From 2124331411a1ee88437cdd426854253c173464ba Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Thu, 9 Jul 2020 07:51:44 -0700 Subject: [PATCH] spi: spi-qcom-qspi: Avoid clock setting if not needed As per recent changes to the spi-qcom-qspi, now when we set the clock we'll call into the interconnect framework and also call the OPP API. Those are expensive operations. Let's avoid calling them if possible. This has a big impact on getting transfer rates back up to where they were (or maybe slightly better) before those patches landed. Fixes: cff80645d6d3 ("spi: spi-qcom-qspi: Add interconnect support") Signed-off-by: Douglas Anderson Acked-by: Mark Brown Reviewed-by: Rajendra Nayak Tested-by: Rajendra Nayak Reviewed-by: Mukesh Kumar Savaliya Reviewed-by: Akash Asthana Link: https://lore.kernel.org/r/20200709075113.v2.1.Ia7cb4f41ce93d37d0a764b47c8a453ce9e9c70ef@changeid Signed-off-by: Bjorn Andersson --- drivers/spi/spi-qcom-qspi.c | 41 ++++++++++++++++++++++++++++--------- 1 file changed, 31 insertions(+), 10 deletions(-) diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c index 18a59aa23ef8..8fedc605ab7f 100644 --- a/drivers/spi/spi-qcom-qspi.c +++ b/drivers/spi/spi-qcom-qspi.c @@ -144,6 +144,7 @@ struct qcom_qspi { struct icc_path *icc_path_cpu_to_qspi; struct opp_table *opp_table; bool has_opp_table; + unsigned long last_speed; /* Lock to protect data accessed by IRQs */ spinlock_t lock; }; @@ -226,19 +227,13 @@ static void qcom_qspi_handle_err(struct spi_master *master, spin_unlock_irqrestore(&ctrl->lock, flags); } -static int qcom_qspi_transfer_one(struct spi_master *master, - struct spi_device *slv, - struct spi_transfer *xfer) +static int qcom_qspi_set_speed(struct qcom_qspi *ctrl, unsigned long speed_hz) { - struct qcom_qspi *ctrl = spi_master_get_devdata(master); int ret; - unsigned long speed_hz; - unsigned long flags; unsigned int avg_bw_cpu; - speed_hz = slv->max_speed_hz; - if (xfer->speed_hz) - speed_hz = xfer->speed_hz; + if (speed_hz == ctrl->last_speed) + return 0; /* In regular operation (SBL_EN=1) core must be 4x transfer clock */ ret = dev_pm_opp_set_rate(ctrl->dev, speed_hz * 4); @@ -259,6 +254,28 @@ static int qcom_qspi_transfer_one(struct spi_master *master, return ret; } + ctrl->last_speed = speed_hz; + + return 0; +} + +static int qcom_qspi_transfer_one(struct spi_master *master, + struct spi_device *slv, + struct spi_transfer *xfer) +{ + struct qcom_qspi *ctrl = spi_master_get_devdata(master); + int ret; + unsigned long speed_hz; + unsigned long flags; + + speed_hz = slv->max_speed_hz; + if (xfer->speed_hz) + speed_hz = xfer->speed_hz; + + ret = qcom_qspi_set_speed(ctrl, speed_hz); + if (ret) + return ret; + spin_lock_irqsave(&ctrl->lock, flags); /* We are half duplex, so either rx or tx will be set */ @@ -602,7 +619,11 @@ static int __maybe_unused qcom_qspi_runtime_resume(struct device *dev) return ret; } - return clk_bulk_prepare_enable(QSPI_NUM_CLKS, ctrl->clks); + ret = clk_bulk_prepare_enable(QSPI_NUM_CLKS, ctrl->clks); + if (ret) + return ret; + + return dev_pm_opp_set_rate(dev, ctrl->last_speed * 4); } static int __maybe_unused qcom_qspi_suspend(struct device *dev)