| Message ID | 20210317222946.118125-3-elder@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | net: ipa: support 32-bit targets | expand |
On 3/17/2021 3:29 PM, Alex Elder wrote: > Create a new helper function to encapsulate extracting the > high-order 32 bits of a DMA address. It returns 0 for builds > in which a DMA address is not 64 bits. > > This avoids doing a 32-position shift on a DMA address if it > happens not to be 64 bits wide. > > Signed-off-by: Alex Elder <elder@linaro.org> > --- > drivers/net/ipa/gsi.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ipa/gsi.c b/drivers/net/ipa/gsi.c > index 2119367b93ea9..53698c64cf882 100644 > --- a/drivers/net/ipa/gsi.c > +++ b/drivers/net/ipa/gsi.c > @@ -688,6 +688,16 @@ static void gsi_evt_ring_doorbell(struct gsi *gsi, u32 evt_ring_id, u32 index) > iowrite32(val, gsi->virt + GSI_EV_CH_E_DOORBELL_0_OFFSET(evt_ring_id)); > } > > +/* Encapsulate extracting high-order 32 bits of DMA address */ > +static u32 dma_addr_high32(dma_addr_t addr) > +{ > +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT > + return (u32)(addr >> 32); You can probably use upper_32bits() here... > +#else /* !CONFIG_ARCH_DMA_ADDR_T_64BIT */ > + return 0; > +#endif /* !CONFIG_ARCH_DMA_ADDR_T_64BIT */ > +} > + > /* Program an event ring for use */ > static void gsi_evt_ring_program(struct gsi *gsi, u32 evt_ring_id) > { > @@ -711,7 +721,7 @@ static void gsi_evt_ring_program(struct gsi *gsi, u32 evt_ring_id) > val = evt_ring->ring.addr & GENMASK(31, 0); ...and you can use lower_32bits() here. > iowrite32(val, gsi->virt + GSI_EV_CH_E_CNTXT_2_OFFSET(evt_ring_id)); > > - val = evt_ring->ring.addr >> 32; > + val = dma_addr_high32(evt_ring->ring.addr); Does the compiler do a good job at eliminating the assignment when CONFIG_ARCH_DMA_ADDR_T_64BIT is not defined? > iowrite32(val, gsi->virt + GSI_EV_CH_E_CNTXT_3_OFFSET(evt_ring_id)); > > /* Enable interrupt moderation by setting the moderation delay */ > @@ -819,7 +829,7 @@ static void gsi_channel_program(struct gsi_channel *channel, bool doorbell) > val = channel->tre_ring.addr & GENMASK(31, 0); > iowrite32(val, gsi->virt + GSI_CH_C_CNTXT_2_OFFSET(channel_id)); > > - val = channel->tre_ring.addr >> 32; > + val = dma_addr_high32(channel->tre_ring.addr); > iowrite32(val, gsi->virt + GSI_CH_C_CNTXT_3_OFFSET(channel_id)); > > /* Command channel gets low weighted round-robin priority */ > -- Florian
On 3/17/21 5:47 PM, Florian Fainelli wrote: >> +/* Encapsulate extracting high-order 32 bits of DMA address */ >> +static u32 dma_addr_high32(dma_addr_t addr) >> +{ >> +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT >> + return (u32)(addr >> 32); > You can probably use upper_32bits() here... Where is that defined? I'd be glad to use it. -Alex
On 3/17/2021 3:49 PM, Alex Elder wrote: > On 3/17/21 5:47 PM, Florian Fainelli wrote: >>> +/* Encapsulate extracting high-order 32 bits of DMA address */ >>> +static u32 dma_addr_high32(dma_addr_t addr) >>> +{ >>> +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT >>> + return (u32)(addr >> 32); >> You can probably use upper_32bits() here... > > Where is that defined? I'd be glad to use it. -Alex include/linux/kernel.h, and it is upper_32_bits() and lower_32_bits() sorry about the missing space. -- Florian
On 3/17/21 6:00 PM, Florian Fainelli wrote: > > > On 3/17/2021 3:49 PM, Alex Elder wrote: >> On 3/17/21 5:47 PM, Florian Fainelli wrote: >>>> +/* Encapsulate extracting high-order 32 bits of DMA address */ >>>> +static u32 dma_addr_high32(dma_addr_t addr) >>>> +{ >>>> +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT >>>> + return (u32)(addr >> 32); >>> You can probably use upper_32bits() here... >> >> Where is that defined? I'd be glad to use it. -Alex > > include/linux/kernel.h, and it is upper_32_bits() and lower_32_bits() > sorry about the missing space. That's nice. I'll still use a separate commit (and will credit you with the suggestion) but it will be much smaller. Thanks. I'll post v2 shortly. -Alex
diff --git a/drivers/net/ipa/gsi.c b/drivers/net/ipa/gsi.c index 2119367b93ea9..53698c64cf882 100644 --- a/drivers/net/ipa/gsi.c +++ b/drivers/net/ipa/gsi.c @@ -688,6 +688,16 @@ static void gsi_evt_ring_doorbell(struct gsi *gsi, u32 evt_ring_id, u32 index) iowrite32(val, gsi->virt + GSI_EV_CH_E_DOORBELL_0_OFFSET(evt_ring_id)); } +/* Encapsulate extracting high-order 32 bits of DMA address */ +static u32 dma_addr_high32(dma_addr_t addr) +{ +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT + return (u32)(addr >> 32); +#else /* !CONFIG_ARCH_DMA_ADDR_T_64BIT */ + return 0; +#endif /* !CONFIG_ARCH_DMA_ADDR_T_64BIT */ +} + /* Program an event ring for use */ static void gsi_evt_ring_program(struct gsi *gsi, u32 evt_ring_id) { @@ -711,7 +721,7 @@ static void gsi_evt_ring_program(struct gsi *gsi, u32 evt_ring_id) val = evt_ring->ring.addr & GENMASK(31, 0); iowrite32(val, gsi->virt + GSI_EV_CH_E_CNTXT_2_OFFSET(evt_ring_id)); - val = evt_ring->ring.addr >> 32; + val = dma_addr_high32(evt_ring->ring.addr); iowrite32(val, gsi->virt + GSI_EV_CH_E_CNTXT_3_OFFSET(evt_ring_id)); /* Enable interrupt moderation by setting the moderation delay */ @@ -819,7 +829,7 @@ static void gsi_channel_program(struct gsi_channel *channel, bool doorbell) val = channel->tre_ring.addr & GENMASK(31, 0); iowrite32(val, gsi->virt + GSI_CH_C_CNTXT_2_OFFSET(channel_id)); - val = channel->tre_ring.addr >> 32; + val = dma_addr_high32(channel->tre_ring.addr); iowrite32(val, gsi->virt + GSI_CH_C_CNTXT_3_OFFSET(channel_id)); /* Command channel gets low weighted round-robin priority */
Create a new helper function to encapsulate extracting the high-order 32 bits of a DMA address. It returns 0 for builds in which a DMA address is not 64 bits. This avoids doing a 32-position shift on a DMA address if it happens not to be 64 bits wide. Signed-off-by: Alex Elder <elder@linaro.org> --- drivers/net/ipa/gsi.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) -- 2.27.0