From: Jan Charvat <charvj10@fel.cvut.cz>
Signed-off-by: Jan Charvat <charvj10@fel.cvut.cz>
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
---
include/net/can_emu.h | 4 ++++
net/can/can_core.c | 36 ++++++++++++++++++++++++++++++++++++
2 files changed, 40 insertions(+)
diff --git a/include/net/can_emu.h b/include/net/can_emu.h
index c6164dcfb4..7d395fbb9b 100644
--- a/include/net/can_emu.h
+++ b/include/net/can_emu.h
@@ -127,4 +127,8 @@ int can_bus_client_set_filters(CanBusClientState *,
const struct qemu_can_filter *filters,
size_t filters_cnt);
+uint8_t can_dlc2len(uint8_t can_dlc);
+
+uint8_t can_len2dlc(uint8_t len);
+
#endif
diff --git a/net/can/can_core.c b/net/can/can_core.c
index 90f4d8576a..0115d78794 100644
--- a/net/can/can_core.c
+++ b/net/can/can_core.c
@@ -33,6 +33,42 @@
#include "net/can_emu.h"
#include "qom/object_interfaces.h"
+/* CAN DLC to real data length conversion helpers */
+
+static const uint8_t dlc2len[] = {
+ 0, 1, 2, 3, 4, 5, 6, 7,
+ 8, 12, 16, 20, 24, 32, 48, 64
+};
+
+/* get data length from can_dlc with sanitized can_dlc */
+uint8_t can_dlc2len(uint8_t can_dlc)
+{
+ return dlc2len[can_dlc & 0x0F];
+}
+
+static const uint8_t len2dlc[] = {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */
+ 9, 9, 9, 9, /* 9 - 12 */
+ 10, 10, 10, 10, /* 13 - 16 */
+ 11, 11, 11, 11, /* 17 - 20 */
+ 12, 12, 12, 12, /* 21 - 24 */
+ 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
+ 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
+ 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
+ 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
+ 15, 15, 15, 15, 15, 15, 15, 15 /* 57 - 64 */
+};
+
+/* map the sanitized data length to an appropriate data length code */
+uint8_t can_len2dlc(uint8_t len)
+{
+ if (unlikely(len > 64)) {
+ return 0xF;
+ }
+
+ return len2dlc[len];
+}
+
struct CanBusState {
Object object;
--
2.20.1
On Tue, Jul 14, 2020 at 02:20:16PM +0200, pisa@cmp.felk.cvut.cz wrote:
Hi Pavel,
> From: Jan Charvat <charvj10@fel.cvut.cz>
>
> Signed-off-by: Jan Charvat <charvj10@fel.cvut.cz>
> Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
> ---
> include/net/can_emu.h | 4 ++++
> net/can/can_core.c | 36 ++++++++++++++++++++++++++++++++++++
> 2 files changed, 40 insertions(+)
>
> diff --git a/include/net/can_emu.h b/include/net/can_emu.h
> index c6164dcfb4..7d395fbb9b 100644
> --- a/include/net/can_emu.h
> +++ b/include/net/can_emu.h
> @@ -127,4 +127,8 @@ int can_bus_client_set_filters(CanBusClientState *,
> const struct qemu_can_filter *filters,
> size_t filters_cnt);
>
> +uint8_t can_dlc2len(uint8_t can_dlc);
> +
> +uint8_t can_len2dlc(uint8_t len);
> +
These function are aimed for canfd. Perhaps rename these to canfd_dlc2len and
canfd_len2dlc for better distinction?
Rest of the patch looks good to me.
> #endif
> diff --git a/net/can/can_core.c b/net/can/can_core.c
> index 90f4d8576a..0115d78794 100644
> --- a/net/can/can_core.c
> +++ b/net/can/can_core.c
> @@ -33,6 +33,42 @@
> #include "net/can_emu.h"
> #include "qom/object_interfaces.h"
>
> +/* CAN DLC to real data length conversion helpers */
> +
> +static const uint8_t dlc2len[] = {
> + 0, 1, 2, 3, 4, 5, 6, 7,
> + 8, 12, 16, 20, 24, 32, 48, 64
> +};
> +
> +/* get data length from can_dlc with sanitized can_dlc */
> +uint8_t can_dlc2len(uint8_t can_dlc)
> +{
> + return dlc2len[can_dlc & 0x0F];
> +}
> +
> +static const uint8_t len2dlc[] = {
> + 0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */
> + 9, 9, 9, 9, /* 9 - 12 */
> + 10, 10, 10, 10, /* 13 - 16 */
> + 11, 11, 11, 11, /* 17 - 20 */
> + 12, 12, 12, 12, /* 21 - 24 */
> + 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
> + 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
> + 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
> + 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
> + 15, 15, 15, 15, 15, 15, 15, 15 /* 57 - 64 */
> +};
> +
> +/* map the sanitized data length to an appropriate data length code */
> +uint8_t can_len2dlc(uint8_t len)
> +{
> + if (unlikely(len > 64)) {
> + return 0xF;
> + }
> +
> + return len2dlc[len];
> +}
> +
> struct CanBusState {
> Object object;
>
> --
> 2.20.1
>
>
Hello Vikram, On Thursday 03 of September 2020 07:43:34 Vikram Garhwal wrote: > On Tue, Jul 14, 2020 at 02:20:16PM +0200, pisa@cmp.felk.cvut.cz wrote: > Hi Pavel, > > > From: Jan Charvat <charvj10@fel.cvut.cz> > > > > Signed-off-by: Jan Charvat <charvj10@fel.cvut.cz> > > Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz> > > --- > > include/net/can_emu.h | 4 ++++ > > net/can/can_core.c | 36 ++++++++++++++++++++++++++++++++++++ > > 2 files changed, 40 insertions(+) > > > > diff --git a/include/net/can_emu.h b/include/net/can_emu.h > > index c6164dcfb4..7d395fbb9b 100644 > > --- a/include/net/can_emu.h > > +++ b/include/net/can_emu.h > > @@ -127,4 +127,8 @@ int can_bus_client_set_filters(CanBusClientState *, > > const struct qemu_can_filter *filters, > > size_t filters_cnt); > > > > +uint8_t can_dlc2len(uint8_t can_dlc); > > + > > +uint8_t can_len2dlc(uint8_t len); > > + > > These function are aimed for canfd. Perhaps rename these to canfd_dlc2len > and canfd_len2dlc for better distinction? > Rest of the patch looks good to me. I do not insits on name. But function correspond 1:1 to the Linux kernel ones https://elixir.bootlin.com/linux/latest/source/drivers/net/can/dev.c#L34 These functions/tables are very short, but may it be, we should add comment about their origin. This part of original file is Oliver Hartkopp contribution https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/net/can/dev.c?h=v5.9-rc3&id=1e0625facab2e871472472b7df87d8fbe6caf75a some other helpers are from Wolfgang Grandegger and me. Best wishes, Pavel
On Thu, Sep 03, 2020 at 08:12:42AM +0200, Pavel Pisa wrote: Hey Pavel, Thanks for clarifying this and sharing the relevant links. Regards, Vikram > Hello Vikram, > > On Thursday 03 of September 2020 07:43:34 Vikram Garhwal wrote: > > On Tue, Jul 14, 2020 at 02:20:16PM +0200, pisa@cmp.felk.cvut.cz wrote: > > Hi Pavel, > > > > > From: Jan Charvat <charvj10@fel.cvut.cz> > > > > > > Signed-off-by: Jan Charvat <charvj10@fel.cvut.cz> > > > Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz> Reviewed-by: Vikram Garhwal <fnu.vikram@xilinx.com> > > > --- > > > include/net/can_emu.h | 4 ++++ > > > net/can/can_core.c | 36 ++++++++++++++++++++++++++++++++++++ > > > 2 files changed, 40 insertions(+) > > > > > > diff --git a/include/net/can_emu.h b/include/net/can_emu.h > > > index c6164dcfb4..7d395fbb9b 100644 > > > --- a/include/net/can_emu.h > > > +++ b/include/net/can_emu.h > > > @@ -127,4 +127,8 @@ int can_bus_client_set_filters(CanBusClientState *, > > > const struct qemu_can_filter *filters, > > > size_t filters_cnt); > > > > > > +uint8_t can_dlc2len(uint8_t can_dlc); > > > + > > > +uint8_t can_len2dlc(uint8_t len); > > > + > > > > These function are aimed for canfd. Perhaps rename these to canfd_dlc2len > > and canfd_len2dlc for better distinction? > > Rest of the patch looks good to me. > > I do not insits on name. But function correspond 1:1 to the Linux > kernel ones > > https://elixir.bootlin.com/linux/latest/source/drivers/net/can/dev.c#L34 > > These functions/tables are very short, but may it be, we should add comment > about their origin. This part of original file is Oliver Hartkopp > contribution > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/net/can/dev.c?h=v5.9-rc3&id=1e0625facab2e871472472b7df87d8fbe6caf75a > > some other helpers are from Wolfgang Grandegger and me. > > Best wishes, > > Pavel
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