Re: [PATCH v2 01/12] scmi: refactor the code to hide a channel from devices

Hi Etienne,

On Thu, Aug 03, 2023 at 09:24:51AM +0000, Etienne CARRIERE wrote:

Hello Takahiro-san,

Sorry again for this late feedback. Testing the series against stm32mp135f-dk board which is using SCMI resources, I see the board fails to boot.

...

From: AKASHI Takahiro takahiro.akashi@linaro.org To: trini@konsulko.com, sjg@chromium.org Cc: etienne.carriere@st.com, u-boot@lists.denx.de, AKASHI Takahiro takahiro.akashi@linaro.org Subject: [PATCH v2 01/12] scmi: refactor the code to hide a channel from devices Date: Wed, 26 Jul 2023 17:37:57 +0900 [thread overview] Message-ID: 20230726083808.140780-2-takahiro.akashi@linaro.org (raw) In-Reply-To: 20230726083808.140780-1-takahiro.akashi@linaro.org

The commit 85dc58289238 ("firmware: scmi: prepare uclass to pass channel reference") added an explicit parameter, channel, but it seems to make the code complex.

Hiding this parameter will allow for adding a generic (protocol-agnostic) helper function, i.e. for PROTOCOL_VERSION, in a later patch.

Signed-off-by: AKASHI Takahiro takahiro.akashi@linaro.org

---

v2

• new patch

---

drivers/clk/clk_scmi.c | 27 ++------- drivers/firmware/scmi/scmi_agent-uclass.c | 74 ++++++++++++++++++----- drivers/power/regulator/scmi_regulator.c | 27 +++------ drivers/reset/reset-scmi.c | 19 +----- include/scmi_agent.h | 15 +++-- 5 files changed, 86 insertions(+), 76 deletions(-)

diff --git a/drivers/clk/clk_scmi.c b/drivers/clk/clk_scmi.c index d172fed24c9d..34a49363a51a 100644 --- a/drivers/clk/clk_scmi.c +++ b/drivers/clk/clk_scmi.c @@ -13,17 +13,8 @@ #include <asm/types.h> #include <linux/clk-provider.h>

-/**

• • struct scmi_clk_priv - Private data for SCMI clocks
• • @channel: Reference to the SCMI channel to use
• */

-struct scmi_clk_priv {

• struct scmi_channel *channel;

-};

static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks) {

• struct scmi_clk_priv *priv = dev_get_priv(dev); struct scmi_clk_protocol_attr_out out; struct scmi_msg msg = { .protocol_id = SCMI_PROTOCOL_ID_CLOCK,

@@ -33,7 +24,7 @@ static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks) }; int ret;

• ret = devm_scmi_process_msg(dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(dev, &msg); if (ret) return ret;

@@ -44,7 +35,6 @@ static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)

static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name) {

• struct scmi_clk_priv *priv = dev_get_priv(dev); struct scmi_clk_attribute_in in = { .clock_id = clkid, };

@@ -59,7 +49,7 @@ static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name) }; int ret;

• ret = devm_scmi_process_msg(dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(dev, &msg); if (ret) return ret;

@@ -70,7 +60,6 @@ static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)

static int scmi_clk_gate(struct clk *clk, int enable) {

• struct scmi_clk_priv *priv = dev_get_priv(clk->dev); struct scmi_clk_state_in in = { .clock_id = clk->id, .attributes = enable,

@@ -81,7 +70,7 @@ static int scmi_clk_gate(struct clk *clk, int enable) in, out); int ret;

• ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(clk->dev, &msg); if (ret) return ret;

@@ -100,7 +89,6 @@ static int scmi_clk_disable(struct clk *clk)

static ulong scmi_clk_get_rate(struct clk *clk) {

• struct scmi_clk_priv *priv = dev_get_priv(clk->dev); struct scmi_clk_rate_get_in in = { .clock_id = clk->id, };

@@ -110,7 +98,7 @@ static ulong scmi_clk_get_rate(struct clk *clk) in, out); int ret;

• ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(clk->dev, &msg); if (ret < 0) return ret;

@@ -123,7 +111,6 @@ static ulong scmi_clk_get_rate(struct clk *clk)

static ulong scmi_clk_set_rate(struct clk *clk, ulong rate) {

• struct scmi_clk_priv *priv = dev_get_priv(clk->dev); struct scmi_clk_rate_set_in in = { .clock_id = clk->id, .flags = SCMI_CLK_RATE_ROUND_CLOSEST,

@@ -136,7 +123,7 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate) in, out); int ret;

• ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(clk->dev, &msg); if (ret < 0) return ret;

@@ -149,12 +136,11 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)

static int scmi_clk_probe(struct udevice *dev) {

• struct scmi_clk_priv *priv = dev_get_priv(dev); struct clk *clk; size_t num_clocks, i; int ret;

• ret = devm_scmi_of_get_channel(dev, &priv->channel);

• ret = devm_scmi_of_get_channel(dev); if (ret) return ret;

@@ -205,5 +191,4 @@ U_BOOT_DRIVER(scmi_clock) = { .id = UCLASS_CLK, .ops = &scmi_clk_ops, .probe = scmi_clk_probe,

• .priv_auto = sizeof(struct scmi_clk_priv *),

}; diff --git a/drivers/firmware/scmi/scmi_agent-uclass.c b/drivers/firmware/scmi/scmi_agent-uclass.c index 02de692d66f3..39cf15c88f75 100644 --- a/drivers/firmware/scmi/scmi_agent-uclass.c +++ b/drivers/firmware/scmi/scmi_agent-uclass.c @@ -8,6 +8,7 @@ #include <common.h> #include <dm.h> #include <errno.h> +#include <scmi_agent.h> #include <scmi_agent-uclass.h> #include <scmi_protocols.h> #include <dm/device_compat.h> @@ -129,43 +130,88 @@ static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev) return (const struct scmi_agent_ops *)dev->driver->ops; }

-int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel) +/**

• • scmi_of_get_channel() - Get SCMI channel handle
• • @dev: SCMI agent device
• • @channel: Output reference to the SCMI channel upon success
• • On return, @channel will be set.
• • Return 0 on success and a negative errno on failure
• */

+static int scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel) +{

• const struct scmi_agent_ops *ops;
• ops = transport_dev_ops(dev);
• if (ops->of_get_channel)

• return ops->of_get_channel(dev, channel);
  

• else

• return -EPROTONOSUPPORT;
  

+}

+int devm_scmi_of_get_channel(struct udevice *dev) { struct udevice *parent;

• struct scmi_agent_proto_priv *priv = dev_get_parent_priv(dev);

This parent lookup does not match when CONFIG_CLK_CCF is enabled. When so, the scmi clock device is on the clock itself but a child udevice of some udevice held by the common clock framework (CCF). Platforms from the stm32mp13 family do enable SCMI clock and CCF.

I tested my patch on sandbox, where CCF is also enabled, and "ut dm scmi_clocks" is passed without any error. So I'm not sure if the point you mentioned above is a root cause.

-Takahiro Akashi

It can propose a way to go, using find_scmi_transport_device() to provide the agent's 1st child private data as an output argument: //patch-start -static struct udevice *find_scmi_transport_device(struct udevice *dev) +static struct udevice * +find_scmi_transport_device(struct udevice *dev,

•                      struct scmi_agent_proto_priv **priv)
  

{ struct udevice *parent = dev;

•   struct scmi_agent_proto_priv *parent_priv;
  
    do {
  

•           parent_priv = dev_get_parent_priv(parent);
            parent = dev_get_parent(parent);
    } while (parent && device_get_uclass_id(parent) != UCLASS_SCMI_AGENT);
  
    if (!parent)
            dev_err(dev, "Invalid SCMI device, agent not found\n");
  

•   else if (priv)
  

•           *priv = parent_priv;
  
    return parent;
  

} //end patch

Tested OK on stm32mp13 with the remaining patch series applied (minor conflics).

BR, etienne

...

• int ret;

  parent = find_scmi_transport_device(dev); if (!parent) return -ENODEV;

• if (transport_dev_ops(parent)->of_get_channel)

• return transport_dev_ops(parent)->of_get_channel(parent, channel);
  

• ret = scmi_of_get_channel(parent, &priv->channel);
• if (ret == -EPROTONOSUPPORT) {

• /* Drivers without a get_channel operator don't need a channel ref */
  

• priv->channel = NULL;
  
  

• /* Drivers without a get_channel operator don't need a channel ref */
• *channel = NULL;

• return 0;
  

• }

• return 0;

• return ret;

}

-int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,

• 	  struct scmi_msg *msg)
  

+/**

• • scmi_process_msg() - Send and process an SCMI message
• • Send a message to an SCMI server.
• • Caller sets scmi_msg::out_msg_sz to the output message buffer size.
• • @dev: SCMI agent device
• • @channel: Communication channel for the device
• • @msg: Message structure reference
• • On return, scmi_msg::out_msg_sz stores the response payload size.
• • Return: 0 on success and a negative errno on failure
• */

+static int scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,

• 	    struct scmi_msg *msg)
  

{ const struct scmi_agent_ops *ops;

• ops = transport_dev_ops(dev);
• if (ops->process_msg)

• return ops->process_msg(dev, channel, msg);
  

• else

• return -EPROTONOSUPPORT;
  

+}

+int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg) +{ struct udevice *parent;

• struct scmi_agent_proto_priv *priv = dev_get_parent_priv(dev);

  parent = find_scmi_transport_device(dev); if (!parent) return -ENODEV;

• ops = transport_dev_ops(parent);
• if (ops->process_msg)

• return ops->process_msg(parent, channel, msg);
  

• return -EPROTONOSUPPORT;

• return scmi_process_msg(parent, priv->channel, msg);

}

UCLASS_DRIVER(scmi_agent) = { .id = UCLASS_SCMI_AGENT, .name = "scmi_agent", .post_bind = scmi_bind_protocols,

• .per_device_plat_auto = sizeof(struct scmi_agent_priv),

Typo: this added line belong to patch 04/12.

Regards, Etienne

...

• .per_child_auto = sizeof(struct scmi_agent_proto_priv *),

}; diff --git a/drivers/power/regulator/scmi_regulator.c b/drivers/power/regulator/scmi_regulator.c index 801148036ff6..08918b20872c 100644 --- a/drivers/power/regulator/scmi_regulator.c +++ b/drivers/power/regulator/scmi_regulator.c @@ -25,18 +25,9 @@ struct scmi_regulator_platdata { u32 domain_id; };

-/**

• • struct scmi_regulator_priv - Private data for SCMI voltage regulator
• • @channel: Reference to the SCMI channel to use
• */

-struct scmi_regulator_priv {

• struct scmi_channel *channel;

-};

static int scmi_voltd_set_enable(struct udevice *dev, bool enable) { struct scmi_regulator_platdata *pdata = dev_get_plat(dev);

• struct scmi_regulator_priv *priv = dev_get_priv(dev); struct scmi_voltd_config_set_in in = { .domain_id = pdata->domain_id, .config = enable ? SCMI_VOLTD_CONFIG_ON : SCMI_VOLTD_CONFIG_OFF,

@@ -47,7 +38,7 @@ static int scmi_voltd_set_enable(struct udevice *dev, bool enable) in, out); int ret;

• ret = devm_scmi_process_msg(dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(dev, &msg); if (ret) return ret;

@@ -57,7 +48,6 @@ static int scmi_voltd_set_enable(struct udevice *dev, bool enable) static int scmi_voltd_get_enable(struct udevice *dev) { struct scmi_regulator_platdata *pdata = dev_get_plat(dev);

• struct scmi_regulator_priv *priv = dev_get_priv(dev); struct scmi_voltd_config_get_in in = { .domain_id = pdata->domain_id, };

@@ -67,7 +57,7 @@ static int scmi_voltd_get_enable(struct udevice *dev) in, out); int ret;

• ret = devm_scmi_process_msg(dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(dev, &msg); if (ret < 0) return ret;

@@ -80,7 +70,6 @@ static int scmi_voltd_get_enable(struct udevice *dev)

static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV) {

• struct scmi_regulator_priv *priv = dev_get_priv(dev); struct scmi_regulator_platdata *pdata = dev_get_plat(dev); struct scmi_voltd_level_set_in in = { .domain_id = pdata->domain_id,

@@ -92,7 +81,7 @@ static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV) in, out); int ret;

• ret = devm_scmi_process_msg(dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(dev, &msg); if (ret < 0) return ret;

@@ -101,7 +90,6 @@ static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)

static int scmi_voltd_get_voltage_level(struct udevice *dev) {

• struct scmi_regulator_priv *priv = dev_get_priv(dev); struct scmi_regulator_platdata *pdata = dev_get_plat(dev); struct scmi_voltd_level_get_in in = { .domain_id = pdata->domain_id,

@@ -112,7 +100,7 @@ static int scmi_voltd_get_voltage_level(struct udevice *dev) in, out); int ret;

• ret = devm_scmi_process_msg(dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(dev, &msg); if (ret < 0) return ret;

@@ -140,7 +128,6 @@ static int scmi_regulator_of_to_plat(struct udevice *dev) static int scmi_regulator_probe(struct udevice *dev) { struct scmi_regulator_platdata *pdata = dev_get_plat(dev);

• struct scmi_regulator_priv *priv = dev_get_priv(dev); struct scmi_voltd_attr_in in = { 0 }; struct scmi_voltd_attr_out out = { 0 }; struct scmi_msg scmi_msg = {

@@ -153,14 +140,14 @@ static int scmi_regulator_probe(struct udevice *dev) }; int ret;

• ret = devm_scmi_of_get_channel(dev->parent, &priv->channel);

• ret = devm_scmi_of_get_channel(dev); if (ret) return ret;

  /* Check voltage domain is known from SCMI server */ in.domain_id = pdata->domain_id;

• ret = devm_scmi_process_msg(dev, priv->channel, &scmi_msg);

• ret = devm_scmi_process_msg(dev, &scmi_msg); if (ret) { dev_err(dev, "Failed to query voltage domain %u: %d\n", pdata->domain_id, ret);

@@ -184,7 +171,6 @@ U_BOOT_DRIVER(scmi_regulator) = { .probe = scmi_regulator_probe, .of_to_plat = scmi_regulator_of_to_plat, .plat_auto = sizeof(struct scmi_regulator_platdata),

• .priv_auto = sizeof(struct scmi_regulator_priv *),

};

static int scmi_regulator_bind(struct udevice *dev) @@ -209,4 +195,5 @@ U_BOOT_DRIVER(scmi_voltage_domain) = { .name = "scmi_voltage_domain", .id = UCLASS_NOP, .bind = scmi_regulator_bind,

• .per_child_auto = sizeof(struct scmi_agent_proto_priv *),

}; diff --git a/drivers/reset/reset-scmi.c b/drivers/reset/reset-scmi.c index 122556162ec3..b76711f0a8fb 100644 --- a/drivers/reset/reset-scmi.c +++ b/drivers/reset/reset-scmi.c @@ -13,17 +13,8 @@ #include <scmi_protocols.h> #include <asm/types.h>

-/**

• • struct scmi_reset_priv - Private data for SCMI reset controller
• • @channel: Reference to the SCMI channel to use
• */

-struct scmi_reset_priv {

• struct scmi_channel *channel;

-};

static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert) {

• struct scmi_reset_priv *priv = dev_get_priv(rst->dev); struct scmi_rd_reset_in in = { .domain_id = rst->id, .flags = assert_not_deassert ? SCMI_RD_RESET_FLAG_ASSERT : 0,

@@ -35,7 +26,7 @@ static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert) in, out); int ret;

• ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(rst->dev, &msg); if (ret) return ret;

@@ -54,7 +45,6 @@ static int scmi_reset_deassert(struct reset_ctl *rst)

static int scmi_reset_request(struct reset_ctl *rst) {

• struct scmi_reset_priv *priv = dev_get_priv(rst->dev); struct scmi_rd_attr_in in = { .domain_id = rst->id, };

@@ -68,7 +58,7 @@ static int scmi_reset_request(struct reset_ctl *rst) * We don't really care about the attribute, just check * the reset domain exists. */

• ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);

• ret = devm_scmi_process_msg(rst->dev, &msg); if (ret) return ret;

@@ -83,9 +73,7 @@ static const struct reset_ops scmi_reset_domain_ops = {

static int scmi_reset_probe(struct udevice *dev) {

• struct scmi_reset_priv *priv = dev_get_priv(dev);
• return devm_scmi_of_get_channel(dev, &priv->channel);

• return devm_scmi_of_get_channel(dev);

}

U_BOOT_DRIVER(scmi_reset_domain) = { @@ -93,5 +81,4 @@ U_BOOT_DRIVER(scmi_reset_domain) = { .id = UCLASS_RESET, .ops = &scmi_reset_domain_ops, .probe = scmi_reset_probe,

• .priv_auto = sizeof(struct scmi_reset_priv *),

}; diff --git a/include/scmi_agent.h b/include/scmi_agent.h index ee6286366df7..577892029ff8 100644 --- a/include/scmi_agent.h +++ b/include/scmi_agent.h @@ -15,6 +15,14 @@ struct udevice; struct scmi_channel;

+/**

• • struct scmi_agent_proto_priv - Private data in device for SCMI agent
• • @channel: Reference to the SCMI channel to use
• */

+struct scmi_agent_proto_priv {

• struct scmi_channel *channel;

+};

/*

• struct scmi_msg - Context of a SCMI message sent and the response received

@@ -49,10 +57,9 @@ struct scmi_msg {

• devm_scmi_of_get_channel() - Get SCMI channel handle from SCMI agent DT node
• @dev: Device requesting a channel

• • @channel: Output reference to the SCMI channel upon success
  • @return 0 on success and a negative errno on failure
  */

-int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel); +int devm_scmi_of_get_channel(struct udevice *dev);

/**

• devm_scmi_process_msg() - Send and process an SCMI message

@@ -62,12 +69,10 @@ int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)

• On return, scmi_msg::out_msg_sz stores the response payload size.
• @dev: SCMI device

• • @channel: Communication channel for the device
  • @msg: Message structure reference
  • Return: 0 on success and a negative errno on failure
  */

-int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,

• 	  struct scmi_msg *msg);
  

+int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg);

/**

• scmi_to_linux_errno() - Convert an SCMI error code into a Linux errno code

-- 2.41.0