From e21dd290881b20c9a37e4a79568841e9ffebeb67 Mon Sep 17 00:00:00 2001 From: Steven Price Date: Fri, 16 Aug 2019 10:31:05 +0100 Subject: [PATCH] drm/panfrost: Enable devfreq to work without regulator If there is no regulator defined for the GPU then still control the frequency using the supplied clock. Some boards have clock control but no (direct) control of the regulator. For example the HiKey960 uses a mailbox protocol to a MCU to control frequencies and doesn't directly control the voltage. This patch allows frequency control of the GPU on this system. Signed-off-by: Steven Price Signed-off-by: Rob Herring Link: https://patchwork.freedesktop.org/patch/msgid/20190816093107.30518-1-steven.price@arm.com --- drivers/gpu/drm/panfrost/panfrost_devfreq.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c index a7c18bceb7fd..77e1ad24de53 100644 --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c @@ -39,7 +39,7 @@ static int panfrost_devfreq_target(struct device *dev, unsigned long *freq, * If frequency scaling from low to high, adjust voltage first. * If frequency scaling from high to low, adjust frequency first. */ - if (old_clk_rate < target_rate) { + if (old_clk_rate < target_rate && pfdev->regulator) { err = regulator_set_voltage(pfdev->regulator, target_volt, target_volt); if (err) { @@ -58,7 +58,7 @@ static int panfrost_devfreq_target(struct device *dev, unsigned long *freq, return err; } - if (old_clk_rate > target_rate) { + if (old_clk_rate > target_rate && pfdev->regulator) { err = regulator_set_voltage(pfdev->regulator, target_volt, target_volt); if (err) @@ -136,9 +136,6 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev) int ret; struct dev_pm_opp *opp; - if (!pfdev->regulator) - return 0; - ret = dev_pm_opp_of_add_table(&pfdev->pdev->dev); if (ret == -ENODEV) /* Optional, continue without devfreq */ return 0; -- 2.30.2