On 14/01/2020 07:15, Nicolas Boichat wrote: > Some GPUs, namely, the bifrost/g72 part on MT8183, have a second > regulator for their SRAM, let's add support for that. > > We extend the framework in a generic manner so that we could > support more than 2 regulators, if required. > > Signed-off-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx> > > --- > > v3: > - Make this more generic, by allowing any number of regulators > (in practice we fix the maximum number of regulators to 2, but > this could be increased easily). > - We only probe the second regulator if the device tree matching > data asks for it. > - I couldn't find a way to detect the number of regulators in the > device tree, if we wanted to refuse to probe the device if there > are too many regulators, which might be required for safety, see > the thread on v2 [1]. > - The discussion also included the idea of a separate device tree > entry for a "soft PDC", or at least a separate driver. I'm not > sure to understand the full picture, and how different vendors > implement this, so I'm still integrating everything in the main > driver. I'd be happy to try to make mt8183 fit into such a > framework after it's created, but I don't think I'm best placed > to implement (and again, the main purpose of this was to test > if the binding is correct). >From discussions offline, I think I've come round to the view that having a "soft PDC" in device tree isn't the right solution. Device tree should be describing the hardware and that isn't actually a hardware component. I guess we'll have to wait to see how many devices have a similar 'quirk' and whether it's worth representing this is software in a more generic manner, or if matching on compatible strings will be sufficient for the devices that need multiple regulators. One (minor) comment below, but otherwise LGTM. > > [1] https://patchwork.kernel.org/patch/11322839/ > > drivers/gpu/drm/panfrost/panfrost_device.c | 25 ++++++++++++------- > drivers/gpu/drm/panfrost/panfrost_device.h | 15 +++++++++++- > drivers/gpu/drm/panfrost/panfrost_drv.c | 28 +++++++++++++++------- > 3 files changed, 50 insertions(+), 18 deletions(-) > > diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c > index 238fb6d54df4732..c30e0a3772a4f57 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_device.c > +++ b/drivers/gpu/drm/panfrost/panfrost_device.c > @@ -87,18 +87,26 @@ static void panfrost_clk_fini(struct panfrost_device *pfdev) > > static int panfrost_regulator_init(struct panfrost_device *pfdev) > { > - int ret; > + int ret, i; > > - pfdev->regulator = devm_regulator_get(pfdev->dev, "mali"); > - if (IS_ERR(pfdev->regulator)) { > - ret = PTR_ERR(pfdev->regulator); > - dev_err(pfdev->dev, "failed to get regulator: %d\n", ret); > + BUG_ON(pfdev->comp->num_supplies > ARRAY_SIZE(pfdev->regulators)); > + > + for (i = 0; i < pfdev->comp->num_supplies; i++) { > + pfdev->regulators[i].supply = pfdev->comp->supply_names[i]; > + } > + > + ret = devm_regulator_bulk_get(pfdev->dev, > + pfdev->comp->num_supplies, > + pfdev->regulators); > + if (ret < 0) { > + dev_err(pfdev->dev, "failed to get regulators: %d\n", ret); > return ret; > } > > - ret = regulator_enable(pfdev->regulator); > + ret = regulator_bulk_enable(pfdev->comp->num_supplies, > + pfdev->regulators); > if (ret < 0) { > - dev_err(pfdev->dev, "failed to enable regulator: %d\n", ret); > + dev_err(pfdev->dev, "failed to enable regulators: %d\n", ret); > return ret; > } > > @@ -107,7 +115,8 @@ static int panfrost_regulator_init(struct panfrost_device *pfdev) > > static void panfrost_regulator_fini(struct panfrost_device *pfdev) > { > - regulator_disable(pfdev->regulator); > + regulator_bulk_disable(pfdev->comp->num_supplies, > + pfdev->regulators); > } > > int panfrost_device_init(struct panfrost_device *pfdev) > diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h > index 06713811b92cdf7..021f063ffb3747f 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_device.h > +++ b/drivers/gpu/drm/panfrost/panfrost_device.h > @@ -7,6 +7,7 @@ > > #include <linux/atomic.h> > #include <linux/io-pgtable.h> > +#include <linux/regulator/consumer.h> > #include <linux/spinlock.h> > #include <drm/drm_device.h> > #include <drm/drm_mm.h> > @@ -19,6 +20,7 @@ struct panfrost_job; > struct panfrost_perfcnt; > > #define NUM_JOB_SLOTS 3 > +#define MAX_REGULATORS 2 > > struct panfrost_features { > u16 id; > @@ -51,6 +53,16 @@ struct panfrost_features { > unsigned long hw_issues[64 / BITS_PER_LONG]; > }; > > +/* > + * Features that cannot be automatically detected and need matching using the > + * compatible string, typically SoC-specific. > + */ > +struct panfrost_compatible { > + /* Supplies count and names. */ > + int num_supplies; > + const char * const *supply_names; > +}; > + > struct panfrost_device { > struct device *dev; > struct drm_device *ddev; > @@ -59,10 +71,11 @@ struct panfrost_device { > void __iomem *iomem; > struct clk *clock; > struct clk *bus_clock; > - struct regulator *regulator; > + struct regulator_bulk_data regulators[MAX_REGULATORS]; > struct reset_control *rstc; > > struct panfrost_features features; > + const struct panfrost_compatible* comp; > > spinlock_t as_lock; > unsigned long as_in_use_mask; > diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c > index 48e3c4165247cea..db3563b80150c9d 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_drv.c > +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c > @@ -510,6 +510,10 @@ static int panfrost_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, pfdev); > > + pfdev->comp = of_device_get_match_data(&pdev->dev); > + if (!pfdev->comp) > + return -ENODEV; > + > /* Allocate and initialze the DRM device. */ > ddev = drm_dev_alloc(&panfrost_drm_driver, &pdev->dev); > if (IS_ERR(ddev)) > @@ -581,16 +585,22 @@ static int panfrost_remove(struct platform_device *pdev) > return 0; > } > > +const char * const default_supplies[] = { "mali" }; This should be static. Steve > +static const struct panfrost_compatible default_data = { > + .num_supplies = ARRAY_SIZE(default_supplies), > + .supply_names = default_supplies, > +}; > + > static const struct of_device_id dt_match[] = { > - { .compatible = "arm,mali-t604" }, > - { .compatible = "arm,mali-t624" }, > - { .compatible = "arm,mali-t628" }, > - { .compatible = "arm,mali-t720" }, > - { .compatible = "arm,mali-t760" }, > - { .compatible = "arm,mali-t820" }, > - { .compatible = "arm,mali-t830" }, > - { .compatible = "arm,mali-t860" }, > - { .compatible = "arm,mali-t880" }, > + { .compatible = "arm,mali-t604", .data = &default_data, }, > + { .compatible = "arm,mali-t624", .data = &default_data, }, > + { .compatible = "arm,mali-t628", .data = &default_data, }, > + { .compatible = "arm,mali-t720", .data = &default_data, }, > + { .compatible = "arm,mali-t760", .data = &default_data, }, > + { .compatible = "arm,mali-t820", .data = &default_data, }, > + { .compatible = "arm,mali-t830", .data = &default_data, }, > + { .compatible = "arm,mali-t860", .data = &default_data, }, > + { .compatible = "arm,mali-t880", .data = &default_data, }, > {} > }; > MODULE_DEVICE_TABLE(of, dt_match); >
