Re: [PATCH v7 3/3] remoteproc: k3-r5: Use separate compatible string for TI AM62x SoC family

Devarsh Thakkar <devarsht@xxxxxx> · Tue, 28 Mar 2023 21:38:30 +0530

Hi Roger,

On 28/03/23 13:22, Roger Quadros wrote:
Hi Devarsh,

On 17/03/2023 18:17, Mathieu Poirier wrote:
On Fri, Mar 10, 2023 at 09:55:44PM +0530, Devarsh Thakkar wrote:
AM62 and AM62A SoCs use single core R5F which is a new scenario
different than the one being used with CLUSTER_MODE_SINGLECPU which is
for utilizing a single core from a set of cores available in R5F cluster
present in the SoC.

To support this single core scenario map it with newly defined
CLUSTER_MODE_SINGLECORE and use it when compatible is set to
ti,am62-r5fss.

Also set PROC_BOOT_CFG_FLAG_R5_SINGLE_CORE config for
CLUSTER_MODE_SINGLECORE too as it is required by R5 core when it is
being as general purpose core instead of device manager.

Signed-off-by: Devarsh Thakkar <devarsht@xxxxxx>
---
V2:
- Fix indentation and ordering issues as per review comments
V3:
- Change CLUSTER_MODE_NONE value to -1
V4:
- No change
V5:
- No change (fixing typo in email address)
V6:
    - Use CLUSTER_MODE_SINGLECORE for AM62x
    - Set PROC_BOOT_CFG_FLAG_R5_SINGLE_CORE for single core.
V7:
    - Simplify and rebase on top of base commit "[PATCH v7] remoteproc: k3-r5: Simplify cluster
      mode setting"
---
  drivers/remoteproc/ti_k3_r5_remoteproc.c | 59 +++++++++++++++++++-----
  1 file changed, 48 insertions(+), 11 deletions(-)

diff --git a/drivers/remoteproc/ti_k3_r5_remoteproc.c b/drivers/remoteproc/ti_k3_r5_remoteproc.c
index c2ec0f432921..df32f6bc4325 100644
--- a/drivers/remoteproc/ti_k3_r5_remoteproc.c
+++ b/drivers/remoteproc/ti_k3_r5_remoteproc.c
@@ -71,14 +71,16 @@ struct k3_r5_mem {
  /*
   * All cluster mode values are not applicable on all SoCs. The following
   * are the modes supported on various SoCs:
- *   Split mode      : AM65x, J721E, J7200 and AM64x SoCs
- *   LockStep mode   : AM65x, J721E and J7200 SoCs
- *   Single-CPU mode : AM64x SoCs only
+ *   Split mode       : AM65x, J721E, J7200 and AM64x SoCs
+ *   LockStep mode    : AM65x, J721E and J7200 SoCs
+ *   Single-CPU mode  : AM64x SoCs only
+ *   Single-Core mode : AM62x, AM62A SoCs
   */
  enum cluster_mode {
  	CLUSTER_MODE_SPLIT = 0,
  	CLUSTER_MODE_LOCKSTEP,
  	CLUSTER_MODE_SINGLECPU,
+	CLUSTER_MODE_SINGLECORE

What is the difference in device driver behaviour between
SINGLECPU and SINGLECORE?

Yeah there is quite a bit of common code flow between the two but the 
fundamental difference is that you use CLUSTER_MODE_SINGLECPU when
you have two R5F cores but you want to use only single R5F core albeit
with using TCM of both the cores whereas CLUSTER_MODE_SINGLECORE is
for the scenario where you have single core R5F's only.

Also the bindings for CLUSTER_MODE_SINGLECPU are already upstream so did
not want to break them either : 
https://gitlab.com/linux-kernel/linux-next/-/blob/next-20230328/Documentation/devicetree/bindings/remoteproc/ti%2Ck3-r5f-rproc.yaml#L20.

Regards
Devarsh

If there is no difference then you should not introduce
a new enum. >
  };
  
  /**
@@ -86,11 +88,13 @@ enum cluster_mode {
   * @tcm_is_double: flag to denote the larger unified TCMs in certain modes
   * @tcm_ecc_autoinit: flag to denote the auto-initialization of TCMs for ECC
   * @single_cpu_mode: flag to denote if SoC/IP supports Single-CPU mode
+ * @is_single_core: flag to denote if SoC/IP has only single core R5
   */
  struct k3_r5_soc_data {
  	bool tcm_is_double;
  	bool tcm_ecc_autoinit;
  	bool single_cpu_mode;
+	bool is_single_core;
  };
  
  /**
@@ -838,7 +842,8 @@ static int k3_r5_rproc_configure(struct k3_r5_rproc *kproc)
  
  	core0 = list_first_entry(&cluster->cores, struct k3_r5_core, elem);
  	if (cluster->mode == CLUSTER_MODE_LOCKSTEP ||
-	    cluster->mode == CLUSTER_MODE_SINGLECPU) {
+	    cluster->mode == CLUSTER_MODE_SINGLECPU ||
+	    cluster->mode == CLUSTER_MODE_SINGLECORE) {
  		core = core0;
  	} else {
  		core = kproc->core;
@@ -877,7 +882,8 @@ static int k3_r5_rproc_configure(struct k3_r5_rproc *kproc)
  		 * with the bit configured, so program it only on
  		 * permitted cores
  		 */
-		if (cluster->mode == CLUSTER_MODE_SINGLECPU) {
+		if (cluster->mode == CLUSTER_MODE_SINGLECPU ||
+		    cluster->mode == CLUSTER_MODE_SINGLECORE) {
  			set_cfg = PROC_BOOT_CFG_FLAG_R5_SINGLE_CORE;
  		} else {
  			/*
@@ -1069,6 +1075,7 @@ static void k3_r5_adjust_tcm_sizes(struct k3_r5_rproc *kproc)
  
  	if (cluster->mode == CLUSTER_MODE_LOCKSTEP ||
  	    cluster->mode == CLUSTER_MODE_SINGLECPU ||
+	    cluster->mode == CLUSTER_MODE_SINGLECORE ||
  	    !cluster->soc_data->tcm_is_double)
  		return;
  
@@ -1145,6 +1152,8 @@ static int k3_r5_rproc_configure_mode(struct k3_r5_rproc *kproc)
  	if (cluster->soc_data->single_cpu_mode) {
  		mode = cfg & PROC_BOOT_CFG_FLAG_R5_SINGLE_CORE ?
  				CLUSTER_MODE_SINGLECPU : CLUSTER_MODE_SPLIT;
+	} else if (cluster->soc_data->is_single_core) {
+		mode = CLUSTER_MODE_SINGLECORE;

I have commented twice on this before - whether it is soc_data->single_cpu_mode or
soc_data->is_single_core, I don't want to see them used elsewhere than in a
single function.  Either in probe() or another function, use them once to set
cluster->mode and never again.

I will silently drop any other patchset that doesn't address this.

  	} else {
  		mode = cfg & PROC_BOOT_CFG_FLAG_R5_LOCKSTEP ?
  				CLUSTER_MODE_LOCKSTEP : CLUSTER_MODE_SPLIT;
@@ -1264,9 +1273,12 @@ static int k3_r5_cluster_rproc_init(struct platform_device *pdev)
  			goto err_add;
  		}
  
-		/* create only one rproc in lockstep mode or single-cpu mode */
+		/* create only one rproc in lockstep, single-cpu or
+		 * single core mode
+		 */
  		if (cluster->mode == CLUSTER_MODE_LOCKSTEP ||
-		    cluster->mode == CLUSTER_MODE_SINGLECPU)
+		    cluster->mode == CLUSTER_MODE_SINGLECPU ||
+		    cluster->mode == CLUSTER_MODE_SINGLECORE)
  			break;
  	}
  
@@ -1709,19 +1721,33 @@ static int k3_r5_probe(struct platform_device *pdev)
  		/*
  		 * default to most common efuse configurations - Split-mode on AM64x
  		 * and LockStep-mode on all others
+		 * default to most common efuse configurations -
+		 * Split-mode on AM64x
+		 * Single core on AM62x
+		 * LockStep-mode on all others
  		 */
-		cluster->mode = data->single_cpu_mode ?
+		if (!data->is_single_core)
+			cluster->mode = data->single_cpu_mode ?
  					CLUSTER_MODE_SPLIT : CLUSTER_MODE_LOCKSTEP;
+		else
+			cluster->mode = CLUSTER_MODE_SINGLECORE;
  	}
  
-	if (cluster->mode == CLUSTER_MODE_SINGLECPU && !data->single_cpu_mode) {
+	if  ((cluster->mode == CLUSTER_MODE_SINGLECPU && !data->single_cpu_mode) ||
+	     (cluster->mode == CLUSTER_MODE_SINGLECORE && !data->is_single_core)) {
  		dev_err(dev, "Cluster mode = %d is not supported on this SoC\n", cluster->mode);
  		return -EINVAL;
  	}
  
  	num_cores = of_get_available_child_count(np);
-	if (num_cores != 2) {
-		dev_err(dev, "MCU cluster requires both R5F cores to be enabled, num_cores = %d\n",
+	if (num_cores != 2 && !data->is_single_core) {
+		dev_err(dev, "MCU cluster requires both R5F cores to be enabled but num_cores is set to = %d\n",
+			num_cores);
+		return -ENODEV;
+	}
+
+	if (num_cores != 1 && data->is_single_core) {
+		dev_err(dev, "SoC supports only single core R5 but num_cores is set to %d\n",
  			num_cores);
  		return -ENODEV;
  	}
@@ -1763,18 +1789,28 @@ static const struct k3_r5_soc_data am65_j721e_soc_data = {
  	.tcm_is_double = false,
  	.tcm_ecc_autoinit = false,
  	.single_cpu_mode = false,
+	.is_single_core = false,
  };
  
  static const struct k3_r5_soc_data j7200_j721s2_soc_data = {
  	.tcm_is_double = true,
  	.tcm_ecc_autoinit = true,
  	.single_cpu_mode = false,
+	.is_single_core = false,
  };
  
  static const struct k3_r5_soc_data am64_soc_data = {
  	.tcm_is_double = true,
  	.tcm_ecc_autoinit = true,
  	.single_cpu_mode = true,
+	.is_single_core = false,
+};
+
+static const struct k3_r5_soc_data am62_soc_data = {
+	.tcm_is_double = false,
+	.tcm_ecc_autoinit = true,
+	.single_cpu_mode = false,
+	.is_single_core = true,
  };
  
  static const struct of_device_id k3_r5_of_match[] = {
@@ -1782,6 +1818,7 @@ static const struct of_device_id k3_r5_of_match[] = {
  	{ .compatible = "ti,j721e-r5fss", .data = &am65_j721e_soc_data, },
  	{ .compatible = "ti,j7200-r5fss", .data = &j7200_j721s2_soc_data, },
  	{ .compatible = "ti,am64-r5fss",  .data = &am64_soc_data, },
+	{ .compatible = "ti,am62-r5fss",  .data = &am62_soc_data, },
  	{ .compatible = "ti,j721s2-r5fss",  .data = &j7200_j721s2_soc_data, },
  	{ /* sentinel */ },
  };
--
2.34.1


cheers,
-roger






