Re: [PATCH v2 3/6] soc: sifive: ccache: determine the cache level from dts

From: Zong Li
Date: Mon Sep 05 2022 - 21:58:00 EST


<Conor.Dooley@xxxxxxxxxxxxx> 於 2022年9月6日 週二 凌晨2:56寫道:
>
> On 05/09/2022 09:31, Zong Li wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> >
> > Composable cache could be L2 or L3 cache, use 'cache-level' property of
> > device node to determine the level.
> >
> > Signed-off-by: Zong Li <zong.li@xxxxxxxxxx>
> > Signed-off-by: Greentime Hu <greentime.hu@xxxxxxxxxx>
> > ---
> > drivers/soc/sifive/sifive_ccache.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/soc/sifive/sifive_ccache.c b/drivers/soc/sifive/sifive_ccache.c
> > index 1b16a196547f..0e0eb85c94d8 100644
> > --- a/drivers/soc/sifive/sifive_ccache.c
> > +++ b/drivers/soc/sifive/sifive_ccache.c
> > @@ -38,6 +38,7 @@
> > static void __iomem *ccache_base;
> > static int g_irq[SIFIVE_CCACHE_MAX_ECCINTR];
> > static struct riscv_cacheinfo_ops ccache_cache_ops;
> > +static int level;
>
> Can you have a system with a composable l2 & l3 cache?

We don't have a system with composable L2 and L3 cache at same time.
But as I mentioned in the thread of second patch, we use another cache
as L2 when the composable cache used for L3.

>
> >
> > enum {
> > DIR_CORR = 0,
> > @@ -143,7 +144,7 @@ static const struct attribute_group priv_attr_group = {
> > static const struct attribute_group *ccache_get_priv_group(struct cacheinfo *this_leaf)
> > {
> > /* We want to use private group for composable cache only */
> > - if (this_leaf->level == 2)
> > + if (this_leaf->level == level)
> > return &priv_attr_group;
> > else
> > return NULL;
> > @@ -210,6 +211,9 @@ static int __init sifive_ccache_init(void)
> > if (!ccache_base)
> > return -ENOMEM;
> >
> > + if (of_property_read_u32(np, "cache-level", &level))
> > + return -ENODEV;
> > +
> > intr_num = of_property_count_u32_elems(np, "interrupts");
> > if (!intr_num) {
> > pr_err("CCACHE: no interrupts property\n");
> > --
> > 2.17.1
> >
>