On ARM, it is necessary to use the _relaxed versions of read[bl] and
write[bl] to ensure we do the correct endianness conversion when running in
big endian.
Keep using avr32 __raw version on avr32 to avoid breakage.
Signed-off-by: Alexandre Belloni <[email protected]>
---
This patch applies after [PATCH v4 0/5] tty/serial: at91: add support to FIFOs
http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/353704.html
drivers/tty/serial/atmel_serial.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index e91b3b2f0590..451acf054281 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -194,6 +194,7 @@ to_atmel_uart_port(struct uart_port *uart)
return container_of(uart, struct atmel_uart_port, uart);
}
+#ifdef CONFIG_AVR32
static inline u32 atmel_uart_readl(struct uart_port *port, u32 reg)
{
return __raw_readl(port->membase + reg);
@@ -213,6 +214,27 @@ static inline void atmel_uart_writeb(struct uart_port *port, u32 reg, u8 value)
{
__raw_writeb(value, port->membase + reg);
}
+#else
+static inline u32 atmel_uart_readl(struct uart_port *port, u32 reg)
+{
+ return readl_relaxed(port->membase + reg);
+}
+
+static inline void atmel_uart_writel(struct uart_port *port, u32 reg, u32 value)
+{
+ writel_relaxed(value, port->membase + reg);
+}
+
+static inline u8 atmel_uart_readb(struct uart_port *port, u32 reg)
+{
+ return readb_relaxed(port->membase + reg);
+}
+
+static inline void atmel_uart_writeb(struct uart_port *port, u32 reg, u8 value)
+{
+ writeb_relaxed(value, port->membase + reg);
+}
+#endif
#ifdef CONFIG_SERIAL_ATMEL_PDC
static bool atmel_use_pdc_rx(struct uart_port *port)
--
2.1.4
Hi Alexandre,
On 07/20/2015 09:56 AM, Alexandre Belloni wrote:
> On ARM, it is necessary to use the _relaxed versions of read[bl] and
> write[bl] to ensure we do the correct endianness conversion when running in
> big endian.
> Keep using avr32 __raw version on avr32 to avoid breakage.
>
> Signed-off-by: Alexandre Belloni <[email protected]>
> ---
>
> This patch applies after [PATCH v4 0/5] tty/serial: at91: add support to FIFOs
> http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/353704.html
>
> drivers/tty/serial/atmel_serial.c | 22 ++++++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index e91b3b2f0590..451acf054281 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -194,6 +194,7 @@ to_atmel_uart_port(struct uart_port *uart)
> return container_of(uart, struct atmel_uart_port, uart);
> }
>
> +#ifdef CONFIG_AVR32
The whole point of i/o accessors is to encapsulate arch-specific
differences, so one of these arches isn't doing it right, or the wrong
i/o accessors are being used.
In any event, serial drivers can't start taking on per-arch conditional
compilation.
Regards,
Peter Hurley
PS - The $subject doesn't really match the patch; this is basically adding
big-endian support on little-endian arches.
> static inline u32 atmel_uart_readl(struct uart_port *port, u32 reg)
> {
> return __raw_readl(port->membase + reg);
> @@ -213,6 +214,27 @@ static inline void atmel_uart_writeb(struct uart_port *port, u32 reg, u8 value)
> {
> __raw_writeb(value, port->membase + reg);
> }
> +#else
> +static inline u32 atmel_uart_readl(struct uart_port *port, u32 reg)
> +{
> + return readl_relaxed(port->membase + reg);
> +}
> +
> +static inline void atmel_uart_writel(struct uart_port *port, u32 reg, u32 value)
> +{
> + writel_relaxed(value, port->membase + reg);
> +}
> +
> +static inline u8 atmel_uart_readb(struct uart_port *port, u32 reg)
> +{
> + return readb_relaxed(port->membase + reg);
> +}
> +
> +static inline void atmel_uart_writeb(struct uart_port *port, u32 reg, u8 value)
> +{
> + writeb_relaxed(value, port->membase + reg);
> +}
> +#endif
>
> #ifdef CONFIG_SERIAL_ATMEL_PDC
> static bool atmel_use_pdc_rx(struct uart_port *port)
>
Hi,
(adding Hans in Cc)
On 20/07/2015 at 15:05:39 -0400, Peter Hurley wrote :
> Hi Alexandre,
>
> On 07/20/2015 09:56 AM, Alexandre Belloni wrote:
> > On ARM, it is necessary to use the _relaxed versions of read[bl] and
> > write[bl] to ensure we do the correct endianness conversion when running in
> > big endian.
> > Keep using avr32 __raw version on avr32 to avoid breakage.
> >
> > Signed-off-by: Alexandre Belloni <[email protected]>
> > ---
> >
> > This patch applies after [PATCH v4 0/5] tty/serial: at91: add support to FIFOs
> > http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/353704.html
> >
> > drivers/tty/serial/atmel_serial.c | 22 ++++++++++++++++++++++
> > 1 file changed, 22 insertions(+)
> >
> > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> > index e91b3b2f0590..451acf054281 100644
> > --- a/drivers/tty/serial/atmel_serial.c
> > +++ b/drivers/tty/serial/atmel_serial.c
> > @@ -194,6 +194,7 @@ to_atmel_uart_port(struct uart_port *uart)
> > return container_of(uart, struct atmel_uart_port, uart);
> > }
> >
> > +#ifdef CONFIG_AVR32
>
> The whole point of i/o accessors is to encapsulate arch-specific
> differences, so one of these arches isn't doing it right, or the wrong
> i/o accessors are being used.
>
I'm not an avr32 specialist but I think __raw accessors are doing big
endian accesses but _relaxed accessors are doing litlle endian accesses.
Maybe Hans can clarify what's needed here.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com