Re: [RESEND PATCH v2 2/2] cpufreq: qcom-nvmem: add support for IPQ8064

From: Dmitry Baryshkov
Date: Thu Jun 01 2023 - 11:09:18 EST


On 31/05/2023 04:36, Christian Marangi wrote:
On Wed, May 31, 2023 at 05:03:01AM +0300, Dmitry Baryshkov wrote:
On 30/05/2023 19:58, Robert Marko wrote:
From: Christian Marangi <ansuelsmth@xxxxxxxxx>

IPQ8064 comes in 3 families:
* IPQ8062 up to 1.0GHz
* IPQ8064/IPQ8066/IPQ8068 up to 1.4GHz
* IPQ8065/IPQ8069 up to 1.7Ghz

So, in order to be able to share one OPP table, add support for
IPQ8064 family based of SMEM SoC ID-s as speedbin fuse is always 0 on
IPQ8064.

Bit are set with the following logic:
* IPQ8062 BIT 0
* IPQ8064/IPQ8066/IPQ8068 BIT 1
* IPQ8065/IPQ8069 BIT 2

speed is never fused, only psv values are fused.
Set speed to the versions to permit a unified opp table following
this named opp:

opp-microvolt-speed<SPEED_VALUE>-pvs<PSV_VALUE>-v0

Example:
- for ipq8062 psv2
opp-microvolt-speed0-pvs2-v0 = < 925000 878750 971250>
- for ipq8064 psv2
opp-microvolt-speed2-pvs2-v0 = <925000 878750 971250>;
- for ipq8065 psv2
opp-microvolt-speed4-pvs2-v0 = <950000 902500 997500>;

Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
Signed-off-by: Robert Marko <robimarko@xxxxxxxxx>
---
drivers/cpufreq/qcom-cpufreq-nvmem.c | 73 +++++++++++++++++++++++++++-
1 file changed, 72 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
index ce444b5962f2..c644138680ba 100644
--- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
+++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
@@ -34,6 +34,10 @@
#define IPQ8074_HAWKEYE_VERSION BIT(0)
#define IPQ8074_ACORN_VERSION BIT(1)
+#define IPQ8062_VERSION BIT(0)
+#define IPQ8064_VERSION BIT(1)
+#define IPQ8065_VERSION BIT(2)

I think it would be more logical to change these defines to consecutive enum
instead of BIT(n) values. Another (and better in my opinion) option is to
drop versions completely (and remove speedN from the opp names) and to have
per-SoC tables in per-SoC dtsi files. There are already separate
ipq8064.dtsi, ipq8062.dtsi and ipq8065.dtsi files. It makes little sense to
overcomplicate the OPP tables.


That is what was used downstream but it was also wrong and against the
normal implementation of this driver itself.

OPP have opp-supported-hw just for the task with the principle of
declaring a single table in dtsi and automatically select the right one.

Using the implementation downstream (opp table in each dtsi) is actually
worse as ipq8065 have 1.4ghz and not 1.2ghz and that can correctly be
handled with opp-supported-hw (and this change) or using delete-property
in dtsi (that I don't really like and it's ugly)

Also this implementation would match what is currently secribed for the
use of OPP in the documentation.

Hope you can understand the reason of this change, the intention is to
clear and trying to use standard OPP stuff instead of hacks in the DTS.

I'm fine with the opp-supported-hw part (I forgot that it is used by default with the help of drv->versions). I do not like the idea of encoding the same value into the -speedN part. If it is not needed, it's better be dropped than using a semi-dummy value there.

So, I'd suggest to define an enum, use BIT(enum_value) for drv->versions and drop the speed%d part.

Also, while we are at it, could you please define a schema for your opp extensions? An example would make it easier to understand the bindings (and will also provide a reference for possible other implementers).


+
struct qcom_cpufreq_drv;
struct qcom_cpufreq_match_data {
@@ -207,6 +211,69 @@ static int qcom_cpufreq_krait_name_version(struct device *cpu_dev,
return ret;
}
+static int qcom_cpufreq_ipq8064_name_version(struct device *cpu_dev,
+ struct nvmem_cell *speedbin_nvmem,
+ char **pvs_name,
+ struct qcom_cpufreq_drv *drv)
+{
+ int speed = 0, pvs = 0, pvs_ver = 0;
+ int msm_id, ret = 0;
+ u8 *speedbin;
+ size_t len;
+
+ speedbin = nvmem_cell_read(speedbin_nvmem, &len);
+
+ if (IS_ERR(speedbin))
+ return PTR_ERR(speedbin);
+
+ switch (len) {
+ case 4:
+ get_krait_bin_format_a(cpu_dev, &speed, &pvs, &pvs_ver,
+ speedbin);
+ break;
+ default:
+ dev_err(cpu_dev, "Unable to read nvmem data. Defaulting to 0!\n");
+ ret = -ENODEV;
+ goto len_error;
+ }
+
+ ret = qcom_smem_get_soc_id(&msm_id);
+ if (ret)
+ return ret;
+
+ switch (msm_id) {
+ case QCOM_ID_IPQ8062:
+ drv->versions = IPQ8062_VERSION;
+ break;
+ case QCOM_ID_IPQ8064:
+ case QCOM_ID_IPQ8066:
+ case QCOM_ID_IPQ8068:
+ drv->versions = IPQ8064_VERSION;
+ break;
+ case QCOM_ID_IPQ8065:
+ case QCOM_ID_IPQ8069:
+ drv->versions = IPQ8065_VERSION;
+ break;
+ default:
+ dev_err(cpu_dev,
+ "SoC ID %u is not part of IPQ8064 family, limiting to 1.0GHz!\n",
+ msm_id);
+ drv->versions = IPQ8062_VERSION;
+ break;
+ }
+
+ /*
+ * IPQ8064 speed is never fused. Only psv values are fused.
+ * Set speed to the versions to permit a unified opp table.
+ */
+ snprintf(*pvs_name, sizeof("speedXX-pvsXX-vXX"), "speed%d-pvs%d-v%d",
+ drv->versions, pvs, pvs_ver);
+
+len_error:
+ kfree(speedbin);
+ return ret;
+}
+
static int qcom_cpufreq_ipq8074_name_version(struct device *cpu_dev,
struct nvmem_cell *speedbin_nvmem,
char **pvs_name,
@@ -256,6 +323,10 @@ static const struct qcom_cpufreq_match_data match_data_qcs404 = {
.genpd_names = qcs404_genpd_names,
};
+static const struct qcom_cpufreq_match_data match_data_ipq8064 = {
+ .get_version = qcom_cpufreq_ipq8064_name_version,
+};
+
static const struct qcom_cpufreq_match_data match_data_ipq8074 = {
.get_version = qcom_cpufreq_ipq8074_name_version,
};
@@ -404,7 +475,7 @@ static const struct of_device_id qcom_cpufreq_match_list[] __initconst = {
{ .compatible = "qcom,apq8096", .data = &match_data_kryo },
{ .compatible = "qcom,msm8996", .data = &match_data_kryo },
{ .compatible = "qcom,qcs404", .data = &match_data_qcs404 },
- { .compatible = "qcom,ipq8064", .data = &match_data_krait },
+ { .compatible = "qcom,ipq8064", .data = &match_data_ipq8064 },
{ .compatible = "qcom,ipq8074", .data = &match_data_ipq8074 },
{ .compatible = "qcom,apq8064", .data = &match_data_krait },
{ .compatible = "qcom,msm8974", .data = &match_data_krait },

--
With best wishes
Dmitry



--
With best wishes
Dmitry