On Mon, 27 Sept 2021 at 00:42, Dmitry Osipenko digetx@gmail.com wrote:
Add runtime PM and OPP support to the Host1x driver. For the starter we will keep host1x always-on because dynamic power management require a major refactoring of the driver code since lot's of code paths are missing the RPM handling and we're going to remove some of these paths in the future.
Tested-by: Peter Geis pgwipeout@gmail.com # Ouya T30 Tested-by: Paul Fertser fercerpav@gmail.com # PAZ00 T20 Tested-by: Nicolas Chauvet kwizart@gmail.com # PAZ00 T20 and TK1 T124 Tested-by: Matt Merhar mattmerhar@protonmail.com # Ouya T30 Signed-off-by: Dmitry Osipenko digetx@gmail.com
[...]
--- a/drivers/gpu/host1x/dev.c +++ b/drivers/gpu/host1x/dev.c @@ -6,14 +6,18 @@ */
#include <linux/clk.h> +#include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/io.h> #include <linux/list.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/of.h> +#include <linux/pm_runtime.h> #include <linux/slab.h>
+#include <soc/tegra/common.h>
#define CREATE_TRACE_POINTS #include <trace/events/host1x.h> #undef CREATE_TRACE_POINTS @@ -190,6 +194,9 @@ static void host1x_setup_sid_table(struct host1x *host) const struct host1x_info *info = host->info; unsigned int i;
if (!info->has_hypervisor)return;for (i = 0; i < info->num_sid_entries; i++) { const struct host1x_sid_entry *entry = &info->sid_table[i];@@ -347,6 +354,27 @@ static void host1x_iommu_exit(struct host1x *host) } }
+static int host1x_get_resets(struct host1x *host) +{
int err;host->resets[0].id = "mc";host->resets[1].id = "host1x";host->nresets = ARRAY_SIZE(host->resets);err = devm_reset_control_bulk_get_optional_exclusive_released(host->dev, host->nresets, host->resets);if (err) {dev_err(host->dev, "failed to get reset: %d\n", err);return err;}if (WARN_ON(!host->resets[1].rstc))return -ENOENT;return 0;+}
static int host1x_probe(struct platform_device *pdev) { struct host1x *host; @@ -423,12 +451,9 @@ static int host1x_probe(struct platform_device *pdev) return err; }
host->rst = devm_reset_control_get(&pdev->dev, "host1x");if (IS_ERR(host->rst)) {err = PTR_ERR(host->rst);dev_err(&pdev->dev, "failed to get reset: %d\n", err);
err = host1x_get_resets(host);if (err) return err;
} err = host1x_iommu_init(host); if (err < 0) {@@ -443,22 +468,10 @@ static int host1x_probe(struct platform_device *pdev) goto iommu_exit; }
err = clk_prepare_enable(host->clk);if (err < 0) {dev_err(&pdev->dev, "failed to enable clock\n");goto free_channels;}err = reset_control_deassert(host->rst);if (err < 0) {dev_err(&pdev->dev, "failed to deassert reset: %d\n", err);goto unprepare_disable;}err = host1x_syncpt_init(host); if (err) { dev_err(&pdev->dev, "failed to initialize syncpts\n");goto reset_assert;
goto free_channels; } err = host1x_intr_init(host, syncpt_irq);@@ -467,10 +480,18 @@ static int host1x_probe(struct platform_device *pdev) goto deinit_syncpt; }
host1x_debug_init(host);
pm_runtime_enable(&pdev->dev);err = devm_tegra_core_dev_init_opp_table_common(&pdev->dev);if (err)goto pm_disable;
if (host->info->has_hypervisor)host1x_setup_sid_table(host);
/* the driver's code isn't ready yet for the dynamic RPM */err = pm_runtime_resume_and_get(&pdev->dev);if (err)goto pm_disable;host1x_debug_init(host); err = host1x_register(host); if (err < 0)@@ -486,13 +507,14 @@ static int host1x_probe(struct platform_device *pdev) host1x_unregister(host); deinit_debugfs: host1x_debug_deinit(host);
pm_runtime_put(&pdev->dev);
pm_runtime_put() is asynchronous, so it may not actually succeed to trigger the ->runtime_suspend() callback to be invoked. Thus, this could end up that we leave clocks prepared/enabled when ->probe() fails, for example.
I guess pm_runtime_put_sync_suspend() is slightly better.
Another option is to call pm_runtime_force_suspend(), but then you must skip the call pm_runtime_disable() afterwards, as that has already been done inside that function.
+pm_disable:
pm_runtime_disable(&pdev->dev);host1x_intr_deinit(host);deinit_syncpt: host1x_syncpt_deinit(host); -reset_assert:
reset_control_assert(host->rst);-unprepare_disable:
clk_disable_unprepare(host->clk);free_channels: host1x_channel_list_free(&host->channel_list); iommu_exit: @@ -507,19 +529,94 @@ static int host1x_remove(struct platform_device *pdev)
host1x_unregister(host); host1x_debug_deinit(host);
pm_runtime_put(&pdev->dev);
Similar comment as in ->probe().
pm_runtime_disable(&pdev->dev);host1x_intr_deinit(host); host1x_syncpt_deinit(host);
reset_control_assert(host->rst);clk_disable_unprepare(host->clk); host1x_iommu_exit(host); return 0;}
host1x_setup_sid_table(host);host1x_syncpt_restore(host);host1x_intr_start(host);return 0;+disable_clk:
clk_disable_unprepare(host->clk);+release_reset:
reset_control_bulk_release(host->nresets, host->resets);return err;+}
+static const struct dev_pm_ops host1x_pm = {
SET_RUNTIME_PM_OPS(host1x_runtime_suspend, host1x_runtime_resume,NULL)/* TODO: add system suspend-resume once driver will be ready for that */+};
[...]
Kind regards Uffe