[PATCH v7 15/37] drm/tegra: gr3d: Support OPP and power management

Dmitry Osipenko
2021-07-01T23:29:27Z

Add OPP and add PM support to the GR3D driver. This is required for
enabling system-wide DVFS and supporting dynamic power management using
a generic power domain.

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>
---
drivers/gpu/drm/tegra/gr3d.c | 401 ++++++++++++++++++++++++++++++-----
1 file changed, 347 insertions(+), 54 deletions(-)

diff --git a/drivers/gpu/drm/tegra/gr3d.c b/drivers/gpu/drm/tegra/gr3d.c
index 24442ade0da3..b450f1299c3a 100644
--- a/drivers/gpu/drm/tegra/gr3d.c
+++ b/drivers/gpu/drm/tegra/gr3d.c
@@ -5,32 +5,48 @@
*/

#include <linux/clk.h>
+#include <linux/delay.h>
#include <linux/host1x.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_opp.h>
+#include <linux/pm_runtime.h>
#include <linux/reset.h>

+#include <soc/tegra/common.h>
#include <soc/tegra/pmc.h>

#include "drm.h"
#include "gem.h"
#include "gr3d.h"

+enum {
+ RST_GR3D_MC,
+ RST_GR3D,
+ RST_GR3D2_MC,
+ RST_GR3D2,
+ RST_GR3D_MAX,
+};
+
struct gr3d_soc {
unsigned int version;
+ unsigned int num_clocks;
+ unsigned int num_resets;
};

struct gr3d {
struct tegra_drm_client client;
struct host1x_channel *channel;
- struct clk *clk_secondary;
- struct clk *clk;
- struct reset_control *rst_secondary;
- struct reset_control *rst;

const struct gr3d_soc *soc;
+ struct clk_bulk_data *clocks;
+ unsigned int nclocks;
+ struct reset_control_bulk_data resets[RST_GR3D_MAX];
+ unsigned int nresets;
+ bool legacy_pd;

DECLARE_BITMAP(addr_regs, GR3D_NUM_REGS);
};
@@ -109,16 +125,24 @@ static int gr3d_open_channel(struct tegra_drm_client *client,
struct tegra_drm_context *context)
{
struct gr3d *gr3d = to_gr3d(client);
+ int err;

context->channel = host1x_channel_get(gr3d->channel);
if (!context->channel)
return -ENOMEM;

+ err = pm_runtime_resume_and_get(client->base.dev);
+ if (err) {
+ host1x_channel_put(context->channel);
+ return err;
+ }
+
return 0;
}

static void gr3d_close_channel(struct tegra_drm_context *context)
{
+ pm_runtime_put_sync(context->client->base.dev);
host1x_channel_put(context->channel);
}

@@ -155,14 +179,20 @@ static const struct tegra_drm_client_ops gr3d_ops = {

static const struct gr3d_soc tegra20_gr3d_soc = {
.version = 0x20,
+ .num_clocks = 1,
+ .num_resets = 2,
};

static const struct gr3d_soc tegra30_gr3d_soc = {
.version = 0x30,
+ .num_clocks = 2,
+ .num_resets = 4,
};

static const struct gr3d_soc tegra114_gr3d_soc = {
.version = 0x35,
+ .num_clocks = 1,
+ .num_resets = 2,
};

static const struct of_device_id tegra_gr3d_match[] = {
@@ -278,9 +308,138 @@ static const u32 gr3d_addr_regs[] = {
GR3D_GLOBAL_SAMP23SURFADDR(15),
};

+static int gr3d_link_power_domain(struct device *dev, struct device *pd_dev)
+{
+ const u32 link_flags = DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME;
+ struct device_link *link;
+ int err;
+
+ link = device_link_add(dev, pd_dev, link_flags);
+ if (!link) {
+ dev_err(dev, "failed to link to %s\n", dev_name(pd_dev));
+ return -EINVAL;
+ }
+
+ err = devm_add_action_or_reset(dev, (void *)device_link_del, link);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+static int gr3d_init_power(struct device *dev, struct gr3d *gr3d)
+{
+ const char *opp_genpd_names[] = { "3d0", "3d1", NULL };
+ struct device **opp_virt_dev;
+ struct device *pd_dev;
+ unsigned int i;
+ int err;
+
+ err = of_count_phandle_with_args(dev->of_node, "power-domains",
+ "#power-domain-cells");
+ if (err < 0) {
+ if (err != -ENOENT)
+ return err;
+
+ /*
+ * Older device-trees don't use GENPD. In this case we should
+ * toggle power domain manually.
+ */
+ gr3d->legacy_pd = true;
+ return 0;
+ }
+
+ /*
+ * The PM domain core automatically attaches a single power domain,
+ * otherwise it skips attaching completely. We have a single domain
+ * on Tegra20 and two domains on Tegra30+.
+ */
+ if (dev->pm_domain)
+ return 0;
+
+ err = devm_pm_opp_attach_genpd(dev, opp_genpd_names, &opp_virt_dev);
+ if (err)
+ return err;
+
+ for (i = 0; opp_genpd_names[i]; i++) {
+ pd_dev = opp_virt_dev[i];
+ if (!pd_dev) {
+ dev_err(dev, "failed to get %s power domain\n",
+ opp_genpd_names[i]);
+ return -EINVAL;
+ }
+
+ err = gr3d_link_power_domain(dev, pd_dev);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static int gr3d_set_opp(struct dev_pm_set_opp_data *data)
+{
+ struct gr3d *gr3d = dev_get_drvdata(data->dev);
+ unsigned int i;
+ int err;
+
+ for (i = 0; i < gr3d->nclocks; i++) {
+ err = clk_set_rate(gr3d->clocks[i].clk, data->new_opp.rate);
+ if (err) {
+ dev_err(data->dev, "failed to set %s rate to %lu: %d\n",
+ gr3d->clocks[i].id, data->new_opp.rate, err);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int gr3d_get_clocks(struct device *dev, struct gr3d *gr3d)
+{
+ int err;
+
+ err = devm_clk_bulk_get_all(dev, &gr3d->clocks);
+ if (err < 0) {
+ dev_err(dev, "failed to get clock: %d\n", err);
+ return err;
+ }
+ gr3d->nclocks = err;
+
+ if (gr3d->nclocks != gr3d->soc->num_clocks) {
+ dev_err(dev, "invalid number of clocks: %u\n", gr3d->nclocks);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int gr3d_get_resets(struct device *dev, struct gr3d *gr3d)
+{
+ int err;
+
+ gr3d->nresets = gr3d->soc->num_resets;
+ gr3d->resets[RST_GR3D2_MC].id = "mc2";
+ gr3d->resets[RST_GR3D_MC].id = "mc";
+ gr3d->resets[RST_GR3D2].id = "3d2";
+ gr3d->resets[RST_GR3D].id = "3d";
+
+ err = devm_reset_control_bulk_get_optional_exclusive_released(
+ dev, gr3d->nresets, gr3d->resets);
+ if (err) {
+ dev_err(dev, "failed to get reset: %d\n", err);
+ return err;
+ }
+
+ if (WARN_ON(!gr3d->resets[RST_GR3D].rstc) ||
+ WARN_ON(!gr3d->resets[RST_GR3D2].rstc && gr3d->nresets == 4))
+ return -EINVAL;
+
+ return 0;
+}
+
static int gr3d_probe(struct platform_device *pdev)
{
- struct device_node *np = pdev->dev.of_node;
struct host1x_syncpt **syncpts;
struct gr3d *gr3d;
unsigned int i;
@@ -290,56 +449,33 @@ static int gr3d_probe(struct platform_device *pdev)
if (!gr3d)
return -ENOMEM;

+ platform_set_drvdata(pdev, gr3d);
+
gr3d->soc = of_device_get_match_data(&pdev->dev);

syncpts = devm_kzalloc(&pdev->dev, sizeof(*syncpts), GFP_KERNEL);
if (!syncpts)
return -ENOMEM;

- gr3d->clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(gr3d->clk)) {
- dev_err(&pdev->dev, "cannot get clock\n");
- return PTR_ERR(gr3d->clk);
- }
-
- gr3d->rst = devm_reset_control_get(&pdev->dev, "3d");
- if (IS_ERR(gr3d->rst)) {
- dev_err(&pdev->dev, "cannot get reset\n");
- return PTR_ERR(gr3d->rst);
- }
+ err = gr3d_get_clocks(&pdev->dev, gr3d);
+ if (err)
+ return err;

- if (of_device_is_compatible(np, "nvidia,tegra30-gr3d")) {
- gr3d->clk_secondary = devm_clk_get(&pdev->dev, "3d2");
- if (IS_ERR(gr3d->clk_secondary)) {
- dev_err(&pdev->dev, "cannot get secondary clock\n");
- return PTR_ERR(gr3d->clk_secondary);
- }
+ err = gr3d_get_resets(&pdev->dev, gr3d);
+ if (err)
+ return err;

- gr3d->rst_secondary = devm_reset_control_get(&pdev->dev,
- "3d2");
- if (IS_ERR(gr3d->rst_secondary)) {
- dev_err(&pdev->dev, "cannot get secondary reset\n");
- return PTR_ERR(gr3d->rst_secondary);
- }
- }
+ err = gr3d_init_power(&pdev->dev, gr3d);
+ if (err)
+ return err;

- err = tegra_powergate_sequence_power_up(TEGRA_POWERGATE_3D, gr3d->clk,
- gr3d->rst);
- if (err < 0) {
- dev_err(&pdev->dev, "failed to power up 3D unit\n");
+ err = devm_pm_opp_register_set_opp_helper(&pdev->dev, gr3d_set_opp);
+ if (err)
return err;
- }

- if (gr3d->clk_secondary) {
- err = tegra_powergate_sequence_power_up(TEGRA_POWERGATE_3D1,
- gr3d->clk_secondary,
- gr3d->rst_secondary);
- if (err < 0) {
- dev_err(&pdev->dev,
- "failed to power up secondary 3D unit\n");
- return err;
- }
- }
+ err = devm_tegra_core_dev_init_opp_table_simple(&pdev->dev);
+ if (err)
+ return err;

INIT_LIST_HEAD(&gr3d->client.base.list);
gr3d->client.base.ops = &gr3d_client_ops;
@@ -352,20 +488,28 @@ static int gr3d_probe(struct platform_device *pdev)
gr3d->client.version = gr3d->soc->version;
gr3d->client.ops = &gr3d_ops;

+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 200);
+
err = host1x_client_register(&gr3d->client.base);
if (err < 0) {
dev_err(&pdev->dev, "failed to register host1x client: %d\n",
err);
- return err;
+ goto disable_rpm;
}

/* initialize address register map */
for (i = 0; i < ARRAY_SIZE(gr3d_addr_regs); i++)
set_bit(gr3d_addr_regs[i], gr3d->addr_regs);

- platform_set_drvdata(pdev, gr3d);
-
return 0;
+
+disable_rpm:
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return err;
}

static int gr3d_remove(struct platform_device *pdev)
@@ -380,23 +524,172 @@ static int gr3d_remove(struct platform_device *pdev)
return err;
}

- if (gr3d->clk_secondary) {
- reset_control_assert(gr3d->rst_secondary);
- tegra_powergate_power_off(TEGRA_POWERGATE_3D1);
- clk_disable_unprepare(gr3d->clk_secondary);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+static int gr3d_legacy_domain_power_up(struct device *dev, const char *name,
+ unsigned int id)
+{
+ struct gr3d *gr3d = dev_get_drvdata(dev);
+ struct reset_control *reset;
+ struct clk *clk;
+ unsigned int i;
+ int err;
+
+ /*
+ * Tegra20 device-tree doesn't specify 3d clock name and there is only
+ * one clock for Tegra20. Tegra30+ device-trees always specified names
+ * for the clocks.
+ */
+ if (gr3d->nclocks == 1) {
+ if (id == TEGRA_POWERGATE_3D1)
+ return 0;
+
+ clk = gr3d->clocks[0].clk;
+ } else {
+ for (i = 0; i < gr3d->nclocks; i++) {
+ if (WARN_ON_ONCE(!gr3d->clocks[i].id))
+ continue;
+
+ if (!strcmp(gr3d->clocks[i].id, name)) {
+ clk = gr3d->clocks[i].clk;
+ break;
+ }
+ }
+
+ if (WARN_ON_ONCE(i == gr3d->nclocks))
+ return -EINVAL;
+ }
+
+ /*
+ * We use array of resets, which includes MC resets, and MC
+ * reset shouldn't be asserted while hardware is gated because
+ * MC flushing will fail for gated hardware. Hence for legacy
+ * PD we request the individual reset separately.
+ */
+ reset = reset_control_get_exclusive_released(dev, name);
+ if (IS_ERR(reset))
+ return PTR_ERR(reset);
+
+ err = reset_control_acquire(reset);
+ if (err) {
+ dev_err(dev, "failed to acquire %s reset: %d\n", name, err);
+ } else {
+ err = tegra_powergate_sequence_power_up(id, clk, reset);
+ reset_control_release(reset);
}

- reset_control_assert(gr3d->rst);
- tegra_powergate_power_off(TEGRA_POWERGATE_3D);
- clk_disable_unprepare(gr3d->clk);
+ reset_control_put(reset);
+ if (err)
+ return err;
+
+ /*
+ * tegra_powergate_sequence_power_up() leaves clocks enabled
+ * while GENPD not, hence keep clock-enable balanced.
+ */
+ clk_disable_unprepare(clk);

return 0;
}

+static int gr3d_legacy_power_up(struct device *dev)
+{
+ struct gr3d *gr3d = dev_get_drvdata(dev);
+ int err;
+
+ if (gr3d->legacy_pd) {
+ err = gr3d_legacy_domain_power_up(dev, "3d",
+ TEGRA_POWERGATE_3D);
+ if (err)
+ return err;
+
+ err = gr3d_legacy_domain_power_up(dev, "3d2",
+ TEGRA_POWERGATE_3D1);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static int __maybe_unused gr3d_runtime_suspend(struct device *dev)
+{
+ struct gr3d *gr3d = dev_get_drvdata(dev);
+ int err;
+
+ host1x_channel_stop(gr3d->channel);
+
+ err = reset_control_bulk_assert(gr3d->nresets, gr3d->resets);
+ if (err) {
+ dev_err(dev, "failed to assert reset: %d\n", err);
+ return err;
+ }
+
+ usleep_range(10, 20);
+
+ /*
+ * Older device-trees don't specify MC resets and power-gating can't
+ * be done safely in that case. Hence we will keep the power ungated
+ * for older DTBs. For newer DTBs, GENPD will perform the power-gating.
+ */
+
+ clk_bulk_disable_unprepare(gr3d->nclocks, gr3d->clocks);
+ reset_control_bulk_release(gr3d->nresets, gr3d->resets);
+
+ return 0;
+}
+
+static int __maybe_unused gr3d_runtime_resume(struct device *dev)
+{
+ struct gr3d *gr3d = dev_get_drvdata(dev);
+ int err;
+
+ err = gr3d_legacy_power_up(dev);
+ if (err)
+ return err;
+
+ err = reset_control_bulk_acquire(gr3d->nresets, gr3d->resets);
+ if (err) {
+ dev_err(dev, "failed to acquire reset: %d\n", err);
+ return err;
+ }
+
+ err = clk_bulk_prepare_enable(gr3d->nclocks, gr3d->clocks);
+ if (err) {
+ dev_err(dev, "failed to enable clock: %d\n", err);
+ goto release_reset;
+ }
+
+ err = reset_control_bulk_deassert(gr3d->nresets, gr3d->resets);
+ if (err) {
+ dev_err(dev, "failed to deassert reset: %d\n", err);
+ goto disable_clk;
+ }
+
+ return 0;
+
+disable_clk:
+ clk_bulk_disable_unprepare(gr3d->nclocks, gr3d->clocks);
+release_reset:
+ reset_control_bulk_release(gr3d->nresets, gr3d->resets);
+
+ return err;
+}
+
+static const struct dev_pm_ops tegra_gr3d_pm = {
+ SET_RUNTIME_PM_OPS(gr3d_runtime_suspend, gr3d_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+};
+
struct platform_driver tegra_gr3d_driver = {
.driver = {
.name = "tegra-gr3d",
.of_match_table = tegra_gr3d_match,
+ .pm = &tegra_gr3d_pm,
},
.probe = gr3d_probe,
.remove = gr3d_remove,
--
2.30.2