Re: [PATCH v2 5/5] clk: scmi: register scmi clocks with CCF

Hi Etienne,

On 2/21/22 3:22 AM, Etienne Carriere wrote:

Implements SCMI APIs to retrieve the number exposed SCMI clocks using SCMI_PROTOCOL_ATTRIBUTES messages and the names of the clocks using SCMI_CLOCK_ATTRIBUTES messages.

This change updates sandbox SCMI clock test driver to manage these 2 new message IDs.

Cc: Lukasz Majewski lukma@denx.de Cc: Sean Anderson seanga2@gmail.com Cc: Clement Leger clement.leger@bootlin.com Cc: Patrick Delaunay patrick.delaunay@foss.st.com Reviewed-by: Patrick Delaunay patrick.delaunay@foss.st.com Signed-off-by: Gabriel Fernandez gabriel.fernandez@st.com Signed-off-by: Etienne Carriere etienne.carriere@linaro.org

---

Changes since v1:

• Remove Series-links tag and apply R-b tag.

---

drivers/clk/clk_scmi.c | 90 ++++++++++++++++++++++ drivers/firmware/scmi/sandbox-scmi_agent.c | 53 +++++++++++++ include/scmi_protocols.h | 43 +++++++++++ 3 files changed, 186 insertions(+)

diff --git a/drivers/clk/clk_scmi.c b/drivers/clk/clk_scmi.c index 42fbab0d21..57022685e2 100644 --- a/drivers/clk/clk_scmi.c +++ b/drivers/clk/clk_scmi.c @@ -11,6 +11,52 @@ #include <scmi_agent.h> #include <scmi_protocols.h> #include <asm/types.h> +#include <linux/clk-provider.h>

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

• struct scmi_clk_protocol_attr_out out;
• struct scmi_msg msg = {

• .protocol_id = SCMI_PROTOCOL_ID_CLOCK,
  

• .message_id = SCMI_PROTOCOL_ATTRIBUTES,
  

• .out_msg = (u8 *)&out,
  

• .out_msg_sz = sizeof(out),
  

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

• return ret;
  

• *num_clocks = out.attributes & SCMI_CLK_PROTO_ATTR_COUNT_MASK;
• return 0;

+}

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

nit: scmi_clk_get_attribute

+{

• struct scmi_clk_attribute_in in = {

• .clock_id = clkid,
  

• };
• struct scmi_clk_attribute_out out;
• struct scmi_msg msg = {

• .protocol_id = SCMI_PROTOCOL_ID_CLOCK,
  

• .message_id = SCMI_CLOCK_ATTRIBUTES,
  

• .in_msg = (u8 *)&in,
  

• .in_msg_sz = sizeof(in),
  

• .out_msg = (u8 *)&out,
  

• .out_msg_sz = sizeof(out),
  

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

• return ret;
  

• *name = out.clock_name;
• return 0;

+}

static int scmi_clk_gate(struct clk *clk, int enable) { @@ -88,6 +134,49 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate) return scmi_clk_get_rate(clk); }

+static int scmi_clk_probe(struct udevice *dev) +{

• struct clk *clk;
• size_t num_clocks, i;
• int ret;
• if (!CONFIG_IS_ENABLED(CLK_CCF))

• return 0;
  

• /* register CCF children: CLK UCLASS, no probed again */
• if (device_get_uclass_id(dev->parent) == UCLASS_CLK)

• return 0;
  

• ret = scmi_clk_get_num_clock(dev, &num_clocks);
• if (ret)

• return ret;
  

• for (i = 0; i < num_clocks; i++) {

• char *name;
  

• if (!scmi_clk_get_attibute(dev, i, &name)) {
  

• 	char *clock_name = strdup(name);
  

• 	clk = kzalloc(sizeof(*clk), GFP_KERNEL);
  

• 	if (!clk || !clock_name)
  

• 		ret = -ENOMEM;
  

• 	else
  

• 		ret = clk_register(clk, dev->driver->name,
  

• 				   clock_name, dev->name);
  

• 	if (ret) {
  

• 		free(clk);
  

• 		free(clock_name);
  

• 		return ret;
  

• 	}
  

• 	clk_dm(i, clk);
  

• }
  

• }
• return 0;

+}

So why not call scmi_clk_get_num_clock during probe() and then check against it in xlate? I don't really see why we need CCF. This also means you don't have a driver with copies of itself as children, and is lighter on memory.

--Sean

static const struct clk_ops scmi_clk_ops = { .enable = scmi_clk_enable, .disable = scmi_clk_disable, @@ -99,4 +188,5 @@ U_BOOT_DRIVER(scmi_clock) = { .name = "scmi_clk", .id = UCLASS_CLK, .ops = &scmi_clk_ops,

• .probe = &scmi_clk_probe, };

diff --git a/drivers/firmware/scmi/sandbox-scmi_agent.c b/drivers/firmware/scmi/sandbox-scmi_agent.c index fc717a8aea..c555164d19 100644 --- a/drivers/firmware/scmi/sandbox-scmi_agent.c +++ b/drivers/firmware/scmi/sandbox-scmi_agent.c @@ -114,6 +114,55 @@ static struct sandbox_scmi_voltd *get_scmi_voltd_state(uint domain_id)

• Sandbox SCMI agent ops

*/

+static int sandbox_scmi_clock_protocol_attribs(struct udevice *dev,

• 			       struct scmi_msg *msg)
  

+{

• struct scmi_clk_protocol_attr_out *out = NULL;
• if (!msg->out_msg || msg->out_msg_sz < sizeof(*out))

• return -EINVAL;
  

• out = (struct scmi_clk_protocol_attr_out *)msg->out_msg;
• out->attributes = ARRAY_SIZE(scmi_clk);
• out->status = SCMI_SUCCESS;
• return 0;

+}

+static int sandbox_scmi_clock_attribs(struct udevice *dev, struct scmi_msg *msg) +{

• struct scmi_clk_attribute_in *in = NULL;
• struct scmi_clk_attribute_out *out = NULL;
• struct sandbox_scmi_clk *clk_state = NULL;
• int ret;
• if (!msg->in_msg || msg->in_msg_sz < sizeof(*in) ||

•    !msg->out_msg || msg->out_msg_sz < sizeof(*out))
  

• return -EINVAL;
  

• in = (struct scmi_clk_attribute_in *)msg->in_msg;
• out = (struct scmi_clk_attribute_out *)msg->out_msg;
• clk_state = get_scmi_clk_state(in->clock_id);
• if (!clk_state) {

• dev_err(dev, "Unexpected clock ID %u\n", in->clock_id);
  

• out->status = SCMI_NOT_FOUND;
  

• } else {

• memset(out, 0, sizeof(*out));
  

• if (clk_state->enabled)
  

• 	out->attributes = 1;
  

• ret = snprintf(out->clock_name, sizeof(out->clock_name),
  

• 	       "clk%u", in->clock_id);
  

• assert(ret > 0 && ret < sizeof(out->clock_name));
  

• out->status = SCMI_SUCCESS;
  

• }
• return 0;

+} static int sandbox_scmi_clock_rate_set(struct udevice *dev, struct scmi_msg *msg) { @@ -427,6 +476,10 @@ static int sandbox_scmi_test_process_msg(struct udevice *dev, switch (msg->protocol_id) { case SCMI_PROTOCOL_ID_CLOCK: switch (msg->message_id) {

• case SCMI_PROTOCOL_ATTRIBUTES:
  

• 	return sandbox_scmi_clock_protocol_attribs(dev, msg);
  

• case SCMI_CLOCK_ATTRIBUTES:
  

• 	return sandbox_scmi_clock_attribs(dev, msg);
  

  case SCMI_CLOCK_RATE_SET: return sandbox_scmi_clock_rate_set(dev, msg); case SCMI_CLOCK_RATE_GET:

diff --git a/include/scmi_protocols.h b/include/scmi_protocols.h index ef26e72176..a220cb2a91 100644 --- a/include/scmi_protocols.h +++ b/include/scmi_protocols.h @@ -40,22 +40,65 @@ enum scmi_status_code { SCMI_PROTOCOL_ERROR = -10, };

+/*

• • Generic message IDs
• */

+enum scmi_discovery_id {

• SCMI_PROTOCOL_VERSION = 0x0,
• SCMI_PROTOCOL_ATTRIBUTES = 0x1,
• SCMI_PROTOCOL_MESSAGE_ATTRIBUTES = 0x2,

+};

• /*

  • SCMI Clock Protocol

  */

  enum scmi_clock_message_id {

• SCMI_CLOCK_ATTRIBUTES = 0x3, SCMI_CLOCK_RATE_SET = 0x5, SCMI_CLOCK_RATE_GET = 0x6, SCMI_CLOCK_CONFIG_SET = 0x7, };

+#define SCMI_CLK_PROTO_ATTR_COUNT_MASK GENMASK(15, 0) #define SCMI_CLK_RATE_ASYNC_NOTIFY BIT(0) #define SCMI_CLK_RATE_ASYNC_NORESP (BIT(0) | BIT(1)) #define SCMI_CLK_RATE_ROUND_DOWN 0 #define SCMI_CLK_RATE_ROUND_UP BIT(2) #define SCMI_CLK_RATE_ROUND_CLOSEST BIT(3)

+#define SCMI_CLOCK_NAME_LENGTH_MAX 16

+/**

• • struct scmi_clk_get_nb_out - Response for SCMI_PROTOCOL_ATTRIBUTES command
• • @status: SCMI command status
• • @attributes: Attributes of the clock protocol, mainly number of clocks exposed
• */

+struct scmi_clk_protocol_attr_out {

• s32 status;
• u32 attributes;

+};

+/**

• • struct scmi_clk_attribute_in - Message payload for SCMI_CLOCK_ATTRIBUTES command
• • @clock_id: SCMI clock ID
• */

+struct scmi_clk_attribute_in {

• u32 clock_id;

+};

+/**

• • struct scmi_clk_get_nb_out - Response payload for SCMI_CLOCK_ATTRIBUTES command
• • @status: SCMI command status
• • @attributes: clock attributes
• • @clock_name: name of the clock
• */

+struct scmi_clk_attribute_out {

• s32 status;
• u32 attributes;
• char clock_name[SCMI_CLOCK_NAME_LENGTH_MAX];

+};

• /**
  • struct scmi_clk_state_in - Message payload for CLOCK_CONFIG_SET command
  • @clock_id: SCMI clock ID