diff mbox series

[v3,2/2] riscv: Add support to determine no. of L2 cache way enabled

Message ID 1578897500-23897-3-git-send-email-yash.shah@sifive.com (mailing list archive)
State New, archived
Headers show
Series cacheinfo support to read no. of L2 cache ways enabled | expand

Commit Message

Yash Shah Jan. 13, 2020, 6:38 a.m. UTC
In order to determine the number of L2 cache ways enabled at runtime,
implement a private attribute ("number_of_ways_enabled"). Reading this
attribute returns the number of enabled L2 cache ways at runtime.

Using riscv_set_cacheinfo_ops() hook a custom function, that returns
this private attribute, to the generic ops structure which is used by
cache_get_priv_group() in cacheinfo framework.

Signed-off-by: Yash Shah <yash.shah@sifive.com>
---
 drivers/soc/sifive/sifive_l2_cache.c | 38 ++++++++++++++++++++++++++++++++++++
 include/soc/sifive/sifive_l2_cache.h |  2 ++
 2 files changed, 40 insertions(+)

Comments

Anup Patel Jan. 14, 2020, 5 a.m. UTC | #1
On Mon, Jan 13, 2020 at 12:09 PM Yash Shah <yash.shah@sifive.com> wrote:
>
> In order to determine the number of L2 cache ways enabled at runtime,
> implement a private attribute ("number_of_ways_enabled"). Reading this
> attribute returns the number of enabled L2 cache ways at runtime.
>
> Using riscv_set_cacheinfo_ops() hook a custom function, that returns
> this private attribute, to the generic ops structure which is used by
> cache_get_priv_group() in cacheinfo framework.
>
> Signed-off-by: Yash Shah <yash.shah@sifive.com>
> ---
>  drivers/soc/sifive/sifive_l2_cache.c | 38 ++++++++++++++++++++++++++++++++++++
>  include/soc/sifive/sifive_l2_cache.h |  2 ++
>  2 files changed, 40 insertions(+)
>
> diff --git a/drivers/soc/sifive/sifive_l2_cache.c b/drivers/soc/sifive/sifive_l2_cache.c
> index a506939..8741885 100644
> --- a/drivers/soc/sifive/sifive_l2_cache.c
> +++ b/drivers/soc/sifive/sifive_l2_cache.c
> @@ -9,6 +9,8 @@
>  #include <linux/interrupt.h>
>  #include <linux/of_irq.h>
>  #include <linux/of_address.h>
> +#include <linux/device.h>
> +#include <asm/cacheinfo.h>
>  #include <soc/sifive/sifive_l2_cache.h>
>
>  #define SIFIVE_L2_DIRECCFIX_LOW 0x100
> @@ -31,6 +33,7 @@
>
>  static void __iomem *l2_base;
>  static int g_irq[SIFIVE_L2_MAX_ECCINTR];
> +static struct riscv_cacheinfo_ops l2_cache_ops;
>
>  enum {
>         DIR_CORR = 0,
> @@ -107,6 +110,38 @@ int unregister_sifive_l2_error_notifier(struct notifier_block *nb)
>  }
>  EXPORT_SYMBOL_GPL(unregister_sifive_l2_error_notifier);
>
> +int sifive_l2_largest_wayenabled(void)
> +{
> +       return readl(l2_base + SIFIVE_L2_WAYENABLE);
> +}

The sifine_l2_largest_wayenabled() is not called from anywhere else
so make it static and rename it to l2_largest_wayenabled().

> +
> +static ssize_t number_of_ways_enabled_show(struct device *dev,
> +                                          struct device_attribute *attr,
> +                                          char *buf)
> +{
> +       return sprintf(buf, "%u\n", sifive_l2_largest_wayenabled());
> +}
> +
> +static DEVICE_ATTR_RO(number_of_ways_enabled);
> +
> +static struct attribute *priv_attrs[] = {
> +       &dev_attr_number_of_ways_enabled.attr,
> +       NULL,
> +};
> +
> +static const struct attribute_group priv_attr_group = {
> +       .attrs = priv_attrs,
> +};
> +
> +const struct attribute_group *l2_get_priv_group(struct cacheinfo *this_leaf)
> +{
> +       /* We want to use private group for L2 cache only */
> +       if (this_leaf->level == 2)
> +               return &priv_attr_group;
> +       else
> +               return NULL;
> +}
> +
>  static irqreturn_t l2_int_handler(int irq, void *device)
>  {
>         unsigned int add_h, add_l;
> @@ -170,6 +205,9 @@ static int __init sifive_l2_init(void)
>
>         l2_config_read();
>
> +       l2_cache_ops.get_priv_group = l2_get_priv_group;
> +       riscv_set_cacheinfo_ops(&l2_cache_ops);
> +
>  #ifdef CONFIG_DEBUG_FS
>         setup_sifive_debug();
>  #endif
> diff --git a/include/soc/sifive/sifive_l2_cache.h b/include/soc/sifive/sifive_l2_cache.h
> index 92ade10..55feff5 100644
> --- a/include/soc/sifive/sifive_l2_cache.h
> +++ b/include/soc/sifive/sifive_l2_cache.h
> @@ -10,6 +10,8 @@
>  extern int register_sifive_l2_error_notifier(struct notifier_block *nb);
>  extern int unregister_sifive_l2_error_notifier(struct notifier_block *nb);
>
> +int sifive_l2_largest_wayenabled(void);
> +

You can drop the sifive_l2_largest_wayenabled() declaration from here.

>  #define SIFIVE_L2_ERR_TYPE_CE 0
>  #define SIFIVE_L2_ERR_TYPE_UE 1
>
> --
> 2.7.4
>

Apart from above it looks good.

Reviewed-by: Anup Patel <anup@brainfault.org>

Regards,
Anup
Yash Shah Jan. 14, 2020, 7 a.m. UTC | #2
> -----Original Message-----
> From: Anup Patel <anup@brainfault.org>
> Sent: 14 January 2020 10:30
> To: Yash Shah <yash.shah@sifive.com>
> Cc: Paul Walmsley ( Sifive) <paul.walmsley@sifive.com>; Palmer Dabbelt
> <palmer@dabbelt.com>; Albert Ou <aou@eecs.berkeley.edu>; Allison
> Randal <allison@lohutok.net>; Alexios Zavras <alexios.zavras@intel.com>;
> Greg Kroah-Hartman <gregkh@linuxfoundation.org>; Thomas Gleixner
> <tglx@linutronix.de>; bp@suse.de; linux-riscv <linux-
> riscv@lists.infradead.org>; linux-kernel@vger.kernel.org List <linux-
> kernel@vger.kernel.org>; Sachin Ghadi <sachin.ghadi@sifive.com>
> Subject: Re: [PATCH v3 2/2] riscv: Add support to determine no. of L2 cache
> way enabled
> 
> On Mon, Jan 13, 2020 at 12:09 PM Yash Shah <yash.shah@sifive.com> wrote:
> >
> > In order to determine the number of L2 cache ways enabled at runtime,
> > implement a private attribute ("number_of_ways_enabled"). Reading this
> > attribute returns the number of enabled L2 cache ways at runtime.
> >
> > Using riscv_set_cacheinfo_ops() hook a custom function, that returns
> > this private attribute, to the generic ops structure which is used by
> > cache_get_priv_group() in cacheinfo framework.
> >
> > Signed-off-by: Yash Shah <yash.shah@sifive.com>
> > ---
> >  drivers/soc/sifive/sifive_l2_cache.c | 38
> > ++++++++++++++++++++++++++++++++++++
> >  include/soc/sifive/sifive_l2_cache.h |  2 ++
> >  2 files changed, 40 insertions(+)
> >
> > diff --git a/drivers/soc/sifive/sifive_l2_cache.c
> > b/drivers/soc/sifive/sifive_l2_cache.c
> > index a506939..8741885 100644
> > --- a/drivers/soc/sifive/sifive_l2_cache.c
> > +++ b/drivers/soc/sifive/sifive_l2_cache.c
> > @@ -9,6 +9,8 @@
> >  #include <linux/interrupt.h>
> >  #include <linux/of_irq.h>
> >  #include <linux/of_address.h>
> > +#include <linux/device.h>
> > +#include <asm/cacheinfo.h>
> >  #include <soc/sifive/sifive_l2_cache.h>
> >
> >  #define SIFIVE_L2_DIRECCFIX_LOW 0x100 @@ -31,6 +33,7 @@
> >
> >  static void __iomem *l2_base;
> >  static int g_irq[SIFIVE_L2_MAX_ECCINTR];
> > +static struct riscv_cacheinfo_ops l2_cache_ops;
> >
> >  enum {
> >         DIR_CORR = 0,
> > @@ -107,6 +110,38 @@ int unregister_sifive_l2_error_notifier(struct
> > notifier_block *nb)  }
> > EXPORT_SYMBOL_GPL(unregister_sifive_l2_error_notifier);
> >
> > +int sifive_l2_largest_wayenabled(void)
> > +{
> > +       return readl(l2_base + SIFIVE_L2_WAYENABLE); }
> 
> The sifine_l2_largest_wayenabled() is not called from anywhere else so
> make it static and rename it to l2_largest_wayenabled().

Sure will do that in v4

> 
> > +
> > +static ssize_t number_of_ways_enabled_show(struct device *dev,
> > +                                          struct device_attribute *attr,
> > +                                          char *buf) {
> > +       return sprintf(buf, "%u\n", sifive_l2_largest_wayenabled()); }
> > +
> > +static DEVICE_ATTR_RO(number_of_ways_enabled);
> > +
> > +static struct attribute *priv_attrs[] = {
> > +       &dev_attr_number_of_ways_enabled.attr,
> > +       NULL,
> > +};
> > +
> > +static const struct attribute_group priv_attr_group = {
> > +       .attrs = priv_attrs,
> > +};
> > +
> > +const struct attribute_group *l2_get_priv_group(struct cacheinfo
> > +*this_leaf) {
> > +       /* We want to use private group for L2 cache only */
> > +       if (this_leaf->level == 2)
> > +               return &priv_attr_group;
> > +       else
> > +               return NULL;
> > +}
> > +
> >  static irqreturn_t l2_int_handler(int irq, void *device)  {
> >         unsigned int add_h, add_l;
> > @@ -170,6 +205,9 @@ static int __init sifive_l2_init(void)
> >
> >         l2_config_read();
> >
> > +       l2_cache_ops.get_priv_group = l2_get_priv_group;
> > +       riscv_set_cacheinfo_ops(&l2_cache_ops);
> > +
> >  #ifdef CONFIG_DEBUG_FS
> >         setup_sifive_debug();
> >  #endif
> > diff --git a/include/soc/sifive/sifive_l2_cache.h
> > b/include/soc/sifive/sifive_l2_cache.h
> > index 92ade10..55feff5 100644
> > --- a/include/soc/sifive/sifive_l2_cache.h
> > +++ b/include/soc/sifive/sifive_l2_cache.h
> > @@ -10,6 +10,8 @@
> >  extern int register_sifive_l2_error_notifier(struct notifier_block
> > *nb);  extern int unregister_sifive_l2_error_notifier(struct
> > notifier_block *nb);
> >
> > +int sifive_l2_largest_wayenabled(void);
> > +
> 
> You can drop the sifive_l2_largest_wayenabled() declaration from here.
> 
> >  #define SIFIVE_L2_ERR_TYPE_CE 0
> >  #define SIFIVE_L2_ERR_TYPE_UE 1
> >
> > --
> > 2.7.4
> >
> 
> Apart from above it looks good.
> 
> Reviewed-by: Anup Patel <anup@brainfault.org>

Thanks.

- Yash

> 
> Regards,
> Anup
diff mbox series

Patch

diff --git a/drivers/soc/sifive/sifive_l2_cache.c b/drivers/soc/sifive/sifive_l2_cache.c
index a506939..8741885 100644
--- a/drivers/soc/sifive/sifive_l2_cache.c
+++ b/drivers/soc/sifive/sifive_l2_cache.c
@@ -9,6 +9,8 @@ 
 #include <linux/interrupt.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
+#include <linux/device.h>
+#include <asm/cacheinfo.h>
 #include <soc/sifive/sifive_l2_cache.h>
 
 #define SIFIVE_L2_DIRECCFIX_LOW 0x100
@@ -31,6 +33,7 @@ 
 
 static void __iomem *l2_base;
 static int g_irq[SIFIVE_L2_MAX_ECCINTR];
+static struct riscv_cacheinfo_ops l2_cache_ops;
 
 enum {
 	DIR_CORR = 0,
@@ -107,6 +110,38 @@  int unregister_sifive_l2_error_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(unregister_sifive_l2_error_notifier);
 
+int sifive_l2_largest_wayenabled(void)
+{
+	return readl(l2_base + SIFIVE_L2_WAYENABLE);
+}
+
+static ssize_t number_of_ways_enabled_show(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	return sprintf(buf, "%u\n", sifive_l2_largest_wayenabled());
+}
+
+static DEVICE_ATTR_RO(number_of_ways_enabled);
+
+static struct attribute *priv_attrs[] = {
+	&dev_attr_number_of_ways_enabled.attr,
+	NULL,
+};
+
+static const struct attribute_group priv_attr_group = {
+	.attrs = priv_attrs,
+};
+
+const struct attribute_group *l2_get_priv_group(struct cacheinfo *this_leaf)
+{
+	/* We want to use private group for L2 cache only */
+	if (this_leaf->level == 2)
+		return &priv_attr_group;
+	else
+		return NULL;
+}
+
 static irqreturn_t l2_int_handler(int irq, void *device)
 {
 	unsigned int add_h, add_l;
@@ -170,6 +205,9 @@  static int __init sifive_l2_init(void)
 
 	l2_config_read();
 
+	l2_cache_ops.get_priv_group = l2_get_priv_group;
+	riscv_set_cacheinfo_ops(&l2_cache_ops);
+
 #ifdef CONFIG_DEBUG_FS
 	setup_sifive_debug();
 #endif
diff --git a/include/soc/sifive/sifive_l2_cache.h b/include/soc/sifive/sifive_l2_cache.h
index 92ade10..55feff5 100644
--- a/include/soc/sifive/sifive_l2_cache.h
+++ b/include/soc/sifive/sifive_l2_cache.h
@@ -10,6 +10,8 @@ 
 extern int register_sifive_l2_error_notifier(struct notifier_block *nb);
 extern int unregister_sifive_l2_error_notifier(struct notifier_block *nb);
 
+int sifive_l2_largest_wayenabled(void);
+
 #define SIFIVE_L2_ERR_TYPE_CE 0
 #define SIFIVE_L2_ERR_TYPE_UE 1