spi: spi-geni-qcom: Set oversampling based on core revision
The oversampling rate of the core is used in clock related computation.
This rate depends on the core revision. Read the core revision to
determine the oversampling rate.
Change-Id: Ifae791ef0f40acd011b9b19d23ccd77f5aefddd5
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>
diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index ad3eb187..37766d29 100644
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -23,7 +23,6 @@
#define SPI_NUM_CHIPSELECT (4)
#define SPI_XFER_TIMEOUT_MS (250)
-#define SPI_OVERSAMPLING (2)
/* SPI SE specific registers */
#define SE_SPI_CPHA (0x224)
#define SE_SPI_LOOPBACK (0x22C)
@@ -100,6 +99,7 @@
struct spi_transfer *cur_xfer;
struct completion xfer_done;
struct device *wrapper_dev;
+ int oversampling;
};
static struct spi_master *get_spi_master(struct device *dev)
@@ -123,7 +123,8 @@
clk_sel &= ~CLK_SEL_MSK;
m_clk_cfg &= ~CLK_DIV_MSK;
- ret = geni_se_clk_freq_match(&mas->spi_rsc, speed_hz, &idx,
+ ret = geni_se_clk_freq_match(&mas->spi_rsc,
+ (speed_hz * mas->oversampling), &idx,
&sclk_freq, true);
if (ret) {
dev_err(mas->dev, "%s: Failed(%d) to find src clk for 0x%x\n",
@@ -131,17 +132,23 @@
return ret;
}
- div = ((sclk_freq / SPI_OVERSAMPLING) / speed_hz);
- if (!div)
+ div = ((sclk_freq / mas->oversampling) / speed_hz);
+ if (!div) {
+ dev_err(mas->dev, "%s:Err:sclk:%lu oversampling:%d speed:%u\n",
+ __func__, sclk_freq, mas->oversampling, speed_hz);
return -EINVAL;
+ }
dev_dbg(mas->dev, "%s: req %u sclk %lu, idx %d, div %d\n", __func__,
speed_hz, sclk_freq, idx, div);
clk_sel |= (idx & CLK_SEL_MSK);
m_clk_cfg |= ((div << CLK_DIV_SHFT) | SER_CLK_EN);
ret = clk_set_rate(rsc->se_clk, sclk_freq);
- if (ret)
+ if (ret) {
+ dev_err(mas->dev, "%s: clk_set_rate failed %d\n",
+ __func__, ret);
return ret;
+ }
geni_write_reg(clk_sel, mas->base, SE_GENI_CLK_SEL);
geni_write_reg(m_clk_cfg, mas->base, GENI_SER_M_CLK_CFG);
@@ -238,6 +245,10 @@
if (unlikely(!mas->setup)) {
int proto = get_se_proto(mas->base);
+ unsigned int major;
+ unsigned int minor;
+ unsigned int step;
+ int hw_ver;
if (unlikely(proto != SPI)) {
dev_err(mas->dev, "Invalid proto %d\n", proto);
@@ -248,12 +259,24 @@
mas->tx_fifo_depth = get_tx_fifo_depth(mas->base);
mas->rx_fifo_depth = get_rx_fifo_depth(mas->base);
mas->tx_fifo_width = get_tx_fifo_width(mas->base);
+ mas->oversampling = 1;
/* Transmit an entire FIFO worth of data per IRQ */
mas->tx_wm = 1;
dev_dbg(mas->dev, "tx_fifo %d rx_fifo %d tx_width %d\n",
mas->tx_fifo_depth, mas->rx_fifo_depth,
mas->tx_fifo_width);
mas->setup = true;
+ hw_ver = geni_se_qupv3_hw_version(mas->wrapper_dev, &major,
+ &minor, &step);
+ if (hw_ver)
+ dev_err(mas->dev, "%s:Err getting HW version %d\n",
+ __func__, hw_ver);
+ else {
+ dev_dbg(mas->dev, "%s:Major:%d Minor:%d step:%d\n",
+ __func__, major, minor, step);
+ if ((major == 1) && (minor == 0))
+ mas->oversampling = 2;
+ }
}
exit_prepare_transfer_hardware:
return ret;