Add initial OPP and SoC core voltage scaling support to the Host1x driver. This is required for enabling system-wide DVFS on older Tegra SoCs.
Tested-by: Peter Geis pgwipeout@gmail.com Tested-by: Nicolas Chauvet kwizart@gmail.com Signed-off-by: Dmitry Osipenko digetx@gmail.com --- drivers/gpu/host1x/Kconfig | 1 + drivers/gpu/host1x/dev.c | 87 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 88 insertions(+)
diff --git a/drivers/gpu/host1x/Kconfig b/drivers/gpu/host1x/Kconfig index 6dab94adf25e..fba4207c35a4 100644 --- a/drivers/gpu/host1x/Kconfig +++ b/drivers/gpu/host1x/Kconfig @@ -3,6 +3,7 @@ config TEGRA_HOST1X tristate "NVIDIA Tegra host1x driver" depends on ARCH_TEGRA || (ARM && COMPILE_TEST) select IOMMU_IOVA + select PM_OPP help Driver for the NVIDIA Tegra host1x hardware.
diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c index d0ebb70e2fdd..06e65dc1ab19 100644 --- a/drivers/gpu/host1x/dev.c +++ b/drivers/gpu/host1x/dev.c @@ -13,6 +13,9 @@ #include <linux/of_device.h> #include <linux/of.h> #include <linux/slab.h> +#include <linux/pm_opp.h> + +#include <soc/tegra/fuse.h>
#define CREATE_TRACE_POINTS #include <trace/events/host1x.h> @@ -341,6 +344,85 @@ static void host1x_iommu_exit(struct host1x *host) } }
+static void host1x_deinit_opp_table(void *data) +{ + struct device *dev = data; + struct opp_table *opp_table; + + opp_table = dev_pm_opp_get_opp_table(dev); + dev_pm_opp_of_remove_table(dev); + dev_pm_opp_put_supported_hw(opp_table); + dev_pm_opp_put_regulators(opp_table); + dev_pm_opp_put_opp_table(opp_table); +} + +static int devm_host1x_init_opp_table(struct host1x *host) +{ + struct opp_table *opp_table, *hw_opp_table; + const char *rname = "core"; + u32 hw_version; + int err; + + /* voltage scaling is optional */ + if (device_property_present(host->dev, "core-supply")) + opp_table = dev_pm_opp_set_regulators(host->dev, &rname, 1); + else + opp_table = dev_pm_opp_get_opp_table(host->dev); + + if (IS_ERR(opp_table)) + return dev_err_probe(host->dev, PTR_ERR(opp_table), + "failed to prepare OPP table\n"); + + if (of_machine_is_compatible("nvidia,tegra20")) + hw_version = BIT(tegra_sku_info.soc_process_id); + else + hw_version = BIT(tegra_sku_info.soc_speedo_id); + + hw_opp_table = dev_pm_opp_set_supported_hw(host->dev, &hw_version, 1); + err = PTR_ERR_OR_ZERO(hw_opp_table); + if (err) { + dev_err(host->dev, "failed to set supported HW: %d\n", err); + goto put_table; + } + + /* + * OPP table presence is optional and we want the set_rate() of OPP + * API to work similarly to clk_set_rate() if table is missing in a + * device-tree. The add_table() errors out if OPP is missing in DT. + */ + if (device_property_present(host->dev, "operating-points-v2")) { + err = dev_pm_opp_of_add_table(host->dev); + if (err) { + dev_err(host->dev, "failed to add OPP table: %d\n", err); + goto put_hw; + } + } + + /* first dummy rate-set initializes voltage vote */ + err = dev_pm_opp_set_rate(host->dev, clk_get_rate(host->clk)); + if (err) { + dev_err(host->dev, "failed to initialize OPP clock: %d\n", err); + goto remove_table; + } + + err = devm_add_action(host->dev, host1x_deinit_opp_table, host->dev); + if (err) + goto remove_table; + + dev_info(host->dev, "OPP HW ver. 0x%x\n", hw_version); + + return 0; + +remove_table: + dev_pm_opp_of_remove_table(host->dev); +put_hw: + dev_pm_opp_put_supported_hw(opp_table); +put_table: + dev_pm_opp_put_regulators(opp_table); + + return err; +} + static int host1x_probe(struct platform_device *pdev) { struct host1x *host; @@ -424,6 +506,11 @@ static int host1x_probe(struct platform_device *pdev) return err; }
+ err = devm_host1x_init_opp_table(host); + if (err < 0) + return dev_err_probe(&pdev->dev, err, + "failed to initialize OPP\n"); + err = host1x_iommu_init(host); if (err < 0) { dev_err(&pdev->dev, "failed to setup IOMMU: %d\n", err);