| Message ID | 1415875965-6905-2-git-send-email-ludovic.desroches@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thursday 13 November 2014 11:52:39 Ludovic Desroches wrote: > _relaxed version of readl and writel are not implemented on all > architecture so COMPILE_TEST has to be removed in order to not cause > some build failures. > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > --- > I've queued up Will Deacon's series to enable the relaxed accessors on all architectures, so the Kconfig change should no longer be required in 3.19. Arnd
On Thu, Nov 13, 2014 at 12:01:49PM +0100, Arnd Bergmann wrote: > On Thursday 13 November 2014 11:52:39 Ludovic Desroches wrote: > > _relaxed version of readl and writel are not implemented on all > > architecture so COMPILE_TEST has to be removed in order to not cause > > some build failures. > > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > --- > > > > I've queued up Will Deacon's series to enable the relaxed accessors > on all architectures, so the Kconfig change should no longer > be required in 3.19. Good news. Vinod, I can send a v2 if you want. Ludovic
On Thu, Nov 13, 2014 at 12:01:49PM +0100, Arnd Bergmann wrote: > On Thursday 13 November 2014 11:52:39 Ludovic Desroches wrote: > > _relaxed version of readl and writel are not implemented on all > > architecture so COMPILE_TEST has to be removed in order to not cause > > some build failures. > > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > --- > > > > I've queued up Will Deacon's series to enable the relaxed accessors > on all architectures, so the Kconfig change should no longer > be required in 3.19. And why is _relaxed() version required for thsi driver. Why cant readl(), writel() with barriers do?
On Thu, Nov 13, 2014 at 09:04:49PM +0530, Vinod Koul wrote: > On Thu, Nov 13, 2014 at 12:01:49PM +0100, Arnd Bergmann wrote: > > On Thursday 13 November 2014 11:52:39 Ludovic Desroches wrote: > > > _relaxed version of readl and writel are not implemented on all > > > architecture so COMPILE_TEST has to be removed in order to not cause > > > some build failures. > > > > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > > --- > > > > > > > I've queued up Will Deacon's series to enable the relaxed accessors > > on all architectures, so the Kconfig change should no longer > > be required in 3.19. > And why is _relaxed() version required for thsi driver. Why cant readl(), > writel() with barriers do? Required not but preferred to my mind. I don't need a barrier for all read and write I am performing. Barriers have been added when needed. When you have fixed my code because of the compilation breakage on other architecture, you only change the read and write macros. Currently, there are some redundancies because of the barriers added in the code. To be honest, I have no idea about the performance impact between the use of read/write and read/write_relaxed. Then two choices: - go back to relaxed version, good new can keep COMPILE_TEST thanks to Will Deacon - remove barrier since they are no more needed if using readl/writel Ludovic > > -- > ~Vinod > > -- > To unsubscribe from this list: send the line "unsubscribe dmaengine" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Nov 13, 2014 at 04:45:51PM +0100, Ludovic Desroches wrote: > On Thu, Nov 13, 2014 at 09:04:49PM +0530, Vinod Koul wrote: > > On Thu, Nov 13, 2014 at 12:01:49PM +0100, Arnd Bergmann wrote: > > > On Thursday 13 November 2014 11:52:39 Ludovic Desroches wrote: > > > > _relaxed version of readl and writel are not implemented on all > > > > architecture so COMPILE_TEST has to be removed in order to not cause > > > > some build failures. > > > > > > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > --- > > > > > > > > > > I've queued up Will Deacon's series to enable the relaxed accessors > > > on all architectures, so the Kconfig change should no longer > > > be required in 3.19. > > And why is _relaxed() version required for thsi driver. Why cant readl(), > > writel() with barriers do? > > Required not but preferred to my mind. I don't need a barrier for all > read and write I am performing. Barriers have been added when needed. > > When you have fixed my code because of the compilation breakage on other > architecture, you only change the read and write macros. Currently, there are > some redundancies because of the barriers added in the code. > > To be honest, I have no idea about the performance impact between the > use of read/write and read/write_relaxed. Then two choices: > - go back to relaxed version, good new can keep COMPILE_TEST thanks to > Will Deacon But that would merged after merge window. This was also reported on next. So lets keep this patch for now and you can enabled COMPILE_TEST after next merge window. > - remove barrier since they are no more needed if using readl/writel I think that should be right fix along with checking performance of driver and optimize/stress it So for now, I am applying this whole series.
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index aef8b9d..f2b2c4e 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -109,7 +109,7 @@ config AT_HDMAC config AT_XDMAC tristate "Atmel XDMA support" - depends on (ARCH_AT91 || COMPILE_TEST) + depends on ARCH_AT91 select DMA_ENGINE help Support the Atmel XDMA controller. diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 89c43be..1f53d92 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -248,12 +248,12 @@ static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, uns return atxdmac->regs + (AT_XDMAC_CHAN_REG_BASE + chan_nb * 0x40); } -#define at_xdmac_read(atxdmac, reg) readl((atxdmac)->regs + (reg)) +#define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg)) #define at_xdmac_write(atxdmac, reg, value) \ - writel((value), (atxdmac)->regs + (reg)) + writel_relaxed((value), (atxdmac)->regs + (reg)) -#define at_xdmac_chan_read(atchan, reg) readl((atchan)->ch_regs + (reg)) -#define at_xdmac_chan_write(atchan, reg, value) writel((value), (atchan)->ch_regs + (reg)) +#define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg)) +#define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg)) static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan) {
_relaxed version of readl and writel are not implemented on all architecture so COMPILE_TEST has to be removed in order to not cause some build failures. Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> --- drivers/dma/Kconfig | 2 +- drivers/dma/at_xdmac.c | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-)