thermal: intel: int340x: Capability to map user space to firmware values

To ensure compatibility between user inputs and firmware requirements,
a conversion mechanism is necessary for certain attributes. For instance,
on some platforms, the DLVR frequency must be translated into a predefined
index before being communicated to the firmware. On Lunar Lake platform:
RFI_FREQ_SELECT and RFI_FREQ:
Index 0 corresponds to a DLVR frequency of 2227.2 MHz
Index 1 corresponds to a DLVR frequency of 2140 MHz

Introduce a feature that enables the conversion of values between user
space inputs and firmware-accepted formats. This feature would also
facilitate the reverse process, converting firmware values back into user
friendly display values.

To support this functionality, a model-specific mapping table will be
utilized. When available, this table will provide the necessary
translations between user space values and firmware values, ensuring
seamless communication and accurate settings.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://patch.msgid.link/20240619124600.491168-3-srinivas.pandruvada@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c
index e56db75a94fb78f07aa0d46c82ddac8c88711f82..c9c77bca20145b5d68918e123efea27abc567885 100644 (file)
--- a/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c
@@ -19,6 +19,12 @@ struct mmio_reg {
        u16 shift;
 };
 
+struct mapping_table {
+       const char *attr_name;
+       const u32 value;
+       const char *mapped_str;
+};
+
 /* These will represent sysfs attribute names */
 static const char * const fivr_strings[] = {
        "vco_ref_code_lo",
@@ -62,6 +68,59 @@ static const struct mmio_reg dlvr_mmio_regs[] = {
        { 1, 0x15A10, 1, 0x1, 16}, /* dlvr_pll_busy */
 };
 
+static int match_mapping_table(const struct mapping_table *table, const char *attr_name,
+                              bool match_int_value, const u32 value, const char *value_str,
+                              char **result_str, u32 *result_int)
+{
+       bool attr_matched = false;
+       int i = 0;
+
+       if (!table)
+               return -EOPNOTSUPP;
+
+       while (table[i].attr_name) {
+               if (strncmp(table[i].attr_name, attr_name, strlen(attr_name)))
+                       goto match_next;
+
+               attr_matched = true;
+
+               if (match_int_value) {
+                       if (table[i].value != value)
+                               goto match_next;
+
+                       *result_str = (char *)table[i].mapped_str;
+                       return 0;
+               }
+
+               if (strncmp(table[i].mapped_str, value_str, strlen(table[i].mapped_str)))
+                       goto match_next;
+
+               *result_int = table[i].value;
+
+               return 0;
+match_next:
+               i++;
+       }
+
+       /* If attribute name is matched, then the user space value is invalid */
+       if (attr_matched)
+               return -EINVAL;
+
+       return -EOPNOTSUPP;
+}
+
+static int get_mapped_string(const struct mapping_table *table, const char *attr_name,
+                            u32 value, char **result)
+{
+       return match_mapping_table(table, attr_name, true, value, NULL, result, NULL);
+}
+
+static int get_mapped_value(const struct mapping_table *table, const char *attr_name,
+                           const char *value, unsigned int *result)
+{
+       return match_mapping_table(table, attr_name, false, 0, value, NULL, result);
+}
+
 /* These will represent sysfs attribute names */
 static const char * const dvfs_strings[] = {
        "rfi_restriction_run_busy",
@@ -93,12 +152,14 @@ static ssize_t suffix##_show(struct device *dev,\
                              struct device_attribute *attr,\
                              char *buf)\
 {\
+       const struct mapping_table *mapping = NULL;\
        struct proc_thermal_device *proc_priv;\
        struct pci_dev *pdev = to_pci_dev(dev);\
        const struct mmio_reg *mmio_regs;\
        const char **match_strs;\
+       int ret, err;\
        u32 reg_val;\
-       int ret;\
+       char *str;\
 \
        proc_priv = pci_get_drvdata(pdev);\
        if (table == 1) {\
@@ -116,7 +177,12 @@ static ssize_t suffix##_show(struct device *dev,\
                return ret;\
        reg_val = readl((void __iomem *) (proc_priv->mmio_base + mmio_regs[ret].offset));\
        ret = (reg_val >> mmio_regs[ret].shift) & mmio_regs[ret].mask;\
-       return sprintf(buf, "%u\n", ret);\
+       err = get_mapped_string(mapping, attr->attr.name, ret, &str);\
+       if (!err)\
+               return sprintf(buf, "%s\n", str);\
+       if (err == -EOPNOTSUPP)\
+               return sprintf(buf, "%u\n", ret);\
+       return err;\
 }
 
 #define RFIM_STORE(suffix, table)\
@@ -124,6 +190,7 @@ static ssize_t suffix##_store(struct device *dev,\
                               struct device_attribute *attr,\
                               const char *buf, size_t count)\
 {\
+       const struct mapping_table *mapping = NULL;\
        struct proc_thermal_device *proc_priv;\
        struct pci_dev *pdev = to_pci_dev(dev);\
        unsigned int input;\
@@ -150,9 +217,14 @@ static ssize_t suffix##_store(struct device *dev,\
                return ret;\
        if (mmio_regs[ret].read_only)\
                return -EPERM;\
-       err = kstrtouint(buf, 10, &input);\
-       if (err)\
+       err = get_mapped_value(mapping, attr->attr.name, buf, &input);\
+       if (err == -EINVAL)\
                return err;\
+       if (err == -EOPNOTSUPP) {\
+               err = kstrtouint(buf, 10, &input);\
+               if (err)\
+                       return err;\
+       } \
        mask = GENMASK(mmio_regs[ret].shift + mmio_regs[ret].bits - 1, mmio_regs[ret].shift);\
        reg_val = readl((void __iomem *) (proc_priv->mmio_base + mmio_regs[ret].offset));\
        reg_val &= ~mask;\