Now Internal and External memory controllers are memory interconnection providers. This allows us to use interconnect API for tuning of memory configuration. EMC driver now supports OPPs and DVFS.
Tested-by: Nicolas Chauvet kwizart@gmail.com Signed-off-by: Dmitry Osipenko digetx@gmail.com --- drivers/memory/tegra/Kconfig | 1 + drivers/memory/tegra/tegra124-emc.c | 186 +++++++++++++++++++++++++++- drivers/memory/tegra/tegra124.c | 31 +++++ 3 files changed, 216 insertions(+), 2 deletions(-)
diff --git a/drivers/memory/tegra/Kconfig b/drivers/memory/tegra/Kconfig index 94536dc4c495..3d1ef3ec1a2d 100644 --- a/drivers/memory/tegra/Kconfig +++ b/drivers/memory/tegra/Kconfig @@ -34,6 +34,7 @@ config TEGRA124_EMC tristate "NVIDIA Tegra124 External Memory Controller driver" default y depends on TEGRA_MC && ARCH_TEGRA_124_SOC + select PM_OPP help This driver is for the External Memory Controller (EMC) found on Tegra124 chips. The EMC controls the external DRAM on the board. diff --git a/drivers/memory/tegra/tegra124-emc.c b/drivers/memory/tegra/tegra124-emc.c index 2814b1b4a1d9..bdce7bebe0ef 100644 --- a/drivers/memory/tegra/tegra124-emc.c +++ b/drivers/memory/tegra/tegra124-emc.c @@ -12,17 +12,21 @@ #include <linux/clk/tegra.h> #include <linux/debugfs.h> #include <linux/delay.h> +#include <linux/interconnect-provider.h> #include <linux/io.h> #include <linux/module.h> #include <linux/of_address.h> #include <linux/of_platform.h> #include <linux/platform_device.h> +#include <linux/pm_opp.h> #include <linux/sort.h> #include <linux/string.h>
#include <soc/tegra/fuse.h> #include <soc/tegra/mc.h>
+#include "mc.h" + #define EMC_FBIO_CFG5 0x104 #define EMC_FBIO_CFG5_DRAM_TYPE_MASK 0x3 #define EMC_FBIO_CFG5_DRAM_TYPE_SHIFT 0 @@ -482,6 +486,9 @@ struct tegra_emc { unsigned long min_rate; unsigned long max_rate; } debugfs; + + struct opp_table *opp_table; + struct icc_provider provider; };
/* Timing change sequence functions */ @@ -1177,6 +1184,169 @@ static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc) emc, &tegra_emc_debug_max_rate_fops); }
+static inline struct tegra_emc * +to_tegra_emc_provider(struct icc_provider *provider) +{ + return container_of(provider, struct tegra_emc, provider); +} + +static struct icc_node_data * +emc_of_icc_xlate_extended(struct of_phandle_args *spec, void *data) +{ + struct icc_provider *provider = data; + struct icc_node_data *ndata; + struct icc_node *node; + + /* External Memory is the only possible ICC route */ + list_for_each_entry(node, &provider->nodes, node_list) { + if (node->id != TEGRA_ICC_EMEM) + continue; + + ndata = kzalloc(sizeof(*ndata), GFP_KERNEL); + if (!ndata) + return ERR_PTR(-ENOMEM); + + /* + * SRC and DST nodes should have matching TAG in order to have + * it set by default for a requested path. + */ + ndata->tag = TEGRA_MC_ICC_TAG_ISO; + ndata->node = node; + + return ndata; + } + + return ERR_PTR(-EINVAL); +} + +static int emc_icc_set(struct icc_node *src, struct icc_node *dst) +{ + struct tegra_emc *emc = to_tegra_emc_provider(dst->provider); + unsigned long long peak_bw = icc_units_to_bps(dst->peak_bw); + unsigned long long avg_bw = icc_units_to_bps(dst->avg_bw); + unsigned long long rate = max(avg_bw, peak_bw); + unsigned int dram_data_bus_width_bytes = 8; + unsigned int ddr = 2; + int err; + + /* + * Tegra124 EMC runs on a clock rate of SDRAM bus. This means that + * EMC clock rate is twice smaller than the peak data rate because + * data is sample on both EMC clock edges. + */ + do_div(rate, ddr * dram_data_bus_width_bytes); + rate = min_t(u64, rate, U32_MAX); + + err = dev_pm_opp_set_rate(emc->dev, rate); + if (err) + return err; + + return 0; +} + +static int tegra_emc_interconnect_init(struct tegra_emc *emc) +{ + const struct tegra_mc_soc *soc = emc->mc->soc; + struct icc_node *node; + int err; + + emc->provider.dev = emc->dev; + emc->provider.set = emc_icc_set; + emc->provider.data = &emc->provider; + emc->provider.aggregate = soc->icc_ops->aggregate; + emc->provider.xlate_extended = emc_of_icc_xlate_extended; + + err = icc_provider_add(&emc->provider); + if (err) + goto err_msg; + + /* create External Memory Controller node */ + node = icc_node_create(TEGRA_ICC_EMC); + err = PTR_ERR_OR_ZERO(node); + if (err) + goto del_provider; + + node->name = "External Memory Controller"; + icc_node_add(node, &emc->provider); + + /* link External Memory Controller to External Memory (DRAM) */ + err = icc_link_create(node, TEGRA_ICC_EMEM); + if (err) + goto remove_nodes; + + /* create External Memory node */ + node = icc_node_create(TEGRA_ICC_EMEM); + err = PTR_ERR_OR_ZERO(node); + if (err) + goto remove_nodes; + + node->name = "External Memory (DRAM)"; + icc_node_add(node, &emc->provider); + + return 0; + +remove_nodes: + icc_nodes_remove(&emc->provider); +del_provider: + icc_provider_del(&emc->provider); +err_msg: + dev_err(emc->dev, "failed to initialize ICC: %d\n", err); + + return err; +} + +static int tegra_emc_opp_table_init(struct tegra_emc *emc) +{ + u32 hw_version = BIT(tegra_sku_info.soc_speedo_id); + struct opp_table *opp_table; + const char *rname = "core"; + int err; + + /* + * Legacy device-trees don't have OPP table and EMC driver isn't + * useful in this case. + */ + if (!device_property_present(emc->dev, "operating-points-v2")) { + dev_err(emc->dev, "OPP table not found\n"); + dev_err(emc->dev, "please update your device tree\n"); + return -ENODEV; + } + + /* voltage scaling is optional */ + if (device_property_present(emc->dev, "core-supply")) + emc->opp_table = dev_pm_opp_set_regulators(emc->dev, &rname, 1); + else + emc->opp_table = dev_pm_opp_get_opp_table(emc->dev); + + if (IS_ERR(emc->opp_table)) + return dev_err_probe(emc->dev, PTR_ERR(emc->opp_table), + "failed to prepare OPP table\n"); + + opp_table = dev_pm_opp_set_supported_hw(emc->dev, &hw_version, 1); + err = PTR_ERR_OR_ZERO(opp_table); + if (err) { + dev_err(emc->dev, "failed to set supported HW: %d\n", err); + goto put_table; + } + + err = dev_pm_opp_of_add_table(emc->dev); + if (err) { + dev_err(emc->dev, "failed to add OPP table: %d\n", err); + goto put_hw; + } + + dev_info(emc->dev, "OPP HW ver. 0x%x\n", hw_version); + + return 0; + +put_hw: + dev_pm_opp_put_supported_hw(emc->opp_table); +put_table: + dev_pm_opp_put_opp_table(emc->opp_table); + + return err; +} + static int tegra_emc_probe(struct platform_device *pdev) { struct device_node *np; @@ -1226,14 +1396,20 @@ static int tegra_emc_probe(struct platform_device *pdev) return err; }
- platform_set_drvdata(pdev, emc); - tegra124_clk_set_emc_callbacks(tegra_emc_prepare_timing_change, tegra_emc_complete_timing_change);
+ platform_set_drvdata(pdev, emc); + + err = tegra_emc_opp_table_init(emc); + if (err) + goto unset_cb; + if (IS_ENABLED(CONFIG_DEBUG_FS)) emc_debugfs_init(&pdev->dev, emc);
+ tegra_emc_interconnect_init(emc); + /* * Don't allow the kernel module to be unloaded. Unloading adds some * extra complexity which doesn't really worth the effort in a case of @@ -1242,6 +1418,11 @@ static int tegra_emc_probe(struct platform_device *pdev) try_module_get(THIS_MODULE);
return 0; + +unset_cb: + tegra124_clk_set_emc_callbacks(NULL, NULL); + + return err; };
static struct platform_driver tegra_emc_driver = { @@ -1250,6 +1431,7 @@ static struct platform_driver tegra_emc_driver = { .name = "tegra-emc", .of_match_table = tegra_emc_of_match, .suppress_bind_attrs = true, + .sync_state = icc_sync_state, }, }; module_platform_driver(tegra_emc_driver); diff --git a/drivers/memory/tegra/tegra124.c b/drivers/memory/tegra/tegra124.c index e2389573d3c0..b69d76cd0411 100644 --- a/drivers/memory/tegra/tegra124.c +++ b/drivers/memory/tegra/tegra124.c @@ -1010,6 +1010,35 @@ static const struct tegra_mc_reset tegra124_mc_resets[] = { TEGRA124_MC_RESET(GPU, 0x970, 0x974, 2), };
+static int tegra124_mc_icc_set(struct icc_node *src, struct icc_node *dst) +{ + /* TODO: program PTSA */ + return 0; +} + +static int tegra124_mc_icc_aggreate(struct icc_node *node, u32 tag, u32 avg_bw, + u32 peak_bw, u32 *agg_avg, u32 *agg_peak) +{ + /* + * ISO clients need to reserve extra bandwidth up-front because + * there could high bandwidth pressure during initial fulling-up + * of the client's FIFO buffers. Secondly, we need to take into + * account impurities of the memory subsystem. + */ + if (tag == TEGRA_MC_ICC_TAG_ISO) + peak_bw = tegra_mc_scale_percents(peak_bw, 400); + + *agg_avg += avg_bw; + *agg_peak = max(*agg_peak, peak_bw); + + return 0; +} + +static const struct tegra_mc_icc_ops tegra124_mc_icc_ops = { + .aggregate = tegra124_mc_icc_aggreate, + .set = tegra124_mc_icc_set, +}; + #ifdef CONFIG_ARCH_TEGRA_124_SOC static const unsigned long tegra124_mc_emem_regs[] = { MC_EMEM_ARB_CFG, @@ -1061,6 +1090,7 @@ const struct tegra_mc_soc tegra124_mc_soc = { .reset_ops = &tegra_mc_reset_ops_common, .resets = tegra124_mc_resets, .num_resets = ARRAY_SIZE(tegra124_mc_resets), + .icc_ops = &tegra124_mc_icc_ops, }; #endif /* CONFIG_ARCH_TEGRA_124_SOC */
@@ -1091,5 +1121,6 @@ const struct tegra_mc_soc tegra132_mc_soc = { .reset_ops = &tegra_mc_reset_ops_common, .resets = tegra124_mc_resets, .num_resets = ARRAY_SIZE(tegra124_mc_resets), + .icc_ops = &tegra124_mc_icc_ops, }; #endif /* CONFIG_ARCH_TEGRA_132_SOC */