From: Tyrel Datwyler <tyreld@linux.ibm.com>
To: mpe@ellerman.id.au
Cc: benh@kernel.crashing.org, linuxppc-dev@lists.ozlabs.org,
tlfalcon@linux.ibm.com, nathanl@linux.ibm.com,
bhelgaas@google.com, linux-pci@vger.kernel.org,
Tyrel Datwyler <tyreld@linux.ibm.com>
Subject: [PATCH v2 2/9] powerpc/pseries: Fix drc-info mappings of logical cpus to drc-index
Date: Sun, 10 Nov 2019 23:21:29 -0600 [thread overview]
Message-ID: <1573449697-5448-3-git-send-email-tyreld@linux.ibm.com> (raw)
In-Reply-To: <1573449697-5448-1-git-send-email-tyreld@linux.ibm.com>
There are a couple subtle errors in the mapping between cpu-ids and a
cpus associated drc-index when using the new ibm,drc-info property.
The first is that while drc-info may have been a supported firmware
feature at boot it is possible we have migrated to a CEC with older
firmware that doesn't support the ibm,drc-info property. In that case
the device tree would have been updated after migration to remove the
ibm,drc-info property and replace it with the older style ibm,drc-*
properties for types, indexes, names, and power-domains. PAPR even
goes as far as dictating that if we advertise support for drc-info
that we are capable of supporting either property type at runtime.
The second is that the first value of the ibm,drc-info property is
the int encoded count of drc-info entries. As such "value" returned
by of_prop_next_u32() is pointing at that count, and not the first
element of the first drc-info entry as is expected by the
of_read_drc_info_cell() helper.
Fix the first by ignoring DRC-INFO firmware feature and instead
testing directly for ibm,drc-info, and then falling back to the
old style ibm,drc-indexes in the case it doesn't exit.
Fix the second by incrementing value to the next element prior to
parsing drc-info entries.
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
---
arch/powerpc/platforms/pseries/pseries_energy.c | 23 ++++++++++-------------
1 file changed, 10 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/pseries_energy.c b/arch/powerpc/platforms/pseries/pseries_energy.c
index a96874f..09e98d3 100644
--- a/arch/powerpc/platforms/pseries/pseries_energy.c
+++ b/arch/powerpc/platforms/pseries/pseries_energy.c
@@ -36,6 +36,7 @@ static int sysfs_entries;
static u32 cpu_to_drc_index(int cpu)
{
struct device_node *dn = NULL;
+ struct property *info;
int thread_index;
int rc = 1;
u32 ret = 0;
@@ -47,20 +48,18 @@ static u32 cpu_to_drc_index(int cpu)
/* Convert logical cpu number to core number */
thread_index = cpu_core_index_of_thread(cpu);
- if (firmware_has_feature(FW_FEATURE_DRC_INFO)) {
- struct property *info = NULL;
+ info = of_find_property(dn, "ibm,drc-info", NULL);
+ if (info) {
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;
+ else
+ value++;
for (j = 0; j < num_set_entries; j++) {
@@ -110,6 +109,7 @@ static u32 cpu_to_drc_index(int cpu)
static int drc_index_to_cpu(u32 drc_index)
{
struct device_node *dn = NULL;
+ struct property *info;
const int *indexes;
int thread_index = 0, cpu = 0;
int rc = 1;
@@ -117,21 +117,18 @@ static int drc_index_to_cpu(u32 drc_index)
dn = of_find_node_by_path("/cpus");
if (dn == NULL)
goto err;
-
- if (firmware_has_feature(FW_FEATURE_DRC_INFO)) {
- struct property *info = NULL;
+ info = of_find_property(dn, "ibm,drc-info", NULL);
+ if (info) {
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;
+ else
+ value++;
for (j = 0; j < num_set_entries; j++) {
--
2.7.4
next prev parent reply other threads:[~2019-11-11 5:22 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-11 5:21 [PATCH v2 0/9] Fixes and Enablement of ibm,drc-info property Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 1/9] powerpc/pseries: Fix bad drc_index_start value parsing of drc-info entry Tyrel Datwyler
2019-11-14 9:08 ` Michael Ellerman
2019-11-11 5:21 ` Tyrel Datwyler [this message]
2019-11-11 5:21 ` [PATCH v2 3/9] powerpc/pseries: Add cpu DLPAR support for drc-info property Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 4/9] PCI: rpaphp: Fix up pointer to first drc-info entry Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 5/9] PCI: rpaphp: Don't rely on firmware feature to imply drc-info support Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 6/9] PCI: rpaphp: Add drc-info support for hotplug slot registration Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 7/9] PCI: rpaphp: annotate and correctly byte swap DRC properties Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 7/9] PCI: rpaphp: Annotate " Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 8/9] PCI: rpaphp: Correctly match ibm,my-drc-index to drc-name when using drc-info Tyrel Datwyler
2019-11-11 5:21 ` [PATCH v2 9/9] powerpc/pseries: Enable support for ibm,drc-info property Tyrel Datwyler
2019-11-11 19:49 ` [PATCH v2 0/9] Fixes and Enablement of " Bjorn Helgaas
2019-11-12 10:50 ` Michael Ellerman
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