memory: tegra124: Support interconnect framework

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>
Acked-by: Georgi Djakov <georgi.djakov@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201228154920.18846-4-digetx@gmail.comSigned-off-by: Krzysztof Kozlowski <krzk@kernel.org>

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.

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 */