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 | 325 +++++++++++++++++++++++++++- drivers/memory/tegra/tegra124.c | 82 ++++++- 3 files changed, 396 insertions(+), 12 deletions(-)
diff --git a/drivers/memory/tegra/Kconfig b/drivers/memory/tegra/Kconfig index f5b451403c58..a70967a56e52 100644 --- a/drivers/memory/tegra/Kconfig +++ b/drivers/memory/tegra/Kconfig @@ -36,6 +36,7 @@ config TEGRA124_EMC default y depends on TEGRA_MC && ARCH_TEGRA_124_SOC select TEGRA124_CLK_EMC + 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 8fb8c1af25c9..ed34ca982364 100644 --- a/drivers/memory/tegra/tegra124-emc.c +++ b/drivers/memory/tegra/tegra124-emc.c @@ -12,20 +12,26 @@ #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/mutex.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 +#define EMC_FBIO_CFG5_DRAM_WIDTH_X64 BIT(4)
#define EMC_INTSTATUS 0x0 #define EMC_INTSTATUS_CLKCHANGE_COMPLETE BIT(4) @@ -461,6 +467,17 @@ struct emc_timing { u32 emc_zcal_interval; };
+enum emc_rate_request_type { + EMC_RATE_DEBUG, + EMC_RATE_ICC, + EMC_RATE_TYPE_MAX, +}; + +struct emc_rate_request { + unsigned long min_rate; + unsigned long max_rate; +}; + struct tegra_emc { struct device *dev;
@@ -471,6 +488,7 @@ struct tegra_emc { struct clk *clk;
enum emc_dram_type dram_type; + unsigned int dram_bus_width; unsigned int dram_num;
struct emc_timing last_timing; @@ -482,6 +500,17 @@ struct tegra_emc { unsigned long min_rate; unsigned long max_rate; } debugfs; + + struct icc_provider provider; + + /* + * There are multiple sources in the EMC driver which could request + * a min/max clock rate, these rates are contained in this array. + */ + struct emc_rate_request requested_rate[EMC_RATE_TYPE_MAX]; + + /* protect shared rate-change code path */ + struct mutex rate_lock; };
/* Timing change sequence functions */ @@ -870,6 +899,14 @@ static void emc_read_current_timing(struct tegra_emc *emc, static int emc_init(struct tegra_emc *emc) { emc->dram_type = readl(emc->regs + EMC_FBIO_CFG5); + + if (emc->dram_type & EMC_FBIO_CFG5_DRAM_WIDTH_X64) + emc->dram_bus_width = 64; + else + emc->dram_bus_width = 32; + + dev_info(emc->dev, "%ubit DRAM bus\n", emc->dram_bus_width); + emc->dram_type &= EMC_FBIO_CFG5_DRAM_TYPE_MASK; emc->dram_type >>= EMC_FBIO_CFG5_DRAM_TYPE_SHIFT;
@@ -1009,6 +1046,83 @@ tegra_emc_find_node_by_ram_code(struct device_node *node, u32 ram_code) return NULL; }
+static void tegra_emc_rate_requests_init(struct tegra_emc *emc) +{ + unsigned int i; + + for (i = 0; i < EMC_RATE_TYPE_MAX; i++) { + emc->requested_rate[i].min_rate = 0; + emc->requested_rate[i].max_rate = ULONG_MAX; + } +} + +static int emc_request_rate(struct tegra_emc *emc, + unsigned long new_min_rate, + unsigned long new_max_rate, + enum emc_rate_request_type type) +{ + struct emc_rate_request *req = emc->requested_rate; + unsigned long min_rate = 0, max_rate = ULONG_MAX; + unsigned int i; + int err; + + /* select minimum and maximum rates among the requested rates */ + for (i = 0; i < EMC_RATE_TYPE_MAX; i++, req++) { + if (i == type) { + min_rate = max(new_min_rate, min_rate); + max_rate = min(new_max_rate, max_rate); + } else { + min_rate = max(req->min_rate, min_rate); + max_rate = min(req->max_rate, max_rate); + } + } + + if (min_rate > max_rate) { + dev_err_ratelimited(emc->dev, "%s: type %u: out of range: %lu %lu\n", + __func__, type, min_rate, max_rate); + return -ERANGE; + } + + /* + * EMC rate-changes should go via OPP API because it manages voltage + * changes. + */ + err = dev_pm_opp_set_rate(emc->dev, min_rate); + if (err) + return err; + + emc->requested_rate[type].min_rate = new_min_rate; + emc->requested_rate[type].max_rate = new_max_rate; + + return 0; +} + +static int emc_set_min_rate(struct tegra_emc *emc, unsigned long rate, + enum emc_rate_request_type type) +{ + struct emc_rate_request *req = &emc->requested_rate[type]; + int ret; + + mutex_lock(&emc->rate_lock); + ret = emc_request_rate(emc, rate, req->max_rate, type); + mutex_unlock(&emc->rate_lock); + + return ret; +} + +static int emc_set_max_rate(struct tegra_emc *emc, unsigned long rate, + enum emc_rate_request_type type) +{ + struct emc_rate_request *req = &emc->requested_rate[type]; + int ret; + + mutex_lock(&emc->rate_lock); + ret = emc_request_rate(emc, req->min_rate, rate, type); + mutex_unlock(&emc->rate_lock); + + return ret; +} + /* * debugfs interface * @@ -1081,7 +1195,7 @@ static int tegra_emc_debug_min_rate_set(void *data, u64 rate) if (!tegra_emc_validate_rate(emc, rate)) return -EINVAL;
- err = clk_set_min_rate(emc->clk, rate); + err = emc_set_min_rate(emc, rate, EMC_RATE_DEBUG); if (err < 0) return err;
@@ -1111,7 +1225,7 @@ static int tegra_emc_debug_max_rate_set(void *data, u64 rate) if (!tegra_emc_validate_rate(emc, rate)) return -EINVAL;
- err = clk_set_max_rate(emc->clk, rate); + err = emc_set_max_rate(emc, rate, EMC_RATE_DEBUG); if (err < 0) return err;
@@ -1129,15 +1243,6 @@ static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc) unsigned int i; int err;
- emc->clk = devm_clk_get(dev, "emc"); - if (IS_ERR(emc->clk)) { - if (PTR_ERR(emc->clk) != -ENODEV) { - dev_err(dev, "failed to get EMC clock: %ld\n", - PTR_ERR(emc->clk)); - return; - } - } - emc->debugfs.min_rate = ULONG_MAX; emc->debugfs.max_rate = 0;
@@ -1177,6 +1282,182 @@ 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(-EPROBE_DEFER); +} + +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; + const 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 sampled on both EMC clock edges. + */ + dram_data_bus_width_bytes = emc->dram_bus_width / 8; + do_div(rate, ddr * dram_data_bus_width_bytes); + rate = min_t(u64, rate, U32_MAX); + + err = emc_set_min_rate(emc, rate, EMC_RATE_ICC); + 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); + if (IS_ERR(node)) { + err = PTR_ERR(node); + 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); + if (IS_ERR(node)) { + err = PTR_ERR(node); + 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 *clk_opp_table, *hw_opp_table; + int err; + + clk_opp_table = dev_pm_opp_set_clkname(emc->dev, NULL); + err = PTR_ERR_OR_ZERO(clk_opp_table); + if (err) { + dev_err(emc->dev, "failed to set OPP clk: %d\n", err); + return err; + } + + hw_opp_table = dev_pm_opp_set_supported_hw(emc->dev, &hw_version, 1); + err = PTR_ERR_OR_ZERO(hw_opp_table); + if (err) { + dev_err(emc->dev, "failed to set OPP supported HW: %d\n", err); + goto put_clk_table; + } + + err = dev_pm_opp_of_add_table(emc->dev); + if (err) { + /* + * -ENODEV means that this is an older device-tree which + * doesn't have OPP table and EMC driver isn't very useful + * in this case. + */ + if (err == -ENODEV) + dev_err(emc->dev, "OPP table not found, please update your device tree\n"); + else + dev_err(emc->dev, "failed to add OPP table: %d\n", err); + + goto put_hw_table; + } + + dev_info(emc->dev, "OPP HW ver. 0x%x, current clock rate %lu MHz\n", + hw_version, clk_get_rate(emc->clk) / 1000000); + + /* first dummy rate-set initializes voltage state */ + err = dev_pm_opp_set_rate(emc->dev, clk_get_rate(emc->clk)); + if (err) { + dev_err(emc->dev, "failed to initialize OPP clock: %d\n", err); + goto remove_table; + } + + return 0; + +remove_table: + dev_pm_opp_of_remove_table(emc->dev); +put_hw_table: + dev_pm_opp_put_supported_hw(hw_opp_table); +put_clk_table: + dev_pm_opp_put_clkname(clk_opp_table); + + return err; +} + +static void devm_tegra_emc_unset_callback(void *data) +{ + tegra124_clk_set_emc_callbacks(NULL, NULL); +} + static int tegra_emc_probe(struct platform_device *pdev) { struct device_node *np; @@ -1188,6 +1469,7 @@ static int tegra_emc_probe(struct platform_device *pdev) if (!emc) return -ENOMEM;
+ mutex_init(&emc->rate_lock); emc->dev = &pdev->dev;
emc->regs = devm_platform_ioremap_resource(pdev, 0); @@ -1223,9 +1505,29 @@ static int tegra_emc_probe(struct platform_device *pdev) tegra124_clk_set_emc_callbacks(tegra_emc_prepare_timing_change, tegra_emc_complete_timing_change);
+ err = devm_add_action_or_reset(&pdev->dev, devm_tegra_emc_unset_callback, + NULL); + if (err) + return err; + + emc->clk = devm_clk_get(&pdev->dev, "emc"); + if (IS_ERR(emc->clk)) { + err = PTR_ERR(emc->clk); + dev_err(&pdev->dev, "failed to get EMC clock: %d\n", err); + return err; + } + + err = tegra_emc_opp_table_init(emc); + if (err) + return err; + + tegra_emc_rate_requests_init(emc); + 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 +1544,7 @@ 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..459211f50c08 100644 --- a/drivers/memory/tegra/tegra124.c +++ b/drivers/memory/tegra/tegra124.c @@ -4,7 +4,8 @@ */
#include <linux/of.h> -#include <linux/mm.h> +#include <linux/of_device.h> +#include <linux/slab.h>
#include <dt-bindings/memory/tegra124-mc.h>
@@ -1010,6 +1011,83 @@ 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 be high bandwidth pressure during initial filling + * 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 struct icc_node_data * +tegra124_mc_of_icc_xlate_extended(struct of_phandle_args *spec, void *data) +{ + struct tegra_mc *mc = icc_provider_to_tegra_mc(data); + const struct tegra_mc_client *client; + unsigned int i, idx = spec->args[0]; + struct icc_node_data *ndata; + struct icc_node *node; + + list_for_each_entry(node, &mc->provider.nodes, node_list) { + if (node->id != idx) + continue; + + ndata = kzalloc(sizeof(*ndata), GFP_KERNEL); + if (!ndata) + return ERR_PTR(-ENOMEM); + + client = &mc->soc->clients[idx]; + ndata->node = node; + + switch (client->swgroup) { + case TEGRA_SWGROUP_DC: + case TEGRA_SWGROUP_DCB: + case TEGRA_SWGROUP_PTC: + case TEGRA_SWGROUP_VI: + /* these clients are isochronous by default */ + ndata->tag = TEGRA_MC_ICC_TAG_ISO; + break; + + default: + ndata->tag = TEGRA_MC_ICC_TAG_DEFAULT; + break; + } + + return ndata; + } + + for (i = 0; i < mc->soc->num_clients; i++) { + if (mc->soc->clients[i].id == idx) + return ERR_PTR(-EPROBE_DEFER); + } + + dev_err(mc->dev, "invalid ICC client ID %u\n", idx); + + return ERR_PTR(-EINVAL); +} + +static const struct tegra_mc_icc_ops tegra124_mc_icc_ops = { + .xlate_extended = tegra124_mc_of_icc_xlate_extended, + .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 +1139,7 @@ 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 +1170,6 @@ 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 */