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Date:   Mon, 04 Sep 2023 22:44:44 +0200
From:   Martin Botka <martin.botka@somainline.org>
Subject: Re: [PATCH 4/6] cpufreq: sun50i: Add H616 support
To:     Andre Przywara <andre.przywara@arm.com>
Cc:     Mark Rutland <mark.rutland@arm.com>,
        Lorenzo Pieralisi <lpieralisi@kernel.org>,
        Sudeep Holla <sudeep.holla@arm.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Yangtao Li <tiny.windzz@gmail.com>,
        Chen-Yu Tsai <wens@csie.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Samuel Holland <samuel@sholland.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-pm@vger.kernel.org, linux-sunxi@lists.linux.dev,
        devicetree@vger.kernel.org, Alan Ma <tech@biqu3d.com>,
        Luke Harrison <bttuniversity@biqu3d.com>,
        Marijn Suijten <marijn.suijten@somainline.org>,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@somainline.org>,
        Konrad Dybcio <konrad.dybcio@somainline.org>,
        Rogerio Goncalves <rogerlz@gmail.com>,
        Martin Botka <martin@biqu3d.com>
Message-Id: <KYAH0S.DN4CQO1UCNM72@somainline.org>
In-Reply-To: <20230904214108.317413f9@slackpad.lan>
References: <20230904-cpufreq-h616-v1-0-b8842e525c43@somainline.org>
        <20230904-cpufreq-h616-v1-4-b8842e525c43@somainline.org>
        <20230904214108.317413f9@slackpad.lan>
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On Mon, Sep 4 2023 at 09:41:08 PM +01:00:00, Andre Przywara 
<andre.przywara@arm.com> wrote:
> On Mon, 04 Sep 2023 17:57:04 +0200
> Martin Botka <martin.botka@somainline.org> wrote:
> 
> Hi,
> 
>>  AllWinner H616 SoC has few revisions that support different list
>>  of uV and frequencies.
>> 
>>  Some revisions have the same NVMEM value and thus we have to check
>>  the SoC revision from SMCCC to differentiate between them.
> 
> So this patch is a bit hard to read, as it combines two things: the
> refactoring and the actual H616 bits. Can you please split this up,
> with a first patch just introducing struct sunxi_cpufreq_soc_data and
> moving the existing code into the separate xlate function, and all the
> other required changes? Then having a second patch adding the H616
> bits on top? This makes review easier, as the first patch should not
> change any behaviour, and the second patch just focuses on the new 
> H616
> bits.
Yea it is. I will split them up in V2.
> 
> Cheers,
> Andre
> 
>> 
>>  Signed-off-by: Martin Botka <martin.botka@somainline.org>
>>  ---
>>   drivers/cpufreq/sun50i-cpufreq-nvmem.c | 149 
>> ++++++++++++++++++++++++++++-----
>>   1 file changed, 126 insertions(+), 23 deletions(-)
>> 
>>  diff --git a/drivers/cpufreq/sun50i-cpufreq-nvmem.c 
>> b/drivers/cpufreq/sun50i-cpufreq-nvmem.c
>>  index 4321d7bbe769..19c126fb081e 100644
>>  --- a/drivers/cpufreq/sun50i-cpufreq-nvmem.c
>>  +++ b/drivers/cpufreq/sun50i-cpufreq-nvmem.c
>>  @@ -10,6 +10,7 @@
>> 
>>   #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>> 
>>  +#include <linux/arm-smccc.h>
>>   #include <linux/cpu.h>
>>   #include <linux/module.h>
>>   #include <linux/nvmem-consumer.h>
>>  @@ -23,20 +24,94 @@
>>   #define NVMEM_MASK	0x7
>>   #define NVMEM_SHIFT	5
>> 
>>  +struct sunxi_cpufreq_soc_data {
>>  +	int (*efuse_xlate)(u32 *versions, u32 *efuse, char *name, size_t 
>> len);
>>  +	u8 ver_freq_limit;
>>  +};
>>  +
>>   static struct platform_device *cpufreq_dt_pdev, 
>> *sun50i_cpufreq_pdev;
>> 
>>  +static int sun50i_h616_efuse_xlate(u32 *versions, u32 *efuse, char 
>> *name, size_t len)
>>  +{
>>  +	int value = 0;
>>  +	u32 speedgrade = 0;
>>  +	u32 i;
>>  +	int ver_bits = arm_smccc_get_soc_id_revision();
>>  +
>>  +	if (len > 4) {
>>  +		pr_err("Invalid nvmem cell length\n");
>>  +		return -EINVAL;
>>  +	}
>>  +
>>  +	for (i = 0; i < len; i++)
>>  +		speedgrade |= (efuse[i] << (i * 8));
>>  +
>>  +	switch (speedgrade) {
>>  +	case 0x2000:
>>  +		value = 0;
>>  +		break;
>>  +	case 0x2400:
>>  +	case 0x7400:
>>  +	case 0x2c00:
>>  +	case 0x7c00:
>>  +		if (ver_bits <= 1) {
>>  +			/* ic version A/B */
>>  +			value = 1;
>>  +		} else {
>>  +			/* ic version C and later version */
>>  +			value = 2;
>>  +		}
>>  +		break;
>>  +	case 0x5000:
>>  +	case 0x5400:
>>  +	case 0x6000:
>>  +		value = 3;
>>  +		break;
>>  +	case 0x5c00:
>>  +		value = 4;
>>  +		break;
>>  +	case 0x5d00:
>>  +	default:
>>  +		value = 0;
>>  +	}
>>  +	*versions = (1 << value);
>>  +	snprintf(name, MAX_NAME_LEN, "speed%d", value);
>>  +	return 0;
>>  +}
>>  +
>>  +static int sun50i_h6_efuse_xlate(u32 *versions, u32 *efuse, char 
>> *name, size_t len)
>>  +{
>>  +	int efuse_value = (*efuse >> NVMEM_SHIFT) & NVMEM_MASK;
>>  +
>>  +	/*
>>  +	 * We treat unexpected efuse values as if the SoC was from
>>  +	 * the slowest bin. Expected efuse values are 1-3, slowest
>>  +	 * to fastest.
>>  +	 */
>>  +	if (efuse_value >= 1 && efuse_value <= 3)
>>  +		*versions = efuse_value - 1;
>>  +	else
>>  +		*versions = 0;
>>  +
>>  +	snprintf(name, MAX_NAME_LEN, "speed%d", *versions);
>>  +	return 0;
>>  +}
>>  +
>>   /**
>>    * sun50i_cpufreq_get_efuse() - Determine speed grade from efuse 
>> value
>>  + * @soc_data: Struct containing soc specific data & functions
>>    * @versions: Set to the value parsed from efuse
>>  + * @name: Set to the name of speed
>>    *
>>    * Returns 0 if success.
>>    */
>>  -static int sun50i_cpufreq_get_efuse(u32 *versions)
>>  +static int sun50i_cpufreq_get_efuse(const struct 
>> sunxi_cpufreq_soc_data *soc_data,
>>  +				    u32 *versions, char *name)
>>   {
>>   	struct nvmem_cell *speedbin_nvmem;
>>   	struct device_node *np;
>>   	struct device *cpu_dev;
>>  -	u32 *speedbin, efuse_value;
>>  +	u32 *speedbin;
>>   	size_t len;
>>   	int ret;
>> 
>>  @@ -48,9 +123,9 @@ static int sun50i_cpufreq_get_efuse(u32 
>> *versions)
>>   	if (!np)
>>   		return -ENOENT;
>> 
>>  -	ret = of_device_is_compatible(np,
>>  -				      "allwinner,sun50i-h6-operating-points");
>>  -	if (!ret) {
>>  +	if (of_device_is_compatible(np, 
>> "allwinner,sun50i-h6-operating-points")) {
>>  +	} else if (of_device_is_compatible(np, 
>> "allwinner,sun50i-h616-operating-points")) {
>>  +	} else {
>>   		of_node_put(np);
>>   		return -ENOENT;
>>   	}
>>  @@ -66,17 +141,9 @@ static int sun50i_cpufreq_get_efuse(u32 
>> *versions)
>>   	if (IS_ERR(speedbin))
>>   		return PTR_ERR(speedbin);
>> 
>>  -	efuse_value = (*speedbin >> NVMEM_SHIFT) & NVMEM_MASK;
>>  -
>>  -	/*
>>  -	 * We treat unexpected efuse values as if the SoC was from
>>  -	 * the slowest bin. Expected efuse values are 1-3, slowest
>>  -	 * to fastest.
>>  -	 */
>>  -	if (efuse_value >= 1 && efuse_value <= 3)
>>  -		*versions = efuse_value - 1;
>>  -	else
>>  -		*versions = 0;
>>  +	ret = soc_data->efuse_xlate(versions, speedbin, name, len);
>>  +	if (ret)
>>  +		return ret;
>> 
>>   	kfree(speedbin);
>>   	return 0;
>>  @@ -84,25 +151,30 @@ static int sun50i_cpufreq_get_efuse(u32 
>> *versions)
>> 
>>   static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev)
>>   {
>>  +	const struct of_device_id *match;
>>  +	const struct sunxi_cpufreq_soc_data *soc_data;
>>   	int *opp_tokens;
>>   	char name[MAX_NAME_LEN];
>>   	unsigned int cpu;
>>  -	u32 speed = 0;
>>  +	u32 version = 0;
>>   	int ret;
>> 
>>  +	match = dev_get_platdata(&pdev->dev);
>>  +	if (!match)
>>  +		return -EINVAL;
>>  +	soc_data = match->data;
>>  +
>>   	opp_tokens = kcalloc(num_possible_cpus(), sizeof(*opp_tokens),
>>   			     GFP_KERNEL);
>>   	if (!opp_tokens)
>>   		return -ENOMEM;
>> 
>>  -	ret = sun50i_cpufreq_get_efuse(&speed);
>>  +	ret = sun50i_cpufreq_get_efuse(match->data, &version, name);
>>   	if (ret) {
>>   		kfree(opp_tokens);
>>   		return ret;
>>   	}
>> 
>>  -	snprintf(name, MAX_NAME_LEN, "speed%d", speed);
>>  -
>>   	for_each_possible_cpu(cpu) {
>>   		struct device *cpu_dev = get_cpu_device(cpu);
>> 
>>  @@ -117,6 +189,16 @@ static int sun50i_cpufreq_nvmem_probe(struct 
>> platform_device *pdev)
>>   			pr_err("Failed to set prop name\n");
>>   			goto free_opp;
>>   		}
>>  +
>>  +		if (soc_data->ver_freq_limit) {
>>  +			opp_tokens[cpu] = dev_pm_opp_set_supported_hw(cpu_dev,
>>  +								  &version, 1);
>>  +			if (opp_tokens[cpu] < 0) {
>>  +				ret = opp_tokens[cpu];
>>  +				pr_err("Failed to set hw\n");
>>  +				goto free_opp;
>>  +			}
>>  +		}
>>   	}
>> 
>>   	cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", 
>> -1,
>>  @@ -132,6 +214,8 @@ static int sun50i_cpufreq_nvmem_probe(struct 
>> platform_device *pdev)
>>   free_opp:
>>   	for_each_possible_cpu(cpu)
>>   		dev_pm_opp_put_prop_name(opp_tokens[cpu]);
>>  +		if (soc_data->ver_freq_limit)
>>  +			dev_pm_opp_put_supported_hw(opp_tokens[cpu]);
>>   	kfree(opp_tokens);
>> 
>>   	return ret;
>>  @@ -140,12 +224,21 @@ static int sun50i_cpufreq_nvmem_probe(struct 
>> platform_device *pdev)
>>   static int sun50i_cpufreq_nvmem_remove(struct platform_device 
>> *pdev)
>>   {
>>   	int *opp_tokens = platform_get_drvdata(pdev);
>>  +	const struct of_device_id *match;
>>  +	const struct sunxi_cpufreq_soc_data *soc_data;
>>   	unsigned int cpu;
>> 
>>  +	match = dev_get_platdata(&pdev->dev);
>>  +	if (!match)
>>  +		return -EINVAL;
>>  +	soc_data = match->data;
>>  +
>>   	platform_device_unregister(cpufreq_dt_pdev);
>> 
>>   	for_each_possible_cpu(cpu)
>>   		dev_pm_opp_put_prop_name(opp_tokens[cpu]);
>>  +		if (soc_data->ver_freq_limit)
>>  +			dev_pm_opp_put_supported_hw(opp_tokens[cpu]);
>> 
>>   	kfree(opp_tokens);
>> 
>>  @@ -160,8 +253,18 @@ static struct platform_driver 
>> sun50i_cpufreq_driver = {
>>   	},
>>   };
>> 
>>  +static const struct sunxi_cpufreq_soc_data sun50i_h616_data = {
>>  +	.efuse_xlate = sun50i_h616_efuse_xlate,
>>  +	.ver_freq_limit = true,
>>  +};
>>  +
>>  +static const struct sunxi_cpufreq_soc_data sun50i_h6_data = {
>>  +	.efuse_xlate = sun50i_h6_efuse_xlate,
>>  +};
>>  +
>>   static const struct of_device_id sun50i_cpufreq_match_list[] = {
>>  -	{ .compatible = "allwinner,sun50i-h6" },
>>  +	{ .compatible = "allwinner,sun50i-h6", .data = &sun50i_h6_data },
>>  +	{ .compatible = "allwinner,sun50i-h616", .data = 
>> &sun50i_h616_data },
>>   	{}
>>   };
>>   MODULE_DEVICE_TABLE(of, sun50i_cpufreq_match_list);
>>  @@ -197,8 +300,8 @@ static int __init sun50i_cpufreq_init(void)
>>   		return ret;
>> 
>>   	sun50i_cpufreq_pdev =
>>  -		platform_device_register_simple("sun50i-cpufreq-nvmem",
>>  -						-1, NULL, 0);
>>  +		platform_device_register_data(NULL, "sun50i-cpufreq-nvmem",
>>  +						-1, match, sizeof(*match));
>>   	ret = PTR_ERR_OR_ZERO(sun50i_cpufreq_pdev);
>>   	if (ret == 0)
>>   		return 0;
>> 
>