From: Thierry Reding <treding@xxxxxxxxxx>
This driver uses the services provided by the BPMP firmware driver to
implement a clock driver based on the MRQ_CLK request. This part of the
BPMP ABI provides a means to enumerate and control clocks and should
allow the driver to work on any chip that supports this ABI.
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
Changes in v2:
- rename ->prepare() and ->unprepare() implementations for consistency
- implement ->is_prepared() instead of ->is_enabled() to avoid the need
for atomic operations
- rename tegra_bpmp_clk_message.clk member to id
- remove a double semi-colon and a stray ampersand
- drop extra check for validity of parent index, the core does it
already
- make struct tegra_bpmp carry an array of struct tegra_bpmp_clk instead
of struct clk_hw to simplify some driver code
- zero out struct clk_init_data to avoid potentially uninitialized data
- use devm_clk_hw_register() instead of clk_register() because we never
need the opaque struct clk cookie
- rearrange functions so that they appear in the order specified by
struct clk_ops
drivers/clk/tegra/Kconfig | 4 +
drivers/clk/tegra/Makefile | 1 +
drivers/clk/tegra/clk-bpmp.c | 620 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 625 insertions(+)
create mode 100644 drivers/clk/tegra/clk-bpmp.c
diff --git a/drivers/clk/tegra/Kconfig b/drivers/clk/tegra/Kconfig
index 1ba30d1e14f2..7ddacae5d0b1 100644
--- a/drivers/clk/tegra/Kconfig
+++ b/drivers/clk/tegra/Kconfig
@@ -1,3 +1,7 @@
config TEGRA_CLK_EMC
def_bool y
depends on TEGRA124_EMC
+
+config CLK_TEGRA_BPMP
+ def_bool y
+ depends on TEGRA_BPMP
diff --git a/drivers/clk/tegra/Makefile b/drivers/clk/tegra/Makefile
index 33fd0938d79e..4be8af28ee61 100644
--- a/drivers/clk/tegra/Makefile
+++ b/drivers/clk/tegra/Makefile
@@ -22,3 +22,4 @@ obj-$(CONFIG_ARCH_TEGRA_124_SOC) += clk-tegra124-dfll-fcpu.o
obj-$(CONFIG_ARCH_TEGRA_132_SOC) += clk-tegra124.o
obj-y += cvb.o
obj-$(CONFIG_ARCH_TEGRA_210_SOC) += clk-tegra210.o
+obj-$(CONFIG_CLK_TEGRA_BPMP) += clk-bpmp.o
diff --git a/drivers/clk/tegra/clk-bpmp.c b/drivers/clk/tegra/clk-bpmp.c
new file mode 100644
index 000000000000..638ace64033b
--- /dev/null
+++ b/drivers/clk/tegra/clk-bpmp.c
@@ -0,0 +1,620 @@
+/*
+ * Copyright (C) 2016 NVIDIA Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/seq_buf.h>
+#include <linux/slab.h>
+
+#include <soc/tegra/bpmp.h>
+#include <soc/tegra/bpmp-abi.h>
+
+#define TEGRA_BPMP_DUMP_CLOCK_INFO 0
+
+#define TEGRA_BPMP_CLK_HAS_MUX BIT(0)
+#define TEGRA_BPMP_CLK_HAS_SET_RATE BIT(1)
+#define TEGRA_BPMP_CLK_IS_ROOT BIT(2)
+
+struct tegra_bpmp_clk_info {
+ unsigned int id;
+ char name[MRQ_CLK_NAME_MAXLEN];
+ unsigned int parents[MRQ_CLK_MAX_PARENTS];
+ unsigned int num_parents;
+ unsigned long flags;
+};
+
+struct tegra_bpmp_clk {
+ struct clk_hw hw;
+
+ struct tegra_bpmp *bpmp;
+ unsigned int id;
+
+ unsigned int num_parents;
+ unsigned int *parents;
+};
+
+static inline struct tegra_bpmp_clk *to_tegra_bpmp_clk(struct clk_hw *hw)
+{
+ return container_of(hw, struct tegra_bpmp_clk, hw);
+}
+
+struct tegra_bpmp_clk_message {
+ unsigned int cmd;
+ unsigned int id;
+
+ struct {
+ const void *data;
+ size_t size;
+ } tx;
+
+ struct {
+ void *data;
+ size_t size;
+ } rx;
+};
+
+static int tegra_bpmp_clk_transfer(struct tegra_bpmp *bpmp,
+ const struct tegra_bpmp_clk_message *clk)
+{
+ struct mrq_clk_request request;
+ struct tegra_bpmp_message msg;
+ void *req = &request;
+
+ memset(&request, 0, sizeof(request));
+ request.cmd_and_id = (clk->cmd << 24) | clk->id;
+
+ /*
+ * The mrq_clk_request structure has an anonymous union at offset 4
+ * that contains all possible sub-command structures. Copy the data
+ * to that union. Ideally we'd be able to refer to it by name, but
+ * doing so would require changing the ABI header and increase the
+ * maintenance burden.
+ */
+ memcpy(req + 4, clk->tx.data, clk->tx.size);
+
+ memset(&msg, 0, sizeof(msg));
+ msg.mrq = MRQ_CLK;
+ msg.tx.data = &request;
+ msg.tx.size = sizeof(request);
+ msg.rx.data = clk->rx.data;
+ msg.rx.size = clk->rx.size;
+
+ return tegra_bpmp_transfer(bpmp, &msg);
+}
+
+static int tegra_bpmp_clk_prepare(struct clk_hw *hw)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct tegra_bpmp_clk_message msg;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_ENABLE;
+ msg.id = clk->id;
+
+ return tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+}
+
+static void tegra_bpmp_clk_unprepare(struct clk_hw *hw)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct tegra_bpmp_clk_message msg;
+ int err;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_DISABLE;
+ msg.id = clk->id;
+
+ err = tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+ if (err < 0)
+ dev_err(clk->bpmp->dev, "failed to disable clock %s: %d\n",
+ clk_hw_get_name(hw), err);
+}
+
+static int tegra_bpmp_clk_is_prepared(struct clk_hw *hw)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct cmd_clk_is_enabled_response response;
+ struct tegra_bpmp_clk_message msg;
+ int err;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_IS_ENABLED;
+ msg.id = clk->id;
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ err = tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+ if (err < 0)
+ return err;
+
+ return response.state;
+}
+
+static unsigned long tegra_bpmp_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct cmd_clk_get_rate_response response;
+ struct cmd_clk_get_rate_request request;
+ struct tegra_bpmp_clk_message msg;
+ int err;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_GET_RATE;
+ msg.id = clk->id;
+ msg.tx.data = &request;
+ msg.tx.size = sizeof(request);
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ err = tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+ if (err < 0)
+ return err;
+
+ return response.rate;
+}
+
+static long tegra_bpmp_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct cmd_clk_round_rate_response response;
+ struct cmd_clk_round_rate_request request;
+ struct tegra_bpmp_clk_message msg;
+ int err;
+
+ memset(&request, 0, sizeof(request));
+ request.rate = rate;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_ROUND_RATE;
+ msg.id = clk->id;
+ msg.tx.data = &request;
+ msg.tx.size = sizeof(request);
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ err = tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+ if (err < 0)
+ return err;
+
+ return response.rate;
+}
+
+static int tegra_bpmp_clk_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct cmd_clk_set_parent_response response;
+ struct cmd_clk_set_parent_request request;
+ struct tegra_bpmp_clk_message msg;
+ int err;
+
+ memset(&request, 0, sizeof(request));
+ request.parent_id = clk->parents[index];
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_SET_PARENT;
+ msg.id = clk->id;
+ msg.tx.data = &request;
+ msg.tx.size = sizeof(request);
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ err = tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+ if (err < 0)
+ return err;
+
+ /* XXX check parent ID in response */
+
+ return 0;
+}
+
+static u8 tegra_bpmp_clk_get_parent(struct clk_hw *hw)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct cmd_clk_get_parent_response response;
+ struct tegra_bpmp_clk_message msg;
+ unsigned int i;
+ int err;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_GET_PARENT;
+ msg.id = clk->id;
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ err = tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+ if (err < 0) {
+ dev_err(clk->bpmp->dev, "failed to get parent for %s: %d\n",
+ clk_hw_get_name(hw), err);
+ return U8_MAX;
+ }
+
+ for (i = 0; i < clk->num_parents; i++)
+ if (clk->parents[i] == response.parent_id)
+ return i;
+
+ return U8_MAX;
+}
+
+static int tegra_bpmp_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct tegra_bpmp_clk *clk = to_tegra_bpmp_clk(hw);
+ struct cmd_clk_set_rate_response response;
+ struct cmd_clk_set_rate_request request;
+ struct tegra_bpmp_clk_message msg;
+
+ memset(&request, 0, sizeof(request));
+ request.rate = rate;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_SET_RATE;
+ msg.id = clk->id;
+ msg.tx.data = &request;
+ msg.tx.size = sizeof(request);
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ return tegra_bpmp_clk_transfer(clk->bpmp, &msg);
+}
+
+static const struct clk_ops tegra_bpmp_clk_gate_ops = {
+ .prepare = tegra_bpmp_clk_prepare,
+ .unprepare = tegra_bpmp_clk_unprepare,
+ .is_prepared = tegra_bpmp_clk_is_prepared,
+ .recalc_rate = tegra_bpmp_clk_recalc_rate,
+};
+
+static const struct clk_ops tegra_bpmp_clk_mux_ops = {
+ .prepare = tegra_bpmp_clk_prepare,
+ .unprepare = tegra_bpmp_clk_unprepare,
+ .is_prepared = tegra_bpmp_clk_is_prepared,
+ .recalc_rate = tegra_bpmp_clk_recalc_rate,
+ .set_parent = tegra_bpmp_clk_set_parent,
+ .get_parent = tegra_bpmp_clk_get_parent,
+};
+
+static const struct clk_ops tegra_bpmp_clk_rate_ops = {
+ .prepare = tegra_bpmp_clk_prepare,
+ .unprepare = tegra_bpmp_clk_unprepare,
+ .is_prepared = tegra_bpmp_clk_is_prepared,
+ .recalc_rate = tegra_bpmp_clk_recalc_rate,
+ .round_rate = tegra_bpmp_clk_round_rate,
+ .set_rate = tegra_bpmp_clk_set_rate,
+};
+
+static const struct clk_ops tegra_bpmp_clk_mux_rate_ops = {
+ .prepare = tegra_bpmp_clk_prepare,
+ .unprepare = tegra_bpmp_clk_unprepare,
+ .is_prepared = tegra_bpmp_clk_is_prepared,
+ .recalc_rate = tegra_bpmp_clk_recalc_rate,
+ .round_rate = tegra_bpmp_clk_round_rate,
+ .set_parent = tegra_bpmp_clk_set_parent,
+ .get_parent = tegra_bpmp_clk_get_parent,
+ .set_rate = tegra_bpmp_clk_set_rate,
+};
+
+static int tegra_bpmp_clk_get_max_id(struct tegra_bpmp *bpmp)
+{
+ struct cmd_clk_get_max_clk_id_response response;
+ struct tegra_bpmp_clk_message msg;
+ int err;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_GET_MAX_CLK_ID;
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ err = tegra_bpmp_clk_transfer(bpmp, &msg);
+ if (err < 0)
+ return err;
+
+ if (response.max_id > INT_MAX)
+ return -E2BIG;
+
+ return response.max_id;
+}
+
+static int tegra_bpmp_clk_get_info(struct tegra_bpmp *bpmp, unsigned int id,
+ struct tegra_bpmp_clk_info *info)
+{
+ struct cmd_clk_get_all_info_response response;
+ struct tegra_bpmp_clk_message msg;
+ unsigned int i;
+ int err;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd = CMD_CLK_GET_ALL_INFO;
+ msg.id = id;
+ msg.rx.data = &response;
+ msg.rx.size = sizeof(response);
+
+ err = tegra_bpmp_clk_transfer(bpmp, &msg);
+ if (err < 0)
+ return err;
+
+ strlcpy(info->name, response.name, MRQ_CLK_NAME_MAXLEN);
+ info->num_parents = response.num_parents;
+
+ for (i = 0; i < info->num_parents; i++)
+ info->parents[i] = response.parents[i];
+
+ info->flags = response.flags;
+
+ return 0;
+}
+
+static void tegra_bpmp_clk_info_dump(struct tegra_bpmp *bpmp,
+ const char *level,
+ const struct tegra_bpmp_clk_info *info)
+{
+ const char *prefix = "";
+ struct seq_buf buf;
+ unsigned int i;
+ char flags[64];
+
+ seq_buf_init(&buf, flags, sizeof(flags));
+
+ if (info->flags)
+ seq_buf_printf(&buf, "(");
+
+ if (info->flags & TEGRA_BPMP_CLK_HAS_MUX) {
+ seq_buf_printf(&buf, "%smux", prefix);
+ prefix = ", ";
+ }
+
+ if ((info->flags & TEGRA_BPMP_CLK_HAS_SET_RATE) == 0) {
+ seq_buf_printf(&buf, "%sfixed", prefix);
+ prefix = ", ";
+ }
+
+ if (info->flags & TEGRA_BPMP_CLK_IS_ROOT) {
+ seq_buf_printf(&buf, "%sroot", prefix);
+ prefix = ", ";
+ }
+
+ if (info->flags)
+ seq_buf_printf(&buf, ")");
+
+ dev_printk(level, bpmp->dev, "%03u: %s\n", info->id, info->name);
+ dev_printk(level, bpmp->dev, " flags: %lx %s\n", info->flags, flags);
+ dev_printk(level, bpmp->dev, " parents: %u\n", info->num_parents);
+
+ for (i = 0; i < info->num_parents; i++)
+ dev_printk(level, bpmp->dev, " %03u\n", info->parents[i]);
+}
+
+static int tegra_bpmp_probe_clocks(struct tegra_bpmp *bpmp,
+ struct tegra_bpmp_clk_info **clocksp)
+{
+ struct tegra_bpmp_clk_info *clocks;
+ unsigned int max_id, id, count = 0;
+ unsigned int holes = 0;
+ int err;
+
+ err = tegra_bpmp_clk_get_max_id(bpmp);
+ if (err < 0)
+ return err;
+
+ max_id = err;
+
+ dev_dbg(bpmp->dev, "maximum clock ID: %u\n", max_id);
+
+ clocks = kcalloc(max_id + 1, sizeof(*clocks), GFP_KERNEL);
+ if (!clocks)
+ return -ENOMEM;
+
+ for (id = 0; id <= max_id; id++) {
+ struct tegra_bpmp_clk_info *info = &clocks[count];
+
+ err = tegra_bpmp_clk_get_info(bpmp, id, info);
+ if (err < 0) {
+ dev_err(bpmp->dev, "failed to query clock %u: %d\n",
+ id, err);
+ continue;
+ }
+
+ if (info->num_parents >= U8_MAX) {
+ dev_err(bpmp->dev,
+ "clock %u has too many parents (%u, max: %u)\n",
+ id, info->num_parents, U8_MAX);
+ continue;
+ }
+
+ /* clock not exposed by BPMP */
+ if (info->name[0] == '\0') {
+ holes++;
+ continue;
+ }
+
+ info->id = id;
+ count++;
+
+ if (TEGRA_BPMP_DUMP_CLOCK_INFO)
+ tegra_bpmp_clk_info_dump(bpmp, KERN_DEBUG, info);
+ }
+
+ dev_dbg(bpmp->dev, "holes: %u\n", holes);
+ *clocksp = clocks;
+
+ return count;
+}
+
+static const struct tegra_bpmp_clk_info *
+tegra_bpmp_clk_find(const struct tegra_bpmp_clk_info *clocks,
+ unsigned int num_clocks, unsigned int id)
+{
+ unsigned int i;
+
+ for (i = 0; i < num_clocks; i++)
+ if (clocks[i].id == id)
+ return &clocks[i];
+
+ return NULL;
+}
+
+static struct tegra_bpmp_clk *
+tegra_bpmp_clk_register(struct tegra_bpmp *bpmp,
+ const struct tegra_bpmp_clk_info *info,
+ const struct tegra_bpmp_clk_info *clocks,
+ unsigned int num_clocks)
+{
+ struct tegra_bpmp_clk *clk;
+ struct clk_init_data init;
+ const char **parents;
+ unsigned int i;
+ int err;
+
+ clk = devm_kzalloc(bpmp->dev, sizeof(*clk), GFP_KERNEL);
+ if (!clk)
+ return ERR_PTR(-ENOMEM);
+
+ clk->id = info->id;
+ clk->bpmp = bpmp;
+
+ clk->parents = devm_kcalloc(bpmp->dev, info->num_parents,
+ sizeof(*clk->parents), GFP_KERNEL);
+ if (!clk->parents)
+ return ERR_PTR(-ENOMEM);
+
+ clk->num_parents = info->num_parents;
+
+ /* hardware clock initialization */
+ memset(&init, 0, sizeof(init));
+ init.name = info->name;
+ clk->hw.init = &init;
+
+ if (info->flags & TEGRA_BPMP_CLK_HAS_MUX) {
+ if (info->flags & TEGRA_BPMP_CLK_HAS_SET_RATE)
+ init.ops = &tegra_bpmp_clk_mux_rate_ops;
+ else
+ init.ops = &tegra_bpmp_clk_mux_ops;
+ } else {
+ if (info->flags & TEGRA_BPMP_CLK_HAS_SET_RATE)
+ init.ops = &tegra_bpmp_clk_rate_ops;
+ else
+ init.ops = &tegra_bpmp_clk_gate_ops;
+ }
+
+ init.num_parents = info->num_parents;
+
+ parents = kcalloc(info->num_parents, sizeof(*parents), GFP_KERNEL);
+ if (!parents)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < info->num_parents; i++) {
+ const struct tegra_bpmp_clk_info *parent;
+
+ /* keep a private copy of the ID to parent index map */
+ clk->parents[i] = info->parents[i];
+
+ parent = tegra_bpmp_clk_find(clocks, num_clocks,
+ info->parents[i]);
+ if (!parent) {
+ dev_err(bpmp->dev, "no parent %u found for %u\n",
+ info->parents[i], info->id);
+ continue;
+ }
+
+ parents[i] = parent->name;
+ }
+
+ init.parent_names = parents;
+
+ err = devm_clk_hw_register(bpmp->dev, &clk->hw);
+
+ kfree(parents);
+
+ if (err < 0)
+ return ERR_PTR(err);
+
+ return clk;
+}
+
+static int tegra_bpmp_register_clocks(struct tegra_bpmp *bpmp,
+ struct tegra_bpmp_clk_info *infos,
+ unsigned int count)
+{
+ struct tegra_bpmp_clk *clk;
+ unsigned int i;
+
+ bpmp->num_clocks = count;
+
+ bpmp->clocks = devm_kcalloc(bpmp->dev, count, sizeof(clk), GFP_KERNEL);
+ if (!bpmp->clocks)
+ return -ENOMEM;
+
+ for (i = 0; i < count; i++) {
+ struct tegra_bpmp_clk_info *info = &infos[i];
+
+ clk = tegra_bpmp_clk_register(bpmp, info, infos, count);
+ if (IS_ERR(clk)) {
+ dev_err(bpmp->dev,
+ "failed to register clock %u (%s): %ld\n",
+ info->id, info->name, PTR_ERR(clk));
+ continue;
+ }
+
+ bpmp->clocks[i] = clk;
+ }
+
+ return 0;
+}
+
+static void tegra_bpmp_unregister_clocks(struct tegra_bpmp *bpmp)
+{
+ unsigned int i;
+
+ for (i = 0; i < bpmp->num_clocks; i++)
+ clk_hw_unregister(&bpmp->clocks[i]->hw);
+}
+
+static struct clk_hw *tegra_bpmp_clk_of_xlate(struct of_phandle_args *clkspec,
+ void *data)
+{
+ unsigned int id = clkspec->args[0], i;
+ struct tegra_bpmp *bpmp = data;
+
+ for (i = 0; i < bpmp->num_clocks; i++)
+ if (bpmp->clocks[i]->id == id)
+ return &bpmp->clocks[i]->hw;
+
+ return NULL;
+}
+
+int tegra_bpmp_init_clocks(struct tegra_bpmp *bpmp)
+{
+ struct tegra_bpmp_clk_info *clocks;
+ unsigned int count;
+ int err;
+
+ err = tegra_bpmp_probe_clocks(bpmp, &clocks);
+ if (err < 0)
+ return err;
+
+ count = err;
+
+ dev_dbg(bpmp->dev, "%u clocks probed\n", count);
+
+ err = tegra_bpmp_register_clocks(bpmp, clocks, count);
+ if (err < 0)
+ goto free;
+
+ err = of_clk_add_hw_provider(bpmp->dev->of_node,
+ tegra_bpmp_clk_of_xlate,
+ bpmp);
+ if (err < 0) {
+ tegra_bpmp_unregister_clocks(bpmp);
+ goto free;
+ }
+
+free:
+ kfree(clocks);
+ return err;
+}
--
2.10.2
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