perf/arm-cmn: Ensure dtm_idx is big enough

While CMN_MAX_DIMENSION was bumped to 12 for CMN-650, that only supports
up to a 10x10 mesh, so bumping dtm_idx to 256 bits at the time worked
out OK in practice. However CMN-700 did finally support up to 144 XPs,
and thus needs a worst-case 288 bits of dtm_idx for an aggregated XP
event on a maxed-out config. Oops.

Fixes: 23760a014417 ("perf/arm-cmn: Add CMN-700 support")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/e771b358526a0d7fc06efee2c3a2fdc0c9f51d44.1725296395.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index 4e2338afe66944d869f2b9bbd5b3fc5a612da7e1..48863b31ccfb12c400f770758215a85d228306cf 100644 (file)
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -35,6 +35,9 @@
 #define CMN_MAX_XPS                    (CMN_MAX_DIMENSION * CMN_MAX_DIMENSION)
 #define CMN_MAX_DTMS                   (CMN_MAX_XPS + (CMN_MAX_DIMENSION - 1) * 4)
 
+/* Currently XPs are the node type we can have most of; others top out at 128 */
+#define CMN_MAX_NODES_PER_EVENT                CMN_MAX_XPS
+
 /* The CFG node has various info besides the discovery tree */
 #define CMN_CFGM_PERIPH_ID_01          0x0008
 #define CMN_CFGM_PID0_PART_0           GENMASK_ULL(7, 0)
@@ -564,7 +567,7 @@ static void arm_cmn_debugfs_init(struct arm_cmn *cmn, int id) {}
 
 struct arm_cmn_hw_event {
        struct arm_cmn_node *dn;
-       u64 dtm_idx[4];
+       u64 dtm_idx[DIV_ROUND_UP(CMN_MAX_NODES_PER_EVENT * 2, 64)];
        s8 dtc_idx[CMN_MAX_DTCS];
        u8 num_dns;
        u8 dtm_offset;