[PATCH v4 5/5] memory: tegra194: Support icc scaling

Aaron Kling via B4 Relay
2025-10-27T18:55:16Z

From: Aaron Kling <webgeek1234@gmail.com>

Add Interconnect framework support to dynamically set the DRAM
bandwidth from different clients. The MC driver is added as an ICC
provider and the EMC driver is already a provider.

Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
---
drivers/memory/tegra/tegra194.c | 59 ++++++++++++++++++++++++++++++++++++++++-
1 file changed, 58 insertions(+), 1 deletion(-)

diff --git a/drivers/memory/tegra/tegra194.c b/drivers/memory/tegra/tegra194.c
index 26035ac3a1eb51a3d8ce3830427b4412b48baf3c..e478587586e7f01afd41ff74d26a9a3f1d881347 100644
--- a/drivers/memory/tegra/tegra194.c
+++ b/drivers/memory/tegra/tegra194.c
@@ -1340,9 +1340,66 @@ static const struct tegra_mc_client tegra194_mc_clients[] = {
.security = 0x7fc,
},
},
+ }, {
+ .id = TEGRA_ICC_MC_CPU_CLUSTER0,
+ .name = "sw_cluster0",
+ .type = TEGRA_ICC_NISO,
+ }, {
+ .id = TEGRA_ICC_MC_CPU_CLUSTER1,
+ .name = "sw_cluster1",
+ .type = TEGRA_ICC_NISO,
+ }, {
+ .id = TEGRA_ICC_MC_CPU_CLUSTER2,
+ .name = "sw_cluster2",
+ .type = TEGRA_ICC_NISO,
+ }, {
+ .id = TEGRA_ICC_MC_CPU_CLUSTER3,
+ .name = "sw_cluster3",
+ .type = TEGRA_ICC_NISO,
},
};

+static int tegra194_mc_icc_set(struct icc_node *src, struct icc_node *dst)
+{
+ /* TODO: program PTSA */
+ return 0;
+}
+
+static int tegra194_mc_icc_aggregate(struct icc_node *node, u32 tag, u32 avg_bw,
+ u32 peak_bw, u32 *agg_avg, u32 *agg_peak)
+{
+ struct icc_provider *p = node->provider;
+ struct tegra_mc *mc = icc_provider_to_tegra_mc(p);
+
+ if (node->id == TEGRA_ICC_MC_CPU_CLUSTER0 ||
+ node->id == TEGRA_ICC_MC_CPU_CLUSTER1 ||
+ node->id == TEGRA_ICC_MC_CPU_CLUSTER2 ||
+ node->id == TEGRA_ICC_MC_CPU_CLUSTER3) {
+ if (mc)
+ peak_bw = peak_bw * mc->num_channels;
+ }
+
+ *agg_avg += avg_bw;
+ *agg_peak = max(*agg_peak, peak_bw);
+
+ return 0;
+}
+
+static int tegra194_mc_icc_get_init_bw(struct icc_node *node, u32 *avg, u32 *peak)
+{
+ *avg = 0;
+ *peak = 0;
+
+ return 0;
+}
+
+static const struct tegra_mc_icc_ops tegra194_mc_icc_ops = {
+ .xlate = tegra_mc_icc_xlate,
+ .aggregate = tegra194_mc_icc_aggregate,
+ .get_bw = tegra194_mc_icc_get_init_bw,
+ .set = tegra194_mc_icc_set,
+};
+
const struct tegra_mc_soc tegra194_mc_soc = {
.num_clients = ARRAY_SIZE(tegra194_mc_clients),
.clients = tegra194_mc_clients,
@@ -1355,7 +1412,7 @@ const struct tegra_mc_soc tegra194_mc_soc = {
MC_INT_SECURITY_VIOLATION | MC_INT_DECERR_EMEM,
.has_addr_hi_reg = true,
.ops = &tegra186_mc_ops,
- .icc_ops = &tegra_mc_icc_ops,
+ .icc_ops = &tegra194_mc_icc_ops,
.ch_intmask = 0x00000f00,
.global_intstatus_channel_shift = 8,
};

--
2.51.0