On 11/5/19 8:55 AM, Thomas Falcon wrote:
>
> On 11/5/19 9:24 AM, Tyrel Datwyler wrote:
>> From: Tyrel Datwyler <tyr...@linux.vnet.ibm.com>
>>
>> Older firmwares provided information about Dynamic Reconfig
>> Connectors (DRC) through several device tree properties, namely
>> ibm,drc-types, ibm,drc-indexes, ibm,drc-names, and
>> ibm,drc-power-domains. New firmwares have the ability to present this
>> same information in a much condensed format through a device tree
>> property called ibm,drc-info.
>>
>> The existing cpu DLPAR hotplug code only understands the older DRC
>> property format when validating the drc-index of a cpu during a
>> hotplug add. This updates those code paths to use the ibm,drc-info
>> property, when present, instead for validation.
>>
>> Signed-off-by: Tyrel Datwyler <tyr...@linux.ibm.com>
>> ---
>> arch/powerpc/platforms/pseries/hotplug-cpu.c | 101
>> ++++++++++++++++++++++-----
>> 1 file changed, 85 insertions(+), 16 deletions(-)
>>
>> diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c
>> b/arch/powerpc/platforms/pseries/hotplug-cpu.c
>> index bbda646..9ba006c 100644
>> --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
>> +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
>> @@ -407,17 +407,58 @@ static bool dlpar_cpu_exists(struct device_node
>> *parent,
>> u32 drc_index)
>> return found;
>> }
>>
>> +static bool drc_info_valid_index(struct device_node *parent, u32 drc_index)
>> +{
>> + struct property *info;
>> + struct of_drc_info drc;
>> + const __be32 *value;
>> + int count, i, j;
>> +
>> + info = of_find_property(parent, "ibm,drc-info", NULL);
>> + if (!info)
>> + return false;
>> +
>> + value = of_prop_next_u32(info, NULL, &count);
>> +
>> + /* First value of ibm,drc-info is number of drc-info records */
>> + if (value)
>> + value++;
>> + else
>> + return false;
>> +
>> + for (i = 0; i < count; i++) {
>> + if (of_read_drc_info_cell(&info, &value, &drc))
>> + return false;
>> +
>> + if (strncmp(drc.drc_type, "CPU", 3))
>> + break;
>> +
>> + if (drc_index > drc.last_drc_index)
>> + continue;
>> +
>> + for (j = 0; j < drc.num_sequential_elems; j++)
>> + if (drc_index == (drc.drc_index_start + (drc.sequential_inc *
>> j)))
>> + return true;
>> + }
>> +
>> + return false;
>> +}
>> +
>> static bool valid_cpu_drc_index(struct device_node *parent, u32 drc_index)
>> {
>> bool found = false;
>> int rc, index;
>>
>> - index = 0;
>> + if (of_find_property(parent, "ibm,drc-info", NULL))
>> + return drc_info_valid_index(parent, drc_index);
>> +
>> + index = 1;
>
> Hi, this change was confusing to me until I continued reading the patch and
> saw
> the comment below regarding the first element of the ibm,drc-info property.
> Would it be good to have a similar comment here too?
>
Yeah, clearly wouldn't hurt. Probably should split it out into a separate fix
prior to this patch.
>
>> while (!found) {
>> u32 drc;
>>
>> rc = of_property_read_u32_index(parent, "ibm,drc-indexes",
>> index++, &drc);
>> +
>
> Another nitpick but this could be cleaned up.
Yep, noticed the newline addition after I'd already sent it out.
-Tyrel
>
> Thanks,
>
> Tom
>
>
>> if (rc)
>> break;
>>
>> @@ -720,8 +761,11 @@ static int dlpar_cpu_remove_by_count(u32 cpus_to_remove)
>> static int find_dlpar_cpus_to_add(u32 *cpu_drcs, u32 cpus_to_add)
>> {
>> struct device_node *parent;
>> + struct property *info;
>> int cpus_found = 0;
>> int index, rc;
>> + int i, j;
>> + u32 drc_index;
>>
>> parent = of_find_node_by_path("/cpus");
>> if (!parent) {
>> @@ -730,24 +774,49 @@ static int find_dlpar_cpus_to_add(u32 *cpu_drcs, u32
>> cpus_to_add)
>> return -1;
>> }
>>
>> - /* Search the ibm,drc-indexes array for possible CPU drcs to
>> - * add. Note that the format of the ibm,drc-indexes array is
>> - * the number of entries in the array followed by the array
>> - * of drc values so we start looking at index = 1.
>> - */
>> - index = 1;
>> - while (cpus_found < cpus_to_add) {
>> - u32 drc;
>> + info = of_find_property(parent, "ibm,drc-info", NULL);
>> + if (info) {
>> + struct of_drc_info drc;
>> + const __be32 *value;
>> + int count;
>>
>> - rc = of_property_read_u32_index(parent, "ibm,drc-indexes",
>> - index++, &drc);
>> - if (rc)
>> - break;
>> + value = of_prop_next_u32(info, NULL, &count);
>> + if (value)
>> + value++;
>>
>> - if (dlpar_cpu_exists(parent, drc))
>> - continue;
>> + for (i = 0; i < count; i++) {
>> + of_read_drc_info_cell(&info, &value, &drc);
>> + if (strncmp(drc.drc_type, "CPU", 3))
>> + break;
>> +
>> + for (j = 0; j < drc.num_sequential_elems && cpus_found <
>> cpus_to_add; j++) {
>> + drc_index = drc.drc_index_start + (drc.sequential_inc * j);
>> +
>> + if (dlpar_cpu_exists(parent, drc_index))
>> + continue;
>> +
>> + cpu_drcs[cpus_found++] = drc_index;
>> + }
>> + }
>> + } else {
>> + /* Search the ibm,drc-indexes array for possible CPU drcs to
>> + * add. Note that the format of the ibm,drc-indexes array is
>> + * the number of entries in the array followed by the array
>> + * of drc values so we start looking at index = 1.
>> + */
>> + index = 1;
>> + while (cpus_found < cpus_to_add) {
>> + rc = of_property_read_u32_index(parent, "ibm,drc-indexes",
>> + index++, &drc_index);
>> +
>> + if (rc)
>> + break;
>>
>> - cpu_drcs[cpus_found++] = drc;
>> + if (dlpar_cpu_exists(parent, drc_index))
>> + continue;
>> +
>> + cpu_drcs[cpus_found++] = drc_index;
>> + }
>> }
>>
>> of_node_put(parent);
