On 05/22/2018 11:37 AM, Michael Bringmann wrote:
> This patch extends the use of a common parse function for the
> ibm,drc-info property that can be modified by a callback function
> to the hotplug device processing.  Candidate code is replaced by
> a call to the parser including a pointer to a local context-specific
> functions, and local data.
> 
> In addition, several more opportunities to compress and reuse
> common code between the old and new property parsers were applied.
> 
> Finally, a bug with the registration of slots was observed on some
> systems, and the code was rewritten to prevent its reoccurrence.
> 
> Signed-off-by: Michael Bringmann <m...@linux.vnet.ibm.com>
> Fixes: 3f38000eda48 ("powerpc/firmware: Add definitions for new drc-info 
> firmwar
> e feature" -- end of patch series applied to powerpc next)
> ---
> Changes in V4:
>   -- Update code to account for latest kernel checkins.
>   -- Fix bug searching for virtual device slots.
>   -- Rebased to 4.17-rc5 kernel
>   -- Patch cleanup
> ---
>  drivers/pci/hotplug/rpaphp_core.c |  181 
> ++++++++++++++++++++++++++-----------
>  1 file changed, 126 insertions(+), 55 deletions(-)
> 
> diff --git a/drivers/pci/hotplug/rpaphp_core.c 
> b/drivers/pci/hotplug/rpaphp_core.c
> index 435c1a0..dc4ec68 100644
> --- a/drivers/pci/hotplug/rpaphp_core.c
> +++ b/drivers/pci/hotplug/rpaphp_core.c
> @@ -222,47 +222,51 @@ static int rpaphp_check_drc_props_v1(struct device_node 
> *dn, char *drc_name,
>       return -EINVAL;
>  }
> 
> -static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
> -                             char *drc_type, unsigned int my_index)
> +struct check_drc_props_v2_struct {
> +     char *drc_name;
> +     char *drc_type;
> +     unsigned int my_index;
> +};
> +
> +static int check_drc_props_v2_cb(struct of_drc_info *drc, void *idata,
> +                             void *not_used, int *ret_code)
>  {
> -     struct property *info;
> -     unsigned int entries;
> -     struct of_drc_info drc;
> -     const __be32 *value;
> +     struct check_drc_props_v2_struct *cdata = idata;
>       char cell_drc_name[MAX_DRC_NAME_LEN];
> -     int j, fndit;
> 
> -     info = of_find_property(dn->parent, "ibm,drc-info", NULL);
> -     if (info == NULL)
> -             return -EINVAL;
> +     (*ret_code) = -EINVAL;
> 
> -     value = info->value;
> -     entries = of_read_number(value++, 1);
> -
> -     for (j = 0; j < entries; j++) {
> -             of_read_drc_info_cell(&info, &value, &drc);
> -
> -             /* Should now know end of current entry */
> -
> -             if (my_index > drc.last_drc_index)
> -                     continue;
> +     if (cdata->my_index > drc->last_drc_index)
> +             return 0;
> 
> -             fndit = 1;
> -             break;
> +     /* Found drc_index.  Now match the rest. */
> +     sprintf(cell_drc_name, "%s%d", drc->drc_name_prefix,
> +             cdata->my_index - drc->drc_index_start +
> +             drc->drc_name_suffix_start);
> +
> +     if (((cdata->drc_name == NULL) ||
> +          (cdata->drc_name && !strcmp(cdata->drc_name, cell_drc_name))) &&
> +         ((cdata->drc_type == NULL) ||
> +          (cdata->drc_type && !strcmp(cdata->drc_type, drc->drc_type)))) {
> +             (*ret_code) = 0;
> +             return 1;
>       }
> -     /* Found it */
> 
> -     if (fndit)
> -             sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix, 
> -                     my_index);
> +     return 0;
> +}
> 
> -     if (((drc_name == NULL) ||
> -          (drc_name && !strcmp(drc_name, cell_drc_name))) &&
> -         ((drc_type == NULL) ||
> -          (drc_type && !strcmp(drc_type, drc.drc_type))))
> -             return 0;
> +static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
> +                             char *drc_type, unsigned int my_index)
> +{
> +     struct device_node *root = dn;
> +     struct check_drc_props_v2_struct cdata = {
> +             drc_name, drc_type, be32_to_cpu(my_index) };
> 
> -     return -EINVAL;
> +     if (!drc_type || (drc_type && strcmp(drc_type, "SLOT")))
> +             root = dn->parent;
> +
> +     return drc_info_parser(root, check_drc_props_v2_cb,
> +                             drc_type, &cdata);
>  }
> 
>  int rpaphp_check_drc_props(struct device_node *dn, char *drc_name,
> @@ -285,7 +289,6 @@ int rpaphp_check_drc_props(struct device_node *dn, char 
> *drc_name,
>  }
>  EXPORT_SYMBOL_GPL(rpaphp_check_drc_props);
> 
> -
>  static int is_php_type(char *drc_type)
>  {
>       unsigned long value;
> @@ -345,17 +348,41 @@ static int is_php_dn(struct device_node *dn, const int 
> **indexes,
>   *
>   * To remove a slot, it suffices to call rpaphp_deregister_slot().
>   */
> -int rpaphp_add_slot(struct device_node *dn)
> +
> +static int rpaphp_add_slot_common(struct device_node *dn,
> +                     u32 drc_index, char *drc_name, char *drc_type,
> +                     u32 drc_power_domain)
>  {
>       struct slot *slot;
>       int retval = 0;
> -     int i;
> +
> +     slot = alloc_slot_struct(dn, drc_index, drc_name, drc_power_domain);
> +     if (!slot)
> +             return -ENOMEM;
> +
> +     slot->type = simple_strtoul(drc_type, NULL, 10);
> +     if (retval)
> +             return -EINVAL;
> +
> +     dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
> +             drc_index, drc_name, drc_type);
> +
> +     retval = rpaphp_enable_slot(slot);
> +     if (!retval)
> +             retval = rpaphp_register_slot(slot);
> +
> +     if (retval)
> +             dealloc_slot_struct(slot);
> +
> +     return retval;
> +}
> +
> +static int rpaphp_add_slot_v1(struct device_node *dn)
> +{
> +     int i, retval = 0;
>       const int *indexes, *names, *types, *power_domains;
>       char *name, *type;
> 
> -     if (!dn->name || strcmp(dn->name, "pci"))
> -             return 0;
> -
>       /* If this is not a hotplug slot, return without doing anything. */
>       if (!is_php_dn(dn, &indexes, &names, &types, &power_domains))
>               return 0;
> @@ -366,25 +393,12 @@ int rpaphp_add_slot(struct device_node *dn)
>       name = (char *) &names[1];
>       type = (char *) &types[1];
>       for (i = 0; i < be32_to_cpu(indexes[0]); i++) {
> -             int index;
> -
> -             index = be32_to_cpu(indexes[i + 1]);
> -             slot = alloc_slot_struct(dn, index, name,
> -                                      be32_to_cpu(power_domains[i + 1]));
> -             if (!slot)
> -                     return -ENOMEM;
> -
> -             slot->type = simple_strtoul(type, NULL, 10);
> 
> -             dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
> -                             index, name, type);
> -
> -             retval = rpaphp_enable_slot(slot);
> +             retval = rpaphp_add_slot_common(dn,
> +                             be32_to_cpu(indexes[i + 1]), name, type,
> +                             be32_to_cpu(power_domains[i + 1]));
>               if (!retval)
> -                     retval = rpaphp_register_slot(slot);
> -
> -             if (retval)
> -                     dealloc_slot_struct(slot);
> +                     return retval;
> 
>               name += strlen(name) + 1;
>               type += strlen(type) + 1;
> @@ -394,6 +408,63 @@ int rpaphp_add_slot(struct device_node *dn)
>       /* XXX FIXME: reports a failure only if last entry in loop failed */
>       return retval;
>  }
> +
> +struct rpaphp_add_slot_v2_struct {
> +     struct device_node *dn;
> +};
> +
> +static int rpaphp_add_slot_v2_cb(struct of_drc_info *drc, void *idata,
> +                             void *not_used, int *ret_code)
> +{
> +     struct rpaphp_add_slot_v2_struct *cdata = idata;
> +     u32 drc_index;
> +     char drc_name[MAX_DRC_NAME_LEN];
> +     int i, retval;
> +
> +     (*ret_code) = -EINVAL;
> +
> +     if (!is_php_type((char *) drc->drc_type)) {
> +             (*ret_code) = 0;
> +             return 1;
> +     }
> +
> +     for (i = 0, drc_index = drc->drc_index_start;
> +             i < drc->num_sequential_elems; i++, drc_index++) {
> +
> +             sprintf(drc_name, "%s%d", drc->drc_name_prefix,
> +                     drc_index - drc->drc_index_start +
> +                     drc->drc_name_suffix_start);
> +
> +             retval = rpaphp_add_slot_common(cdata->dn,
> +                             drc_index, drc_name, drc->drc_type,
> +                             drc->drc_power_domain);
> +             if (!retval) {
> +                     (*ret_code) = retval;
> +                     return 1;
> +             }
> +     }

I may be reading this loop wrong, but it appears that it will add all drc 
indexes
for all drc_info entries to the specified device node, minus drc-types that 
don't match.

-Nathan

> +
> +     (*ret_code) = retval;
> +     return 0;
> +}
> +
> +static int rpaphp_add_slot_v2(struct device_node *dn)
> +{
> +     struct rpaphp_add_slot_v2_struct cdata = { dn };
> +
> +     return drc_info_parser(dn, rpaphp_add_slot_v2_cb, NULL, &cdata);
> +}
> +
> +int rpaphp_add_slot(struct device_node *dn)
> +{
> +     if (!dn->name || strcmp(dn->name, "pci"))
> +             return 0;
> +
> +     if (firmware_has_feature(FW_FEATURE_DRC_INFO))
> +             return rpaphp_add_slot_v2(dn);
> +     else
> +             return rpaphp_add_slot_v1(dn);
> +}
>  EXPORT_SYMBOL_GPL(rpaphp_add_slot);
> 
>  static void __exit cleanup_slots(void)
> 

Reply via email to