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| author | Benoît Monin <benoit.monin@bootlin.com> | 2025-11-07 11:46:57 +0100 |
|---|---|---|
| committer | Anup Patel <anup@brainfault.org> | 2025-11-10 13:41:53 +0530 |
| commit | 5de1d3240f9163de95bc6803fb4100a77d65ab6b (patch) | |
| tree | 0bac4da1c4d8e8c6a8f94a8c3c72eb5bb1a68226 /lib/utils/timer/fdt_timer_mtimer.c | |
| parent | 38a6106b1099646f25657bba53cefb80886721a7 (diff) | |
| download | opensbi-5de1d3240f9163de95bc6803fb4100a77d65ab6b.tar.gz opensbi-5de1d3240f9163de95bc6803fb4100a77d65ab6b.tar.bz2 opensbi-5de1d3240f9163de95bc6803fb4100a77d65ab6b.zip | |
lib: utils/timer: mtimer: Select the reference mtimer from a DT property
The current selection of the reference MTIMER may fail in some setup.
In a multi-cluster configuration, there is one MTIMER per cluster, each
associated with the HARTS of the cluster. So we do not have a MTIMER
with no associated HARTs to use as our reference.
To be able to select a reference MTIMER in that case, look up an optional
device tree property named "riscv,reference-mtimer" that indicate which
MTIMER is the reference.
Signed-off-by: Benoît Monin <benoit.monin@bootlin.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20251107-p8700-aclint-v3-1-93eabb17d54e@bootlin.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Diffstat (limited to 'lib/utils/timer/fdt_timer_mtimer.c')
| -rw-r--r-- | lib/utils/timer/fdt_timer_mtimer.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/lib/utils/timer/fdt_timer_mtimer.c b/lib/utils/timer/fdt_timer_mtimer.c index e1fd0519..1f29f3a2 100644 --- a/lib/utils/timer/fdt_timer_mtimer.c +++ b/lib/utils/timer/fdt_timer_mtimer.c @@ -39,6 +39,7 @@ static int timer_mtimer_cold_init(const void *fdt, int nodeoff, struct aclint_mtimer_data *mt; const struct timer_mtimer_quirks *quirks = match->data; bool is_clint = quirks && quirks->is_clint; + bool is_ref = false; mtn = sbi_zalloc(sizeof(*mtn)); if (!mtn) @@ -110,13 +111,16 @@ static int timer_mtimer_cold_init(const void *fdt, int nodeoff, } /* - * Select first MTIMER device with no associated HARTs as our - * reference MTIMER device. This is only a temporary strategy - * of selecting reference MTIMER device. In future, we might - * define an optional DT property or some other mechanism to - * help us select the reference MTIMER device. + * If we have a DT property to indicate which MTIMER is the reference, + * select the first MTIMER device that has it. Otherwise, select the + * first MTIMER device with no associated HARTs as our reference. */ - if (!mt->hart_count && !mt_reference) { + if (fdt_getprop(fdt, nodeoff, "riscv,reference-mtimer", NULL)) + is_ref = true; + else if (!mt->hart_count) + is_ref = true; + + if (is_ref && !mt_reference) { mt_reference = mt; /* * Set reference for already propbed MTIMER devices |