pseries/drc-info: Search DRC properties for CPU indexes

pseries/drc-info: Provide parallel routines to convert between
drc_index and CPU numbers at runtime, using the older device-tree
properties ("ibm,drc-indexes", "ibm,drc-names", "ibm,drc-types"
and "ibm,drc-power-domains"), or the new property "ibm,drc-info".

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h
index 2ab5d73..b04c5ce 100644 (file)
--- a/arch/powerpc/include/asm/prom.h
+++ b/arch/powerpc/include/asm/prom.h
@@ -80,6 +80,21 @@ extern void of_instantiate_rtc(void);
 
 extern int of_get_ibm_chip_id(struct device_node *np);
 
+struct of_drc_info {
+       char *drc_type;
+       char *drc_name_prefix;
+       u32 drc_index_start;
+       u32 drc_name_suffix_start;
+       u32 num_sequential_elems;
+       u32 sequential_inc;
+       u32 drc_power_domain;
+       u32 last_drc_index;
+};
+
+extern int of_read_drc_info_cell(struct property **prop,
+                       const __be32 **curval, struct of_drc_info *data);
+
+
 /*
  * There are two methods for telling firmware what our capabilities are.
  * Newer machines have an "ibm,client-architecture-support" method on the

diff --git a/arch/powerpc/platforms/pseries/of_helpers.c b/arch/powerpc/platforms/pseries/of_helpers.c
index 7e75101..6df192f 100644 (file)
--- a/arch/powerpc/platforms/pseries/of_helpers.c
+++ b/arch/powerpc/platforms/pseries/of_helpers.c
@@ -3,6 +3,7 @@
 #include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/of.h>
+#include <asm/prom.h>
 
 #include "of_helpers.h"
 
@@ -37,3 +38,62 @@ struct device_node *pseries_of_derive_parent(const char *path)
                kfree(parent_path);
        return parent ? parent : ERR_PTR(-EINVAL);
 }
+
+
+/* Helper Routines to convert between drc_index to cpu numbers */
+
+int of_read_drc_info_cell(struct property **prop, const __be32 **curval,
+                       struct of_drc_info *data)
+{
+       const char *p;
+       const __be32 *p2;
+
+       if (!data)
+               return -EINVAL;
+
+       /* Get drc-type:encode-string */
+       p = data->drc_type = (char*) (*curval);
+       p = of_prop_next_string(*prop, p);
+       if (!p)
+               return -EINVAL;
+
+       /* Get drc-name-prefix:encode-string */
+       data->drc_name_prefix = (char *)p;
+       p = of_prop_next_string(*prop, p);
+       if (!p)
+               return -EINVAL;
+
+       /* Get drc-index-start:encode-int */
+       p2 = (const __be32 *)p;
+       p2 = of_prop_next_u32(*prop, p2, &data->drc_index_start);
+       if (!p2)
+               return -EINVAL;
+
+       /* Get drc-name-suffix-start:encode-int */
+       p2 = of_prop_next_u32(*prop, p2, &data->drc_name_suffix_start);
+       if (!p2)
+               return -EINVAL;
+
+       /* Get number-sequential-elements:encode-int */
+       p2 = of_prop_next_u32(*prop, p2, &data->num_sequential_elems);
+       if (!p2)
+               return -EINVAL;
+
+       /* Get sequential-increment:encode-int */
+       p2 = of_prop_next_u32(*prop, p2, &data->sequential_inc);
+       if (!p2)
+               return -EINVAL;
+
+       /* Get drc-power-domain:encode-int */
+       p2 = of_prop_next_u32(*prop, p2, &data->drc_power_domain);
+       if (!p2)
+               return -EINVAL;
+
+       /* Should now know end of current entry */
+       (*curval) = (void *)p2;
+       data->last_drc_index = data->drc_index_start +
+               ((data->num_sequential_elems - 1) * data->sequential_inc);
+
+       return 0;
+}
+EXPORT_SYMBOL(of_read_drc_info_cell);

diff --git a/arch/powerpc/platforms/pseries/pseries_energy.c b/arch/powerpc/platforms/pseries/pseries_energy.c
index 35c891a..6ed2212 100644 (file)
--- a/arch/powerpc/platforms/pseries/pseries_energy.c
+++ b/arch/powerpc/platforms/pseries/pseries_energy.c
@@ -22,6 +22,7 @@
 #include <asm/page.h>
 #include <asm/hvcall.h>
 #include <asm/firmware.h>
+#include <asm/prom.h>
 
 
 #define MODULE_VERS "1.0"
@@ -38,26 +39,58 @@ static int sysfs_entries;
 static u32 cpu_to_drc_index(int cpu)
 {
        struct device_node *dn = NULL;
-       const int *indexes;
-       int i;
+       int thread_index;
        int rc = 1;
        u32 ret = 0;
 
        dn = of_find_node_by_path("/cpus");
        if (dn == NULL)
                goto err;
-       indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
-       if (indexes == NULL)
-               goto err_of_node_put;
+
        /* Convert logical cpu number to core number */
-       i = cpu_core_index_of_thread(cpu);
-       /*
-        * The first element indexes[0] is the number of drc_indexes
-        * returned in the list.  Hence i+1 will get the drc_index
-        * corresponding to core number i.
-        */
-       WARN_ON(i > indexes[0]);
-       ret = indexes[i + 1];
+       thread_index = cpu_core_index_of_thread(cpu);
+
+       if (firmware_has_feature(FW_FEATURE_DRC_INFO)) {
+               struct property *info = NULL;
+               struct of_drc_info drc;
+               int j;
+               u32 num_set_entries;
+               const __be32 *value;
+
+               info = of_find_property(dn, "ibm,drc-info", NULL);
+               if (info == NULL)
+                       goto err_of_node_put;
+
+               value = of_prop_next_u32(info, NULL, &num_set_entries);
+               if (!value)
+                       goto err_of_node_put;
+
+               for (j = 0; j < num_set_entries; j++) {
+
+                       of_read_drc_info_cell(&info, &value, &drc);
+                       if (strncmp(drc.drc_type, "CPU", 3))
+                               goto err;
+
+                       if (thread_index < drc.last_drc_index)
+                               break;
+               }
+
+               ret = drc.drc_index_start + (thread_index * drc.sequential_inc);
+       } else {
+               const __be32 *indexes;
+
+               indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
+               if (indexes == NULL)
+                       goto err_of_node_put;
+
+               /*
+                * The first element indexes[0] is the number of drc_indexes
+                * returned in the list.  Hence thread_index+1 will get the
+                * drc_index corresponding to core number thread_index.
+                */
+               ret = indexes[thread_index + 1];
+       }
+
        rc = 0;
 
 err_of_node_put:
@@ -72,34 +105,71 @@ static int drc_index_to_cpu(u32 drc_index)
 {
        struct device_node *dn = NULL;
        const int *indexes;
-       int i, cpu = 0;
+       int thread_index = 0, cpu = 0;
        int rc = 1;
 
        dn = of_find_node_by_path("/cpus");
        if (dn == NULL)
                goto err;
-       indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
-       if (indexes == NULL)
-               goto err_of_node_put;
-       /*
-        * First element in the array is the number of drc_indexes
-        * returned.  Search through the list to find the matching
-        * drc_index and get the core number
-        */
-       for (i = 0; i < indexes[0]; i++) {
-               if (indexes[i + 1] == drc_index)
+
+       if (firmware_has_feature(FW_FEATURE_DRC_INFO)) {
+               struct property *info = NULL;
+               struct of_drc_info drc;
+               int j;
+               u32 num_set_entries;
+               const __be32 *value;
+
+               info = of_find_property(dn, "ibm,drc-info", NULL);
+               if (info == NULL)
+                       goto err_of_node_put;
+
+               value = of_prop_next_u32(info, NULL, &num_set_entries);
+               if (!value)
+                       goto err_of_node_put;
+
+               for (j = 0; j < num_set_entries; j++) {
+
+                       of_read_drc_info_cell(&info, &value, &drc);
+                       if (strncmp(drc.drc_type, "CPU", 3))
+                               goto err;
+
+                       if (drc_index > drc.last_drc_index) {
+                               cpu += drc.num_sequential_elems;
+                               continue;
+                       }
+                       cpu += ((drc_index - drc.drc_index_start) /
+                               drc.sequential_inc);
+
+                       thread_index = cpu_first_thread_of_core(cpu);
+                       rc = 0;
                        break;
+               }
+       } else {
+               unsigned long int i;
+
+               indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
+               if (indexes == NULL)
+                       goto err_of_node_put;
+               /*
+                * First element in the array is the number of drc_indexes
+                * returned.  Search through the list to find the matching
+                * drc_index and get the core number
+                */
+               for (i = 0; i < indexes[0]; i++) {
+                       if (indexes[i + 1] == drc_index)
+                               break;
+               }
+               /* Convert core number to logical cpu number */
+               thread_index = cpu_first_thread_of_core(i);
+               rc = 0;
        }
-       /* Convert core number to logical cpu number */
-       cpu = cpu_first_thread_of_core(i);
-       rc = 0;
 
 err_of_node_put:
        of_node_put(dn);
 err:
        if (rc)
                printk(KERN_WARNING "drc_index_to_cpu(%d) failed", drc_index);
-       return cpu;
+       return thread_index;
 }
 
 /*