ case 8:
+ return readw(qspi->base + reg);
+ break;
+ case 16:
+ return readb(qspi->base + reg);
+ break;
+ case 32:
+ return readl(qspi->base + reg);
+ break;
+ default:
+ return -1;
return -EINVAL ? or some other error code ?
Ok.will change.
+ }
+}
+
+static inline void dra7xxx_writel_data(struct dra7xxx_qspi *qspi,
+ unsigned long val, unsigned long reg, int wlen)
+{
+ switch (wlen) {
+ case 8:
+ writew(val, qspi->base + reg);
+ break;
+ case 16:
+ writeb(val, qspi->base + reg);
+ break;
+ case 32:
+ writeb(val, qspi->base + reg);
+ break;
+ default:
+ dev_dbg(qspi->dev, "word lenght out of range");
+ break;
+ }
+}
+
+static int dra7xxx_qspi_setup(struct spi_device *spi)
+{
+ struct dra7xxx_qspi *qspi = spi_master_get_devdata(spi->master);
+ int clk_div = 0;
+ u32 clk_ctrl_reg, clk_rate;
+
+ clk_rate = clk_get_rate(qspi->fclk);
+
+ if (!qspi->spi_max_frequency) {
+ dev_err(qspi->dev, "spi max frequency not defined\n");
+ return -1;
same here
Ok.
+ } else
this needs to have curly braces too, per CodingStyle
hmm..will change.
+ clk_div = (clk_rate / qspi->spi_max_frequency) - 1;
+
+ dev_dbg(qspi->dev, "%s: hz: %d, clock divider %d\n", __func__,
+ qspi->spi_max_frequency, clk_div);
+
+ pm_runtime_get_sync(qspi->dev);
+
+ clk_ctrl_reg = dra7xxx_readl(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
+
+ clk_ctrl_reg&= ~QSPI_CLK_EN;
+
+ /* disable SCLK */
+ dra7xxx_writel(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
+
+ if (clk_div< 0) {
+ dev_dbg(qspi->dev, "%s: clock divider< 0, using /1 divider\n",
+ __func__);
+ clk_div = 1;
+ }
+
+ if (clk_div> QSPI_CLK_DIV_MAX) {
+ dev_dbg(qspi->dev, "%s: clock divider>%d , using /%d divider\n",
+ __func__, QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
+ clk_div = QSPI_CLK_DIV_MAX;
+ }
+
+ /* enable SCLK */
+ dra7xxx_writel(qspi, QSPI_CLK_EN | clk_div, QSPI_SPI_CLOCK_CNTRL_REG);
+
+ pm_runtime_mark_last_busy(qspi->dev);
+ pm_runtime_put_autosuspend(qspi->dev);
+
+ return 0;
+}
+
+static int dra7xxx_qspi_prepare_xfer(struct spi_master *master)
+{
+ struct dra7xxx_qspi *qspi = spi_master_get_devdata(master);
+
+ pm_runtime_get_sync(qspi->dev);
not going to check return value ?
Will add.
+ return 0;
+}
+
+static int dra7xxx_qspi_unprepare_xfer(struct spi_master *master)
+{
+ struct dra7xxx_qspi *qspi = spi_master_get_devdata(master);
+
+ pm_runtime_mark_last_busy(qspi->dev);
+ pm_runtime_put_autosuspend(qspi->dev);
what about on these two ?
Yes, will add error checking.
+ return 0;
+}
+
+static int qspi_write_msg(struct dra7xxx_qspi *qspi, struct spi_transfer *t)
+{
+ const u8 *txbuf;
+ int wlen, count;
+
+ count = t->len;
+ txbuf = t->tx_buf;
+ wlen = t->bits_per_word;
+
+ while (count--) {
+ dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
+ qspi->cmd | QSPI_WR_SNGL, qspi->dc, *txbuf);
+ dra7xxx_writel(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG);
you should enable the interrupt as the last step. Also, why aren't you
using frame interrupt ?
+ dra7xxx_writel_data(qspi, *txbuf++, QSPI_SPI_DATA_REG, wlen);
+ dra7xxx_writel(qspi, qspi->dc, QSPI_SPI_DC_REG);
+ dra7xxx_writel(qspi, qspi->cmd | QSPI_WR_SNGL,
+ QSPI_SPI_CMD_REG);
+ wait_for_completion(&qspi->word_complete);
+ }
+
+ return 0;
+}
+
+static int qspi_read_msg(struct dra7xxx_qspi *qspi, struct spi_transfer *t)
+{
+ u8 *rxbuf;
+ int wlen, count;
+
+ count = t->len;
+ rxbuf = t->rx_buf;
+ wlen = t->bits_per_word;
+
+ while (count--) {
+ dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n",
+ qspi->cmd | QSPI_RD_SNGL, qspi->dc);
+ dra7xxx_writel(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG);
ditto
hmm. will move this down.
+ dra7xxx_writel(qspi, qspi->dc, QSPI_SPI_DC_REG);
+ dra7xxx_writel(qspi, qspi->cmd | QSPI_RD_SNGL,
+ QSPI_SPI_CMD_REG);
+ wait_for_completion(&qspi->word_complete);
+ *rxbuf++ = dra7xxx_readl_data(qspi, QSPI_SPI_DATA_REG, wlen);
+ dev_dbg(qspi->dev, "rx done, read %02x\n", *(rxbuf-1));
+ }
+
+ return 0;
+}
+
+static int qspi_transfer_msg(struct dra7xxx_qspi *qspi, struct spi_transfer *t)
+{
+ if (t->tx_buf)
+ qspi_write_msg(qspi, t);
+ if (t->rx_buf)
+ qspi_read_msg(qspi, t);
+
+ return 0;
+}
+
+static int dra7xxx_qspi_start_transfer_one(struct spi_master *master,
+ struct spi_message *m)
+{
+ struct dra7xxx_qspi *qspi = spi_master_get_devdata(master);
+ struct spi_device *spi = m->spi;
+ struct spi_transfer *t;
+ int status = 0;
+ int frame_length;
+
+ /* setup device control reg */
+ qspi->dc = 0;
+
+ if (spi->mode& SPI_CPHA)
+ qspi->dc |= QSPI_CKPHA(spi->chip_select);
+ if (spi->mode& SPI_CPOL)
+ qspi->dc |= QSPI_CKPOL(spi->chip_select);
+ if (spi->mode& SPI_CS_HIGH)
+ qspi->dc |= QSPI_CSPOL(spi->chip_select);
+
+ frame_length = DIV_ROUND_UP(m->frame_length * spi->bits_per_word,
why this multiplication ? Frame is not counted in bits but in number of
words. Which means that m->framelength / spi->bits_per_word should be
enough.
Yes, got confused here. Will change.
Also, this actually brings up a mistake I made, if I read the TRM
correclty this time, frame length is nothing but the t->len which
renders patch 1 in this series unnecessary, my mistake.
If flen is t->len, then
1.) yes patch 1 is useles.
2.) frame interrupt will make more sense then.
Till now, we were using flen as sum of all transfers, because of
which
I was forced to check for word complete.
I will check on "flen" and will get back on frame interrupt with
experimental results.
+ spi->bits_per_word);
+
+ frame_length = clamp(frame_length, 0, QSPI_FRAME_MAX);
+
+ /* setup command reg */
+ qspi->cmd = 0;
+ qspi->cmd |= QSPI_EN_CS(spi->chip_select);
+ qspi->cmd |= QSPI_FLEN(frame_length);
right, right, so far so good...
+ list_for_each_entry(t,&m->transfers, transfer_list) {
+ qspi->cmd |= QSPI_WLEN(t->bits_per_word);
sure about this ? according to TRM a write of 0 means 1 bit, 1, means 2
bits, 2 means 3 bits, etc... So this should be t->bits_per_word - 1.
QSPI_WLEN is taking care of subtrating it by -1.
+ qspi->cmd |= QSPI_WC_CMD_INT_EN;
... but why are you still interrupting on every word ????
as I said before, we want to interrupt on every frame. one spi_transfer
is one frame, if that frame has a length of 1MiB, I want to be
interrupted after 1MiB.
+ qspi_transfer_msg(qspi, t);
+ m->actual_length += t->len;
+
+ if (list_is_last(&t->transfer_list,&m->transfers))
+ goto out;
+ }
+
+out:
+ m->status = status;
+ spi_finalize_current_message(master);
+
+ dra7xxx_writel(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
+
+ return status;
+}
+
+static irqreturn_t dra7xxx_qspi_isr(int irq, void *dev_id)
+{
+ struct dra7xxx_qspi *qspi = dev_id;
+ u16 mask, stat;
+
+ irqreturn_t ret = IRQ_HANDLED;
+
+ spin_lock(&qspi->lock);
+
+ stat = dra7xxx_readl(qspi, QSPI_SPI_STATUS_REG);
+ mask = dra7xxx_readl(qspi, QSPI_SPI_CMD_REG);
+
+ if ((stat& QSPI_WC)&& (mask& QSPI_WC_CMD_INT_EN))
this is wrong, everytime you want to handle another IRQ bit, you will
have to update this line.
if (stat& mask)
sounds like it's enough
Yes, correct will change.
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