[Patch v2 2/9] memory: tegra: add interconnect support for DRAM scaling in Tegra234

From: Sumit Gupta
Date: Mon Feb 20 2023 - 09:07:16 EST


Add Interconnect framework support to dynamically set the DRAM
bandwidth from different clients. Both the MC and EMC drivers are
added as ICC providers. The path for any request is:
MC-Client[1-n] -> MC -> EMC -> EMEM/DRAM

MC client's request for bandwidth will go to the MC driver which
passes the client request info like BPMP Client ID, Client type
and the Bandwidth to the BPMP-FW. The final DRAM freq to achieve
the requested bandwidth is set by the BPMP-FW based on the passed
parameters.

Signed-off-by: Sumit Gupta <sumitg@xxxxxxxxxx>
---
drivers/memory/tegra/mc.c | 5 +
drivers/memory/tegra/tegra186-emc.c | 117 +++++++++++++++++++++++
drivers/memory/tegra/tegra234.c | 139 +++++++++++++++++++++++++++-
include/linux/tegra-icc.h | 65 +++++++++++++
include/soc/tegra/mc.h | 5 +
5 files changed, 330 insertions(+), 1 deletion(-)
create mode 100644 include/linux/tegra-icc.h

diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c
index 592907546ee6..7318eaa3819c 100644
--- a/drivers/memory/tegra/mc.c
+++ b/drivers/memory/tegra/mc.c
@@ -15,6 +15,7 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/sort.h>
+#include <linux/tegra-icc.h>

#include <soc/tegra/fuse.h>

@@ -792,6 +793,8 @@ static int tegra_mc_interconnect_setup(struct tegra_mc *mc)
mc->provider.data = &mc->provider;
mc->provider.set = mc->soc->icc_ops->set;
mc->provider.aggregate = mc->soc->icc_ops->aggregate;
+ mc->provider.get_bw = mc->soc->icc_ops->get_bw;
+ mc->provider.xlate = mc->soc->icc_ops->xlate;
mc->provider.xlate_extended = mc->soc->icc_ops->xlate_extended;

err = icc_provider_add(&mc->provider);
@@ -828,6 +831,8 @@ static int tegra_mc_interconnect_setup(struct tegra_mc *mc)
err = icc_link_create(node, TEGRA_ICC_MC);
if (err)
goto remove_nodes;
+
+ node->data = (char *)&(mc->soc->clients[i]);
}

return 0;
diff --git a/drivers/memory/tegra/tegra186-emc.c b/drivers/memory/tegra/tegra186-emc.c
index 26e763bde92a..756a5fefb383 100644
--- a/drivers/memory/tegra/tegra186-emc.c
+++ b/drivers/memory/tegra/tegra186-emc.c
@@ -7,9 +7,11 @@
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
+#include <linux/of_platform.h>
#include <linux/platform_device.h>

#include <soc/tegra/bpmp.h>
+#include "mc.h"

struct tegra186_emc_dvfs {
unsigned long latency;
@@ -29,8 +31,15 @@ struct tegra186_emc {
unsigned long min_rate;
unsigned long max_rate;
} debugfs;
+
+ struct icc_provider provider;
};

+static inline struct tegra186_emc *to_tegra186_emc(struct icc_provider *provider)
+{
+ return container_of(provider, struct tegra186_emc, provider);
+}
+
/*
* debugfs interface
*
@@ -146,11 +155,104 @@ DEFINE_DEBUGFS_ATTRIBUTE(tegra186_emc_debug_max_rate_fops,
tegra186_emc_debug_max_rate_get,
tegra186_emc_debug_max_rate_set, "%llu\n");

+/*
+ * tegra_emc_icc_set_bw() - Set BW api for EMC provider
+ * @src: ICC node for External Memory Controller (EMC)
+ * @dst: ICC node for External Memory (DRAM)
+ *
+ * Do nothing here as info to BPMP-FW is now passed in the BW set function
+ * of the MC driver. BPMP-FW sets the final Freq based on the passed values.
+ */
+static int tegra_emc_icc_set_bw(struct icc_node *src, struct icc_node *dst)
+{
+ return 0;
+}
+
+static struct icc_node *
+tegra_emc_of_icc_xlate(struct of_phandle_args *spec, void *data)
+{
+ struct icc_provider *provider = data;
+ 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;
+
+ return node;
+ }
+
+ return ERR_PTR(-EPROBE_DEFER);
+}
+
+static int tegra_emc_icc_get_init_bw(struct icc_node *node, u32 *avg, u32 *peak)
+{
+ *avg = 0;
+ *peak = 0;
+
+ return 0;
+}
+
+static int tegra_emc_interconnect_init(struct tegra186_emc *emc)
+{
+ struct tegra_mc *mc = dev_get_drvdata(emc->dev->parent);
+ const struct tegra_mc_soc *soc = mc->soc;
+ struct icc_node *node;
+ int err;
+
+ emc->provider.dev = emc->dev;
+ emc->provider.set = tegra_emc_icc_set_bw;
+ emc->provider.data = &emc->provider;
+ emc->provider.aggregate = soc->icc_ops->aggregate;
+ emc->provider.xlate = tegra_emc_of_icc_xlate;
+ emc->provider.get_bw = tegra_emc_icc_get_init_bw;
+
+ 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 tegra186_emc_probe(struct platform_device *pdev)
{
struct mrq_emc_dvfs_latency_response response;
struct tegra_bpmp_message msg;
struct tegra186_emc *emc;
+ struct tegra_mc *mc;
unsigned int i;
int err;

@@ -158,6 +260,9 @@ static int tegra186_emc_probe(struct platform_device *pdev)
if (!emc)
return -ENOMEM;

+ platform_set_drvdata(pdev, emc);
+ emc->dev = &pdev->dev;
+
emc->bpmp = tegra_bpmp_get(&pdev->dev);
if (IS_ERR(emc->bpmp))
return dev_err_probe(&pdev->dev, PTR_ERR(emc->bpmp), "failed to get BPMP\n");
@@ -236,6 +341,17 @@ static int tegra186_emc_probe(struct platform_device *pdev)
debugfs_create_file("max_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra186_emc_debug_max_rate_fops);

+ mc = dev_get_drvdata(emc->dev->parent);
+ if (mc && mc->soc->icc_ops) {
+ if (tegra_bpmp_mrq_is_supported(emc->bpmp, MRQ_BWMGR_INT)) {
+ err = tegra_emc_interconnect_init(emc);
+ if (err)
+ goto put_bpmp;
+ } else {
+ dev_info(&pdev->dev, "MRQ_BWMGR_INT not present\n");
+ }
+ }
+
return 0;

put_bpmp:
@@ -272,6 +388,7 @@ static struct platform_driver tegra186_emc_driver = {
.name = "tegra186-emc",
.of_match_table = tegra186_emc_of_match,
.suppress_bind_attrs = true,
+ .sync_state = icc_sync_state,
},
.probe = tegra186_emc_probe,
.remove = tegra186_emc_remove,
diff --git a/drivers/memory/tegra/tegra234.c b/drivers/memory/tegra/tegra234.c
index 02dcc5748bba..b40229926558 100644
--- a/drivers/memory/tegra/tegra234.c
+++ b/drivers/memory/tegra/tegra234.c
@@ -1,18 +1,24 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * Copyright (C) 2021-2022, NVIDIA CORPORATION. All rights reserved.
+ * Copyright (C) 20212-2023, NVIDIA CORPORATION. All rights reserved.
*/

#include <soc/tegra/mc.h>

#include <dt-bindings/memory/tegra234-mc.h>
+#include <linux/interconnect.h>
+#include <linux/of_device.h>
+#include <linux/tegra-icc.h>

+#include <soc/tegra/bpmp.h>
#include "mc.h"

static const struct tegra_mc_client tegra234_mc_clients[] = {
{
.id = TEGRA234_MEMORY_CLIENT_MGBEARD,
.name = "mgbeard",
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_MGBE,
.regs = {
.sid = {
@@ -23,6 +29,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_MGBEBRD,
.name = "mgbebrd",
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_MGBE_VF1,
.regs = {
.sid = {
@@ -33,6 +41,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_MGBECRD,
.name = "mgbecrd",
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_MGBE_VF2,
.regs = {
.sid = {
@@ -43,6 +53,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_MGBEDRD,
.name = "mgbedrd",
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_MGBE_VF3,
.regs = {
.sid = {
@@ -52,6 +64,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
},
}, {
.id = TEGRA234_MEMORY_CLIENT_MGBEAWR,
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.name = "mgbeawr",
.sid = TEGRA234_SID_MGBE,
.regs = {
@@ -63,6 +77,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_MGBEBWR,
.name = "mgbebwr",
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_MGBE_VF1,
.regs = {
.sid = {
@@ -73,6 +89,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_MGBECWR,
.name = "mgbecwr",
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_MGBE_VF2,
.regs = {
.sid = {
@@ -83,6 +101,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_SDMMCRAB,
.name = "sdmmcrab",
+ .bpmp_id = TEGRA_ICC_BPMP_SDMMC_4,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_SDMMC4,
.regs = {
.sid = {
@@ -93,6 +113,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_MGBEDWR,
.name = "mgbedwr",
+ .bpmp_id = TEGRA_ICC_BPMP_EQOS,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_MGBE_VF3,
.regs = {
.sid = {
@@ -103,6 +125,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_SDMMCWAB,
.name = "sdmmcwab",
+ .bpmp_id = TEGRA_ICC_BPMP_SDMMC_4,
+ .type = TEGRA_ICC_NISO,
.sid = TEGRA234_SID_SDMMC4,
.regs = {
.sid = {
@@ -153,6 +177,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_APEDMAR,
.name = "apedmar",
+ .bpmp_id = TEGRA_ICC_BPMP_APEDMA,
+ .type = TEGRA_ICC_ISO_AUDIO,
.sid = TEGRA234_SID_APE,
.regs = {
.sid = {
@@ -163,6 +189,8 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
}, {
.id = TEGRA234_MEMORY_CLIENT_APEDMAW,
.name = "apedmaw",
+ .bpmp_id = TEGRA_ICC_BPMP_APEDMA,
+ .type = TEGRA_ICC_ISO_AUDIO,
.sid = TEGRA234_SID_APE,
.regs = {
.sid = {
@@ -333,6 +361,114 @@ static const struct tegra_mc_client tegra234_mc_clients[] = {
},
};

+/*
+ * tegra234_mc_icc_set() - Pass MC client info to the BPMP-FW
+ * @src: ICC node for Memory Controller's (MC) Client
+ * @dst: ICC node for Memory Controller (MC)
+ *
+ * Passing the current request info from the MC to the BPMP-FW where
+ * LA and PTSA registers are accessed and the final EMC freq is set
+ * based on client_id, type, latency and bandwidth.
+ * icc_set_bw() makes set_bw calls for both MC and EMC providers in
+ * sequence. Both the calls are protected by 'mutex_lock(&icc_lock)'.
+ * So, the data passed won't be updated by concurrent set calls from
+ * other clients.
+ */
+static int tegra234_mc_icc_set(struct icc_node *src, struct icc_node *dst)
+{
+ struct tegra_mc *mc = icc_provider_to_tegra_mc(dst->provider);
+ struct mrq_bwmgr_int_request bwmgr_req = { 0 };
+ struct mrq_bwmgr_int_response bwmgr_resp = { 0 };
+ const struct tegra_mc_client *pclient = src->data;
+ struct tegra_bpmp_message msg;
+ struct tegra_bpmp *bpmp;
+ int ret;
+
+ /*
+ * Same Src and Dst node will happen during boot from icc_node_add().
+ * This can be used to pre-initialize and set bandwidth for all clients
+ * before their drivers are loaded. We are skipping this case as for us,
+ * the pre-initialization already happened in Bootloader(MB2) and BPMP-FW.
+ */
+ if (src->id == dst->id)
+ return 0;
+
+ bpmp = of_tegra_bpmp_get();
+ if (IS_ERR(bpmp)) {
+ ret = PTR_ERR(bpmp);
+ return ret;
+ }
+
+ if (pclient->type == TEGRA_ICC_NISO)
+ bwmgr_req.bwmgr_calc_set_req.niso_bw = src->avg_bw;
+ else
+ bwmgr_req.bwmgr_calc_set_req.iso_bw = src->avg_bw;
+
+ bwmgr_req.bwmgr_calc_set_req.client_id = pclient->bpmp_id;
+
+ bwmgr_req.cmd = CMD_BWMGR_INT_CALC_AND_SET;
+ bwmgr_req.bwmgr_calc_set_req.mc_floor = src->peak_bw;
+ bwmgr_req.bwmgr_calc_set_req.floor_unit = BWMGR_INT_UNIT_KBPS;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.mrq = MRQ_BWMGR_INT;
+ msg.tx.data = &bwmgr_req;
+ msg.tx.size = sizeof(bwmgr_req);
+ msg.rx.data = &bwmgr_resp;
+ msg.rx.size = sizeof(bwmgr_resp);
+
+ ret = tegra_bpmp_transfer(bpmp, &msg);
+ if (ret < 0) {
+ dev_err(mc->dev, "BPMP transfer failed: %d\n", ret);
+ goto error;
+ }
+ if (msg.rx.ret < 0) {
+ pr_err("failed to set bandwidth for %u: %d\n",
+ bwmgr_req.bwmgr_calc_set_req.client_id, msg.rx.ret);
+ ret = -EINVAL;
+ }
+
+error:
+ tegra_bpmp_put(bpmp);
+ return ret;
+}
+
+static struct icc_node*
+tegra234_mc_of_icc_xlate(struct of_phandle_args *spec, void *data)
+{
+ struct tegra_mc *mc = icc_provider_to_tegra_mc(data);
+ unsigned int cl_id = spec->args[0];
+ struct icc_node *node;
+
+ list_for_each_entry(node, &mc->provider.nodes, node_list) {
+ if (node->id != cl_id)
+ continue;
+
+ return node;
+ }
+
+ /*
+ * If a client driver calls devm_of_icc_get() before the MC driver
+ * is probed, then return EPROBE_DEFER to the client driver.
+ */
+ return ERR_PTR(-EPROBE_DEFER);
+}
+
+static int tegra234_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 tegra234_mc_icc_ops = {
+ .xlate = tegra234_mc_of_icc_xlate,
+ .aggregate = icc_std_aggregate,
+ .get_bw = tegra234_mc_icc_get_init_bw,
+ .set = tegra234_mc_icc_set,
+};
+
const struct tegra_mc_soc tegra234_mc_soc = {
.num_clients = ARRAY_SIZE(tegra234_mc_clients),
.clients = tegra234_mc_clients,
@@ -345,6 +481,7 @@ const struct tegra_mc_soc tegra234_mc_soc = {
MC_INT_SECURITY_VIOLATION | MC_INT_DECERR_EMEM,
.has_addr_hi_reg = true,
.ops = &tegra186_mc_ops,
+ .icc_ops = &tegra234_mc_icc_ops,
.ch_intmask = 0x0000ff00,
.global_intstatus_channel_shift = 8,
/*
diff --git a/include/linux/tegra-icc.h b/include/linux/tegra-icc.h
new file mode 100644
index 000000000000..4b4d4bee290c
--- /dev/null
+++ b/include/linux/tegra-icc.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022-2023 NVIDIA CORPORATION. All rights reserved.
+ */
+
+#ifndef LINUX_TEGRA_ICC_H
+#define LINUX_TEGRA_ICC_H
+
+enum tegra_icc_client_type {
+ TEGRA_ICC_NONE,
+ TEGRA_ICC_NISO,
+ TEGRA_ICC_ISO_DISPLAY,
+ TEGRA_ICC_ISO_VI,
+ TEGRA_ICC_ISO_AUDIO,
+ TEGRA_ICC_ISO_VIFAL,
+};
+
+/* ICC ID's for MC client's used in BPMP */
+#define TEGRA_ICC_BPMP_DEBUG 1
+#define TEGRA_ICC_BPMP_CPU_CLUSTER0 2
+#define TEGRA_ICC_BPMP_CPU_CLUSTER1 3
+#define TEGRA_ICC_BPMP_CPU_CLUSTER2 4
+#define TEGRA_ICC_BPMP_GPU 5
+#define TEGRA_ICC_BPMP_CACTMON 6
+#define TEGRA_ICC_BPMP_DISPLAY 7
+#define TEGRA_ICC_BPMP_VI 8
+#define TEGRA_ICC_BPMP_EQOS 9
+#define TEGRA_ICC_BPMP_PCIE_0 10
+#define TEGRA_ICC_BPMP_PCIE_1 11
+#define TEGRA_ICC_BPMP_PCIE_2 12
+#define TEGRA_ICC_BPMP_PCIE_3 13
+#define TEGRA_ICC_BPMP_PCIE_4 14
+#define TEGRA_ICC_BPMP_PCIE_5 15
+#define TEGRA_ICC_BPMP_PCIE_6 16
+#define TEGRA_ICC_BPMP_PCIE_7 17
+#define TEGRA_ICC_BPMP_PCIE_8 18
+#define TEGRA_ICC_BPMP_PCIE_9 19
+#define TEGRA_ICC_BPMP_PCIE_10 20
+#define TEGRA_ICC_BPMP_DLA_0 21
+#define TEGRA_ICC_BPMP_DLA_1 22
+#define TEGRA_ICC_BPMP_SDMMC_1 23
+#define TEGRA_ICC_BPMP_SDMMC_2 24
+#define TEGRA_ICC_BPMP_SDMMC_3 25
+#define TEGRA_ICC_BPMP_SDMMC_4 26
+#define TEGRA_ICC_BPMP_NVDEC 27
+#define TEGRA_ICC_BPMP_NVENC 28
+#define TEGRA_ICC_BPMP_NVJPG_0 29
+#define TEGRA_ICC_BPMP_NVJPG_1 30
+#define TEGRA_ICC_BPMP_OFAA 31
+#define TEGRA_ICC_BPMP_XUSB_HOST 32
+#define TEGRA_ICC_BPMP_XUSB_DEV 33
+#define TEGRA_ICC_BPMP_TSEC 34
+#define TEGRA_ICC_BPMP_VIC 35
+#define TEGRA_ICC_BPMP_APE 36
+#define TEGRA_ICC_BPMP_APEDMA 37
+#define TEGRA_ICC_BPMP_SE 38
+#define TEGRA_ICC_BPMP_ISP 39
+#define TEGRA_ICC_BPMP_HDA 40
+#define TEGRA_ICC_BPMP_VIFAL 41
+#define TEGRA_ICC_BPMP_VI2FAL 42
+#define TEGRA_ICC_BPMP_VI2 43
+#define TEGRA_ICC_BPMP_RCE 44
+#define TEGRA_ICC_BPMP_PVA 45
+
+#endif /* LINUX_TEGRA_ICC_H */
diff --git a/include/soc/tegra/mc.h b/include/soc/tegra/mc.h
index 51a2263e1bc5..fefac9622987 100644
--- a/include/soc/tegra/mc.h
+++ b/include/soc/tegra/mc.h
@@ -13,6 +13,7 @@
#include <linux/irq.h>
#include <linux/reset-controller.h>
#include <linux/types.h>
+#include <linux/tegra-icc.h>

struct clk;
struct device;
@@ -26,6 +27,8 @@ struct tegra_mc_timing {

struct tegra_mc_client {
unsigned int id;
+ unsigned int bpmp_id;
+ enum tegra_icc_client_type type;
const char *name;
/*
* For Tegra210 and earlier, this is the SWGROUP ID used for IOVA translations in the
@@ -166,8 +169,10 @@ struct tegra_mc_icc_ops {
int (*set)(struct icc_node *src, struct icc_node *dst);
int (*aggregate)(struct icc_node *node, u32 tag, u32 avg_bw,
u32 peak_bw, u32 *agg_avg, u32 *agg_peak);
+ struct icc_node* (*xlate)(struct of_phandle_args *spec, void *data);
struct icc_node_data *(*xlate_extended)(struct of_phandle_args *spec,
void *data);
+ int (*get_bw)(struct icc_node *node, u32 *avg, u32 *peak);
};

struct tegra_mc_ops {
--
2.17.1