Re: [PATCH 1/4] cpufreq: ti-cpufreq: add support for omap34xx and omap36xx

["H. Nikolaus Schaller" <hns@goldelico.com>]

> Am 07.09.2019 um 08:56 schrieb H. Nikolaus Schaller <hns@goldelico.com>:
> 
> This adds code and tables to read the silicon revision and
> eFuse (speed binned / 720 MHz grade) bits for selecting
> opp-v2 table entries.
> 
> Since these bits are not always part of the syscon register
> range (like for am33xx, am43, dra7), we add code to directly
> read the register values using ioremap() if syscon access fails.
> 
> The format of the opp-supported-hw entries is that it has
> two 32 bit bitfields. E.g.:
> 
> 	opp-supported-hw = <0xffffffff 3>
> 
> The first value is matched against the bit position of the
> silicon revision which is (see TRM)
> 
> omap34xx:
> BIT(0)	ES1.0
> BIT(1)	ES2.0
> BIT(2)	ES2.1
> BIT(3)	ES3.0
> BIT(4)	ES3.1
> BIT(7)	ES3.1.2
> 
> omap36xx:
> BIT(0)	ES1.0
> BIT(1)	ES1.1
> BIT(2)	ES1.2
> 
> The second value is matched against the speed grade eFuse:
> 
> BIT(0)	no high speed OPP
> BIT(1)	high speed OPP
> 
> This means for the example above that it is always enabled
> while e.g.
> 
> 	opp-supported-hw = <0x1 2>
> 
> enables the OPP only for ES1.0 BIT(0) and if the high speed
> eFuse is set BIT(1).
> 
> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
> ---
> drivers/cpufreq/ti-cpufreq.c | 91 +++++++++++++++++++++++++++++++++++-
> 1 file changed, 89 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/cpufreq/ti-cpufreq.c b/drivers/cpufreq/ti-cpufreq.c
> index 2ad1ae17932d..f2f58d689320 100644
> --- a/drivers/cpufreq/ti-cpufreq.c
> +++ b/drivers/cpufreq/ti-cpufreq.c
> @@ -31,6 +31,11 @@
> #define DRA7_EFUSE_OD_MPU_OPP			BIT(1)
> #define DRA7_EFUSE_HIGH_MPU_OPP			BIT(2)
> 
> +#define OMAP3_CONTROL_DEVICE_STATUS		0x4800244C
> +#define OMAP3_CONTROL_IDCODE			0x4830A204
> +#define OMAP34xx_ProdID_SKUID			0x4830A20C
> +#define OMAP3_SYSCON_BASE	(0x48000000 + 0x2000 + 0x270)
> +
> #define VERSION_COUNT				2
> 
> struct ti_cpufreq_data;
> @@ -84,6 +89,13 @@ static unsigned long dra7_efuse_xlate(struct ti_cpufreq_data *opp_data,
> 	return calculated_efuse;
> }
> 
> +static unsigned long omap3_efuse_xlate(struct ti_cpufreq_data *opp_data,
> +				      unsigned long efuse)
> +{
> +	/* OPP enable bit ("Speed Binned") */
> +	return BIT(efuse);
> +}
> +
> static struct ti_cpufreq_soc_data am3x_soc_data = {
> 	.efuse_xlate = amx3_efuse_xlate,
> 	.efuse_fallback = AM33XX_800M_ARM_MPU_MAX_FREQ,
> @@ -111,6 +123,56 @@ static struct ti_cpufreq_soc_data dra7_soc_data = {
> 	.multi_regulator = true,
> };
> 
> +/*
> + * OMAP35x TRM (SPRUF98K):
> + *  CONTROL_IDCODE (0x4830 A204) describes Silicon revisions.
> + *  Control OMAP Status Register 15:0 (Address 0x4800 244C)
> + *    to separate between omap3503, omap3515, omap3525, omap3530
> + *    and feature presence.
> + *    There are encodings for versions limited to 400/266MHz
> + *    but we ignore.
> + *    Not clear if this also holds for omap34xx.
> + *  some eFuse values e.g. CONTROL_FUSE_OPP1_VDD1
> + *    are stored in the SYSCON register range
> + *  Register 0x4830A20C [ProdID.SKUID] [0:3]
> + *    0x0 for normal 600/430MHz device.
> + *    0x8 for 720/520MHz device.
> + *    Not clear what omap34xx value is.
> + */
> +
> +static struct ti_cpufreq_soc_data omap34xx_soc_data = {
> +	.efuse_xlate = omap3_efuse_xlate,
> +	.efuse_offset = OMAP34xx_ProdID_SKUID - OMAP3_SYSCON_BASE,
> +	.efuse_shift = 3,
> +	.efuse_mask = BIT(3),
> +	.rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE,
> +	.multi_regulator = false,
> +};
> +
> +/*
> + * AM/DM37x TRM (SPRUGN4M)
> + *  CONTROL_IDCODE (0x4830 A204) describes Silicon revisions.
> + *  Control Device Status Register 15:0 (Address 0x4800 244C)
> + *    to separate between am3703, am3715, dm3725, dm3730
> + *    and feature presence.
> + *   Speed Binned = Bit 9
> + *     0 800/600 MHz
> + *     1 1000/800 MHz
> + *  some eFuse values e.g. CONTROL_FUSE_OPP 1G_VDD1
> + *    are stored in the SYSCON register range.
> + *  There is no 0x4830A20C [ProdID.SKUID] register (exists but
> + *    seems to always read as 0).
> + */
> +
> +static struct ti_cpufreq_soc_data omap36xx_soc_data = {
> +	.efuse_xlate = omap3_efuse_xlate,
> +	.efuse_offset = OMAP3_CONTROL_DEVICE_STATUS - OMAP3_SYSCON_BASE,
> +	.efuse_shift = 9,
> +	.efuse_mask = BIT(9),
> +	.rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE,
> +	.multi_regulator = false,
> +};
> +
> /**
>  * ti_cpufreq_get_efuse() - Parse and return efuse value present on SoC
>  * @opp_data: pointer to ti_cpufreq_data context
> @@ -127,7 +189,17 @@ static int ti_cpufreq_get_efuse(struct ti_cpufreq_data *opp_data,
> 
> 	ret = regmap_read(opp_data->syscon, opp_data->soc_data->efuse_offset,
> 			  &efuse);
> -	if (ret) {
> +	if (ret == -EIO) {
> +		/* not a syscon register! */
> +		void __iomem *regs = ioremap(OMAP3_SYSCON_BASE +
> +				opp_data->soc_data->efuse_offset, 4);
> +
> +		if (!regs)
> +			return -ENOMEM;
> +		efuse = readl(regs);
> +		iounmap(regs);
> +		}
> +	else if (ret) {
> 		dev_err(dev,
> 			"Failed to read the efuse value from syscon: %d\n",
> 			ret);
> @@ -158,7 +230,17 @@ static int ti_cpufreq_get_rev(struct ti_cpufreq_data *opp_data,
> 
> 	ret = regmap_read(opp_data->syscon, opp_data->soc_data->rev_offset,
> 			  &revision);
> -	if (ret) {
> +	if (ret == -EIO) {
> +		/* not a syscon register! */
> +		void __iomem *regs = ioremap(OMAP3_SYSCON_BASE +
> +				opp_data->soc_data->rev_offset, 4);
> +
> +		if (!regs)
> +			return -ENOMEM;
> +		revision = readl(regs);
> +		iounmap(regs);
> +		}
> +	else if (ret) {
> 		dev_err(dev,
> 			"Failed to read the revision number from syscon: %d\n",
> 			ret);
> @@ -190,6 +272,11 @@ static const struct of_device_id ti_cpufreq_of_match[] = {
> 	{ .compatible = "ti,am33xx", .data = &am3x_soc_data, },
> 	{ .compatible = "ti,am43", .data = &am4x_soc_data, },
> 	{ .compatible = "ti,dra7", .data = &dra7_soc_data },
> +	{ .compatible = "ti,omap34xx", .data = &omap34xx_soc_data, },
> +	{ .compatible = "ti,omap36xx", .data = &omap36xx_soc_data, },
> +	/* legacy */
> +	{ .compatible = "ti,omap3430", .data = &omap34xx_soc_data, },
> +	{ .compatible = "ti,omap3630", .data = &omap36xx_soc_data, },

Well, I just realized that with the latest DTS changes,

ti,omap34xx and ti,omap36xx are legacy and
ti,omap3430 and ti,omap3630 are now official.

> 	{},
> };
> 
> -- 
> 2.19.1
>