diff mbox series

[2/4] spi: qup: Parse OPP table for DVFS support

Message ID 20230912-spi-qup-dvfs-v1-2-3e38aa09c2bd@kernkonzept.com (mailing list archive)
State Superseded
Headers show
Series spi: qup: Allow scaling power domains and interconnect | expand

Commit Message

Stephan Gerhold Sept. 12, 2023, 2:30 p.m. UTC 
Parse the OPP table from the device tree and use dev_pm_opp_set_rate()
instead of clk_set_rate() to allow making performance state for power
domains specified in the OPP table.

This is needed to guarantee correct behavior of the clock, especially
with the higher clock/SPI bus frequencies.

Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
---
 drivers/spi/spi-qup.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

Comments

Konrad Dybcio Sept. 13, 2023, 8:54 a.m. UTC | #1 
On 12.09.2023 16:30, Stephan Gerhold wrote:
> Parse the OPP table from the device tree and use dev_pm_opp_set_rate()
> instead of clk_set_rate() to allow making performance state for power
> domains specified in the OPP table.
> 
> This is needed to guarantee correct behavior of the clock, especially
> with the higher clock/SPI bus frequencies.
> 
> Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
> ---
Acked-by: Konrad Dybcio <konrad.dybcio@linaro.org>

Konrad
diff mbox series

Patch

diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
index 4b6f6b25219b..bf043be3a2a9 100644
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -12,6 +12,7 @@ 
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pm_opp.h>
 #include <linux/pm_runtime.h>
 #include <linux/spi/spi.h>
 #include <linux/dmaengine.h>
@@ -667,7 +668,7 @@  static int spi_qup_io_prep(struct spi_device *spi, struct spi_transfer *xfer)
 		return -EIO;
 	}
 
-	ret = clk_set_rate(controller->cclk, xfer->speed_hz);
+	ret = dev_pm_opp_set_rate(controller->dev, xfer->speed_hz);
 	if (ret) {
 		dev_err(controller->dev, "fail to set frequency %d",
 			xfer->speed_hz);
@@ -1027,6 +1028,15 @@  static int spi_qup_probe(struct platform_device *pdev)
 		return -ENXIO;
 	}
 
+	ret = devm_pm_opp_set_clkname(dev, "core");
+	if (ret)
+		return ret;
+
+	/* OPP table is optional */
+	ret = devm_pm_opp_of_add_table(dev);
+	if (ret && ret != -ENODEV)
+		return dev_err_probe(dev, ret, "invalid OPP table\n");
+
 	host = spi_alloc_host(dev, sizeof(struct spi_qup));
 	if (!host) {
 		dev_err(dev, "cannot allocate host\n");