New helper to print named bits of some value (think flags fields).
Signed-off-by: Gerd Hoffmann <[email protected]>
---
include/drm/drm_print.h | 3 +++
drivers/gpu/drm/drm_print.c | 33 +++++++++++++++++++++++++++++++++
2 files changed, 36 insertions(+)
diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
index 112165d3195d..12d4916254b4 100644
--- a/include/drm/drm_print.h
+++ b/include/drm/drm_print.h
@@ -89,6 +89,9 @@ __printf(2, 3)
void drm_printf(struct drm_printer *p, const char *f, ...);
void drm_puts(struct drm_printer *p, const char *str);
void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset);
+void drm_print_bits(struct drm_printer *p,
+ unsigned long value, const char *bits[],
+ unsigned int from, unsigned int to);
__printf(2, 0)
/**
diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index ad302d71eeee..dfa27367ebb8 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -185,6 +185,39 @@ void drm_printf(struct drm_printer *p, const char *f, ...)
}
EXPORT_SYMBOL(drm_printf);
+/**
+ * drm_print_bits - print bits to a &drm_printer stream
+ *
+ * Print bits (in flag fields for example) in human readable form.
+ * The first name in the @bits array is for the bit indexed by @from.
+ *
+ * @p: the &drm_printer
+ * @value: field value.
+ * @bits: Array with bit names.
+ * @from: start of bit range to print (inclusive).
+ * @to: end of bit range to print (exclusive).
+ */
+void drm_print_bits(struct drm_printer *p,
+ unsigned long value, const char *bits[],
+ unsigned int from, unsigned int to)
+{
+ bool first = true;
+ unsigned int i;
+
+ for (i = from; i < to; i++) {
+ if (!(value & (1 << i)))
+ continue;
+ if (WARN_ON_ONCE(!bits[i-from]))
+ continue;
+ drm_printf(p, "%s%s", first ? "" : ",",
+ bits[i-from]);
+ first = false;
+ }
+ if (first)
+ drm_printf(p, "(none)");
+}
+EXPORT_SYMBOL(drm_print_bits);
+
void drm_dev_printk(const struct device *dev, const char *level,
const char *format, ...)
{
--
2.18.1
Am 04.09.19 um 07:47 schrieb Gerd Hoffmann:
> New helper to print named bits of some value (think flags fields).
>
> Signed-off-by: Gerd Hoffmann <[email protected]>
> ---
> include/drm/drm_print.h | 3 +++
> drivers/gpu/drm/drm_print.c | 33 +++++++++++++++++++++++++++++++++
> 2 files changed, 36 insertions(+)
>
> diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
> index 112165d3195d..12d4916254b4 100644
> --- a/include/drm/drm_print.h
> +++ b/include/drm/drm_print.h
> @@ -89,6 +89,9 @@ __printf(2, 3)
> void drm_printf(struct drm_printer *p, const char *f, ...);
> void drm_puts(struct drm_printer *p, const char *str);
> void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset);
> +void drm_print_bits(struct drm_printer *p,
> + unsigned long value, const char *bits[],
> + unsigned int from, unsigned int to);
>
> __printf(2, 0)
> /**
> diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
> index ad302d71eeee..dfa27367ebb8 100644
> --- a/drivers/gpu/drm/drm_print.c
> +++ b/drivers/gpu/drm/drm_print.c
> @@ -185,6 +185,39 @@ void drm_printf(struct drm_printer *p, const char *f, ...)
> }
> EXPORT_SYMBOL(drm_printf);
>
> +/**
> + * drm_print_bits - print bits to a &drm_printer stream
> + *
> + * Print bits (in flag fields for example) in human readable form.
> + * The first name in the @bits array is for the bit indexed by @from.
> + *
> + * @p: the &drm_printer
> + * @value: field value.
> + * @bits: Array with bit names.
> + * @from: start of bit range to print (inclusive).
> + * @to: end of bit range to print (exclusive).
> + */
> +void drm_print_bits(struct drm_printer *p,
> + unsigned long value, const char *bits[],
> + unsigned int from, unsigned int to)
> +{
> + bool first = true;
> + unsigned int i;
> +
> + for (i = from; i < to; i++) {
> + if (!(value & (1 << i)))
> + continue;
> + if (WARN_ON_ONCE(!bits[i-from]))
> + continue;
> + drm_printf(p, "%s%s", first ? "" : ",",
> + bits[i-from]);
> + first = false;
> + }
> + if (first)
> + drm_printf(p, "(none)");
> +}
> +EXPORT_SYMBOL(drm_print_bits);
> +
> void drm_dev_printk(const struct device *dev, const char *level,
> const char *format, ...)
> {
>
Acked-by: Thomas Zimmermann <[email protected]>
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Linux GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany
GF: Felix Imendörffer, Mary Higgins, Sri Rasiah
HRB 21284 (AG Nürnberg)
On Mon, Sep 09, 2019 at 02:46:47PM +0200, Thomas Zimmermann wrote:
>
>
> Am 04.09.19 um 07:47 schrieb Gerd Hoffmann:
> > New helper to print named bits of some value (think flags fields).
> >
> > Signed-off-by: Gerd Hoffmann <[email protected]>
> > ---
> > include/drm/drm_print.h | 3 +++
> > drivers/gpu/drm/drm_print.c | 33 +++++++++++++++++++++++++++++++++
> > 2 files changed, 36 insertions(+)
> >
> > diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
> > index 112165d3195d..12d4916254b4 100644
> > --- a/include/drm/drm_print.h
> > +++ b/include/drm/drm_print.h
> > @@ -89,6 +89,9 @@ __printf(2, 3)
> > void drm_printf(struct drm_printer *p, const char *f, ...);
> > void drm_puts(struct drm_printer *p, const char *str);
> > void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset);
> > +void drm_print_bits(struct drm_printer *p,
> > + unsigned long value, const char *bits[],
> > + unsigned int from, unsigned int to);
> >
> > __printf(2, 0)
> > /**
> > diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
> > index ad302d71eeee..dfa27367ebb8 100644
> > --- a/drivers/gpu/drm/drm_print.c
> > +++ b/drivers/gpu/drm/drm_print.c
> > @@ -185,6 +185,39 @@ void drm_printf(struct drm_printer *p, const char *f, ...)
> > }
> > EXPORT_SYMBOL(drm_printf);
> >
> > +/**
> > + * drm_print_bits - print bits to a &drm_printer stream
> > + *
> > + * Print bits (in flag fields for example) in human readable form.
> > + * The first name in the @bits array is for the bit indexed by @from.
> > + *
> > + * @p: the &drm_printer
> > + * @value: field value.
> > + * @bits: Array with bit names.
> > + * @from: start of bit range to print (inclusive).
> > + * @to: end of bit range to print (exclusive).
Just an aside: At least in drm we generally but the parameter docs above
the free-flow text.
-Daniel
> > + */
> > +void drm_print_bits(struct drm_printer *p,
> > + unsigned long value, const char *bits[],
> > + unsigned int from, unsigned int to)
> > +{
> > + bool first = true;
> > + unsigned int i;
> > +
> > + for (i = from; i < to; i++) {
> > + if (!(value & (1 << i)))
> > + continue;
> > + if (WARN_ON_ONCE(!bits[i-from]))
> > + continue;
> > + drm_printf(p, "%s%s", first ? "" : ",",
> > + bits[i-from]);
> > + first = false;
> > + }
> > + if (first)
> > + drm_printf(p, "(none)");
> > +}
> > +EXPORT_SYMBOL(drm_print_bits);
> > +
> > void drm_dev_printk(const struct device *dev, const char *level,
> > const char *format, ...)
> > {
> >
>
> Acked-by: Thomas Zimmermann <[email protected]>
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Linux GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany
> GF: Felix Imend?rffer, Mary Higgins, Sri Rasiah
> HRB 21284 (AG N?rnberg)
>
> _______________________________________________
> dri-devel mailing list
> [email protected]
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
On Wed, 04 Sep 2019, Gerd Hoffmann <[email protected]> wrote:
> New helper to print named bits of some value (think flags fields).
>
> Signed-off-by: Gerd Hoffmann <[email protected]>
> ---
> include/drm/drm_print.h | 3 +++
> drivers/gpu/drm/drm_print.c | 33 +++++++++++++++++++++++++++++++++
> 2 files changed, 36 insertions(+)
>
> diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
> index 112165d3195d..12d4916254b4 100644
> --- a/include/drm/drm_print.h
> +++ b/include/drm/drm_print.h
> @@ -89,6 +89,9 @@ __printf(2, 3)
> void drm_printf(struct drm_printer *p, const char *f, ...);
> void drm_puts(struct drm_printer *p, const char *str);
> void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset);
> +void drm_print_bits(struct drm_printer *p,
> + unsigned long value, const char *bits[],
> + unsigned int from, unsigned int to);
>
> __printf(2, 0)
> /**
> diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
> index ad302d71eeee..dfa27367ebb8 100644
> --- a/drivers/gpu/drm/drm_print.c
> +++ b/drivers/gpu/drm/drm_print.c
> @@ -185,6 +185,39 @@ void drm_printf(struct drm_printer *p, const char *f, ...)
> }
> EXPORT_SYMBOL(drm_printf);
>
> +/**
> + * drm_print_bits - print bits to a &drm_printer stream
> + *
> + * Print bits (in flag fields for example) in human readable form.
> + * The first name in the @bits array is for the bit indexed by @from.
> + *
> + * @p: the &drm_printer
> + * @value: field value.
> + * @bits: Array with bit names.
> + * @from: start of bit range to print (inclusive).
> + * @to: end of bit range to print (exclusive).
> + */
> +void drm_print_bits(struct drm_printer *p,
> + unsigned long value, const char *bits[],
> + unsigned int from, unsigned int to)
> +{
> + bool first = true;
> + unsigned int i;
> +
> + for (i = from; i < to; i++) {
> + if (!(value & (1 << i)))
> + continue;
for_each_set_bit from bitops.h?
> + if (WARN_ON_ONCE(!bits[i-from]))
> + continue;
> + drm_printf(p, "%s%s", first ? "" : ",",
> + bits[i-from]);
I wonder about the usefulness of from and to, as well as indexing
(i-from) for the strings.
To limit the values to be printed in a more general way than range, you
can use:
drm_print_bits(p, value & GENMASK(h, l), bits);
And obviously to adjust the starting position:
drm_print_bits(p, value >> l, bits);
Seems like a simple len parameter to indicate the ARRAY_SIZE() of bits
would be more straighforward to guard against array overflow.
drm_print_bits(p, value, bits, ARRAY_SIZE(bits));
BR,
Jani.
> + first = false;
> + }
> + if (first)
> + drm_printf(p, "(none)");
> +}
> +EXPORT_SYMBOL(drm_print_bits);
> +
> void drm_dev_printk(const struct device *dev, const char *level,
> const char *format, ...)
> {
--
Jani Nikula, Intel Open Source Graphics Center