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Message-ID: <f08e550b-2f15-0f84-c0ca-05e0b803481a@kernel.org>
Date:   Tue, 28 Mar 2023 10:52:55 +0300
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Subject: Re: [PATCH v7 3/3] remoteproc: k3-r5: Use separate compatible string
 for TI AM62x SoC family
Content-Language: en-US
To:     Mathieu Poirier <mathieu.poirier@linaro.org>,
        Devarsh Thakkar <devarsht@ti.com>
Cc:     andersson@kernel.org, devicetree@vger.kernel.org,
        p.zabel@pengutronix.de, linux-remoteproc@vger.kernel.org,
        robh+dt@kernel.org, linux-kernel@vger.kernel.org,
        krzysztof.kozlowski+dt@linaro.org, s-anna@ti.com, hnagalla@ti.com,
        praneeth@ti.com, nm@ti.com, vigneshr@ti.com, a-bhatia1@ti.com,
        j-luthra@ti.com
References: <20230310162544.3468365-1-devarsht@ti.com>
 <20230310162544.3468365-4-devarsht@ti.com> <20230317161757.GA2471094@p14s>
From:   Roger Quadros <rogerq@kernel.org>
In-Reply-To: <20230317161757.GA2471094@p14s>
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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@ti.com>
>> ---
>> 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?

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