From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chen-Yu Tsai Subject: Re: [PATCH 2/3] dmaengine: sun6i: Add support for Allwinner A23 (sun8i) variant Date: Tue, 16 Sep 2014 22:13:27 +0800 Message-ID: References: <1410616381-30226-1-git-send-email-wens@csie.org> <1410616381-30226-3-git-send-email-wens@csie.org> <20140916103540.GF9948@lukather> Reply-To: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org In-Reply-To: <20140916103540.GF9948@lukather> List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Maxime Ripard Cc: Vinod Koul , Dan Williams , Grant Likely , Rob Herring , linux-arm-kernel , linux-sunxi , dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree List-Id: devicetree@vger.kernel.org On Tue, Sep 16, 2014 at 6:35 PM, Maxime Ripard wrote: > On Sat, Sep 13, 2014 at 09:53:00PM +0800, Chen-Yu Tsai wrote: >> The A23 SoC has the same dma engine as the A31 (sun6i), with a >> reduced amount of endpoints and physical channels. Add the proper >> config data and compatible string to support it. >> >> A slight difference in sun8i is an undocumented register needs >> to be toggled for dma to function. >> >> Signed-off-by: Chen-Yu Tsai >> --- >> Documentation/devicetree/bindings/dma/sun6i-dma.txt | 2 +- >> drivers/dma/Kconfig | 4 ++-- >> drivers/dma/sun6i-dma.c | 20 ++++++++++++++++++++ >> 3 files changed, 23 insertions(+), 3 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/dma/sun6i-dma.txt b/Documentation/devicetree/bindings/dma/sun6i-dma.txt >> index 3e145c1..9cdcba24d 100644 >> --- a/Documentation/devicetree/bindings/dma/sun6i-dma.txt >> +++ b/Documentation/devicetree/bindings/dma/sun6i-dma.txt >> @@ -4,7 +4,7 @@ This driver follows the generic DMA bindings defined in dma.txt. >> >> Required properties: >> >> -- compatible: Must be "allwinner,sun6i-a31-dma" >> +- compatible: Must be "allwinner,sun6i-a31-dma" or "allwinner,sun8i-a23-dma" >> - reg: Should contain the registers base address and length >> - interrupts: Should contain a reference to the interrupt used by this device >> - clocks: Should contain a reference to the parent AHB clock >> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig >> index 9b1ea0e..5361aa7 100644 >> --- a/drivers/dma/Kconfig >> +++ b/drivers/dma/Kconfig >> @@ -395,12 +395,12 @@ config XILINX_VDMA >> >> config DMA_SUN6I >> tristate "Allwinner A31 SoCs DMA support" >> - depends on MACH_SUN6I || COMPILE_TEST >> + depends on MACH_SUN6I || MACH_SUN8I || COMPILE_TEST >> depends on RESET_CONTROLLER >> select DMA_ENGINE >> select DMA_VIRTUAL_CHANNELS >> help >> - Support for the DMA engine for Allwinner A31 SoCs. >> + Support for the DMA engine first found in Allwinner A31 SoCs. >> >> config NBPFAXI_DMA >> tristate "Renesas Type-AXI NBPF DMA support" >> diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c >> index 89ca0c4..29667dd 100644 >> --- a/drivers/dma/sun6i-dma.c >> +++ b/drivers/dma/sun6i-dma.c >> @@ -878,8 +878,20 @@ static struct sun6i_dma_config sun6i_a31_dma_cfg = { >> .nr_max_vchans = 53, >> }; >> >> +/* >> + * The A23 only has 8 physical channels, a maximum DRQ port id of 24, >> + * and a total of 37 usable source and destination endpoints. >> + */ >> + >> +static struct sun6i_dma_config sun8i_a23_dma_cfg = { >> + .nr_max_channels = 8, >> + .nr_max_requests = 24, >> + .nr_max_vchans = 37, >> +}; >> + >> static struct of_device_id sun6i_dma_match[] = { >> { .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg }, >> + { .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg }, >> { /* sentinel */ } >> }; >> >> @@ -1008,6 +1020,14 @@ static int sun6i_dma_probe(struct platform_device *pdev) >> goto err_dma_unregister; >> } >> >> + /* >> + * sun8i variant requires us to toggle an undocumented register, >> + * as seen in Allwinner's SDK. > > The BSP I have has this: > > static void sunxi_dma_hw_init(struct sunxi_dmadev *dev) > { > struct sunxi_dmadev *sunxi_dev = dev; > > clk_prepare_enable(sunxi_dev->ahb_clk); > #ifdef CONFIG_ARCH_SUN8IW3 > writel(0x04, sunxi_dev->base + DMA_GATE); > #endif > } > > /* All is ok, and open the clock */ > sunxi_dma_hw_init(sunxi_dev); > > So I guess we can say that it's not that undocumented :) That's right. I meant undocumented in the user manual. I did reference the SDK in the comment, didn't I? :) ChenYu From mboxrd@z Thu Jan 1 00:00:00 1970 From: wens@csie.org (Chen-Yu Tsai) Date: Tue, 16 Sep 2014 22:13:27 +0800 Subject: [PATCH 2/3] dmaengine: sun6i: Add support for Allwinner A23 (sun8i) variant In-Reply-To: <20140916103540.GF9948@lukather> References: <1410616381-30226-1-git-send-email-wens@csie.org> <1410616381-30226-3-git-send-email-wens@csie.org> <20140916103540.GF9948@lukather> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Sep 16, 2014 at 6:35 PM, Maxime Ripard wrote: > On Sat, Sep 13, 2014 at 09:53:00PM +0800, Chen-Yu Tsai wrote: >> The A23 SoC has the same dma engine as the A31 (sun6i), with a >> reduced amount of endpoints and physical channels. Add the proper >> config data and compatible string to support it. >> >> A slight difference in sun8i is an undocumented register needs >> to be toggled for dma to function. >> >> Signed-off-by: Chen-Yu Tsai >> --- >> Documentation/devicetree/bindings/dma/sun6i-dma.txt | 2 +- >> drivers/dma/Kconfig | 4 ++-- >> drivers/dma/sun6i-dma.c | 20 ++++++++++++++++++++ >> 3 files changed, 23 insertions(+), 3 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/dma/sun6i-dma.txt b/Documentation/devicetree/bindings/dma/sun6i-dma.txt >> index 3e145c1..9cdcba24d 100644 >> --- a/Documentation/devicetree/bindings/dma/sun6i-dma.txt >> +++ b/Documentation/devicetree/bindings/dma/sun6i-dma.txt >> @@ -4,7 +4,7 @@ This driver follows the generic DMA bindings defined in dma.txt. >> >> Required properties: >> >> -- compatible: Must be "allwinner,sun6i-a31-dma" >> +- compatible: Must be "allwinner,sun6i-a31-dma" or "allwinner,sun8i-a23-dma" >> - reg: Should contain the registers base address and length >> - interrupts: Should contain a reference to the interrupt used by this device >> - clocks: Should contain a reference to the parent AHB clock >> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig >> index 9b1ea0e..5361aa7 100644 >> --- a/drivers/dma/Kconfig >> +++ b/drivers/dma/Kconfig >> @@ -395,12 +395,12 @@ config XILINX_VDMA >> >> config DMA_SUN6I >> tristate "Allwinner A31 SoCs DMA support" >> - depends on MACH_SUN6I || COMPILE_TEST >> + depends on MACH_SUN6I || MACH_SUN8I || COMPILE_TEST >> depends on RESET_CONTROLLER >> select DMA_ENGINE >> select DMA_VIRTUAL_CHANNELS >> help >> - Support for the DMA engine for Allwinner A31 SoCs. >> + Support for the DMA engine first found in Allwinner A31 SoCs. >> >> config NBPFAXI_DMA >> tristate "Renesas Type-AXI NBPF DMA support" >> diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c >> index 89ca0c4..29667dd 100644 >> --- a/drivers/dma/sun6i-dma.c >> +++ b/drivers/dma/sun6i-dma.c >> @@ -878,8 +878,20 @@ static struct sun6i_dma_config sun6i_a31_dma_cfg = { >> .nr_max_vchans = 53, >> }; >> >> +/* >> + * The A23 only has 8 physical channels, a maximum DRQ port id of 24, >> + * and a total of 37 usable source and destination endpoints. >> + */ >> + >> +static struct sun6i_dma_config sun8i_a23_dma_cfg = { >> + .nr_max_channels = 8, >> + .nr_max_requests = 24, >> + .nr_max_vchans = 37, >> +}; >> + >> static struct of_device_id sun6i_dma_match[] = { >> { .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg }, >> + { .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg }, >> { /* sentinel */ } >> }; >> >> @@ -1008,6 +1020,14 @@ static int sun6i_dma_probe(struct platform_device *pdev) >> goto err_dma_unregister; >> } >> >> + /* >> + * sun8i variant requires us to toggle an undocumented register, >> + * as seen in Allwinner's SDK. > > The BSP I have has this: > > static void sunxi_dma_hw_init(struct sunxi_dmadev *dev) > { > struct sunxi_dmadev *sunxi_dev = dev; > > clk_prepare_enable(sunxi_dev->ahb_clk); > #ifdef CONFIG_ARCH_SUN8IW3 > writel(0x04, sunxi_dev->base + DMA_GATE); > #endif > } > > /* All is ok, and open the clock */ > sunxi_dma_hw_init(sunxi_dev); > > So I guess we can say that it's not that undocumented :) That's right. I meant undocumented in the user manual. I did reference the SDK in the comment, didn't I? :) ChenYu