| Message ID | 1415710432-12167-1-git-send-email-andy.yan@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Andy, This patch adds the reg-io-width binding. Hence the binding patch should come before it. On 11/11/14 12:53, Andy Yan wrote: > On rockchip rk3288, only word(32-bit) accesses are > permitted for hdmi registers. Byte width accesses (writeb, > readb) generate an imprecise external abort. > > Signed-off-by: Andy Yan <andy.yan@rock-chips.com> > > --- > > } > > static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg) > @@ -1499,6 +1527,23 @@ static int dw_hdmi_bind(struct device *dev, struct device *master, void *data) > struct device_node *ddc_node; > struct resource *iores; > int ret, irq; > + u32 val = 1; > + > + of_property_read_u32(np, "reg-io-width", &val); > + > + switch (val) { > + case 4: > + hdmi->write = dw_hdmi_writel; > + hdmi->read = dw_hdmi_readl; > + break; > + case 1: > + hdmi->write = dw_hdmi_writeb; > + hdmi->read = dw_hdmi_readb; > + break; > + default: > + dev_err(dev, "reg-io-width must be 1 or 4\n"); > + return -EINVAL; > + } The binding patch says this is an optional property. But here if undefined it returns -EINVAL. I would keep it optional and default it to byte access. Regards, ZubairLK
Am Dienstag, den 11.11.2014, 14:20 +0000 schrieb Zubair Lutfullah Kakakhel: > Hi Andy, > > This patch adds the reg-io-width binding. > > Hence the binding patch should come before it. > > > On 11/11/14 12:53, Andy Yan wrote: > > On rockchip rk3288, only word(32-bit) accesses are > > permitted for hdmi registers. Byte width accesses (writeb, > > readb) generate an imprecise external abort. > > > > Signed-off-by: Andy Yan <andy.yan@rock-chips.com> > > > > --- > > > > } > > > > static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg) > > @@ -1499,6 +1527,23 @@ static int dw_hdmi_bind(struct device *dev, struct device *master, void *data) > > struct device_node *ddc_node; > > struct resource *iores; > > int ret, irq; > > + u32 val = 1; > > + > > + of_property_read_u32(np, "reg-io-width", &val); > > + > > + switch (val) { > > + case 4: > > + hdmi->write = dw_hdmi_writel; > > + hdmi->read = dw_hdmi_readl; > > + break; > > + case 1: > > + hdmi->write = dw_hdmi_writeb; > > + hdmi->read = dw_hdmi_readb; > > + break; > > + default: > > + dev_err(dev, "reg-io-width must be 1 or 4\n"); > > + return -EINVAL; > > + } > > The binding patch says this is an optional property. > But here if undefined it returns -EINVAL. > > I would keep it optional and default it to byte access. That's exactly what the patch does. val is initialized to 1, which is not changed if the property could not be found in the DT. The default case will only be taken if the property is present in DT but has any other value than 1 or 4, which is an error. Regards, Lucas
On 11/11/14 14:23, Lucas Stach wrote: > Am Dienstag, den 11.11.2014, 14:20 +0000 schrieb Zubair Lutfullah > Kakakhel: >> Hi Andy, >> >> This patch adds the reg-io-width binding. >> >> Hence the binding patch should come before it. >> >> >> On 11/11/14 12:53, Andy Yan wrote: >>> On rockchip rk3288, only word(32-bit) accesses are >>> permitted for hdmi registers. Byte width accesses (writeb, >>> readb) generate an imprecise external abort. >>> >>> Signed-off-by: Andy Yan <andy.yan@rock-chips.com> >>> >>> --- >>> >>> } >>> >>> static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg) >>> @@ -1499,6 +1527,23 @@ static int dw_hdmi_bind(struct device *dev, struct device *master, void *data) >>> struct device_node *ddc_node; >>> struct resource *iores; >>> int ret, irq; >>> + u32 val = 1; >>> + >>> + of_property_read_u32(np, "reg-io-width", &val); >>> + >>> + switch (val) { >>> + case 4: >>> + hdmi->write = dw_hdmi_writel; >>> + hdmi->read = dw_hdmi_readl; >>> + break; >>> + case 1: >>> + hdmi->write = dw_hdmi_writeb; >>> + hdmi->read = dw_hdmi_readb; >>> + break; >>> + default: >>> + dev_err(dev, "reg-io-width must be 1 or 4\n"); >>> + return -EINVAL; >>> + } >> >> The binding patch says this is an optional property. >> But here if undefined it returns -EINVAL. >> >> I would keep it optional and default it to byte access. > > That's exactly what the patch does. val is initialized to 1, which is > not changed if the property could not be found in the DT. The default > case will only be taken if the property is present in DT but has any > other value than 1 or 4, which is an error. > I missed the initialization. My bad. Thanks ZubairLK
On 2014?11?11? 22:20, Zubair Lutfullah Kakakhel wrote: > Hi Andy, > > This patch adds the reg-io-width binding. > > Hence the binding patch should come before it. > do you mean that I should put dts binding patch before this patch? > On 11/11/14 12:53, Andy Yan wrote: >> On rockchip rk3288, only word(32-bit) accesses are >> permitted for hdmi registers. Byte width accesses (writeb, >> readb) generate an imprecise external abort. >> >> Signed-off-by: Andy Yan <andy.yan@rock-chips.com> >> >> --- >> >> } >> >> static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg) >> @@ -1499,6 +1527,23 @@ static int dw_hdmi_bind(struct device *dev, struct device *master, void *data) >> struct device_node *ddc_node; >> struct resource *iores; >> int ret, irq; >> + u32 val = 1; >> + >> + of_property_read_u32(np, "reg-io-width", &val); >> + >> + switch (val) { >> + case 4: >> + hdmi->write = dw_hdmi_writel; >> + hdmi->read = dw_hdmi_readl; >> + break; >> + case 1: >> + hdmi->write = dw_hdmi_writeb; >> + hdmi->read = dw_hdmi_readb; >> + break; >> + default: >> + dev_err(dev, "reg-io-width must be 1 or 4\n"); >> + return -EINVAL; >> + } > The binding patch says this is an optional property. > But here if undefined it returns -EINVAL. > > I would keep it optional and default it to byte access. if the dts undefined it, the val will be 1. if the dts defined other value except 4 and 1, return -EINVAL > > Regards, > ZubairLK > > > _______________________________________________ > Linux-rockchip mailing list > Linux-rockchip@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-rockchip > > >
On 11/11/14 14:46, Andy Yan wrote: > > On 2014?11?11? 22:20, Zubair Lutfullah Kakakhel wrote: >> Hi Andy, >> >> This patch adds the reg-io-width binding. >> >> Hence the binding patch should come before it. >> > do you mean that I should put dts binding patch > before this patch? Yes. The patch adding the binding to the Documentation folder comes before the driver implementing the binding. ZubairLK >> On 11/11/14 12:53, Andy Yan wrote: >>> On rockchip rk3288, only word(32-bit) accesses are >>> permitted for hdmi registers. Byte width accesses (writeb, >>> readb) generate an imprecise external abort.
diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index e9f0dfe..978c709 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -101,6 +101,11 @@ struct hdmi_data_info { struct hdmi_vmode video_mode; }; +union dw_reg_ptr { + u32 __iomem *p32; + u8 __iomem *p8; +}; + struct dw_hdmi { struct drm_connector connector; struct drm_encoder encoder; @@ -121,20 +126,43 @@ struct dw_hdmi { struct regmap *regmap; struct i2c_adapter *ddc; - void __iomem *regs; + union dw_reg_ptr regs; unsigned int sample_rate; int ratio; + + void (*write)(struct dw_hdmi *hdmi, u8 val, int offset); + u8 (*read)(struct dw_hdmi *hdmi, int offset); }; +static void dw_hdmi_writel(struct dw_hdmi *hdmi, u8 val, int offset) +{ + writel(val, hdmi->regs.p32 + offset); +} + +static u8 dw_hdmi_readl(struct dw_hdmi *hdmi, int offset) +{ + return readl(hdmi->regs.p32 + offset); +} + +static void dw_hdmi_writeb(struct dw_hdmi *hdmi, u8 val, int offset) +{ + writeb(val, hdmi->regs.p8 + offset); +} + +static u8 dw_hdmi_readb(struct dw_hdmi *hdmi, int offset) +{ + return readb(hdmi->regs.p8 + offset); +} + static inline void hdmi_writeb(struct dw_hdmi *hdmi, u8 val, int offset) { - writeb(val, hdmi->regs + offset); + hdmi->write(hdmi, val, offset); } static inline u8 hdmi_readb(struct dw_hdmi *hdmi, int offset) { - return readb(hdmi->regs + offset); + return hdmi->read(hdmi, offset); } static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg) @@ -1499,6 +1527,23 @@ static int dw_hdmi_bind(struct device *dev, struct device *master, void *data) struct device_node *ddc_node; struct resource *iores; int ret, irq; + u32 val = 1; + + of_property_read_u32(np, "reg-io-width", &val); + + switch (val) { + case 4: + hdmi->write = dw_hdmi_writel; + hdmi->read = dw_hdmi_readl; + break; + case 1: + hdmi->write = dw_hdmi_writeb; + hdmi->read = dw_hdmi_readb; + break; + default: + dev_err(dev, "reg-io-width must be 1 or 4\n"); + return -EINVAL; + } ddc_node = of_parse_phandle(np, "ddc-i2c-bus", 0); if (ddc_node) { @@ -1525,9 +1570,9 @@ static int dw_hdmi_bind(struct device *dev, struct device *master, void *data) return ret; iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); - hdmi->regs = devm_ioremap_resource(dev, iores); - if (IS_ERR(hdmi->regs)) - return PTR_ERR(hdmi->regs); + hdmi->regs.p32 = devm_ioremap_resource(dev, iores); + if (IS_ERR(hdmi->regs.p32)) + return PTR_ERR(hdmi->regs.p32); if (hdmi->plat_data->setup) hdmi->priv = hdmi->plat_data->setup(pdev);
On rockchip rk3288, only word(32-bit) accesses are permitted for hdmi registers. Byte width accesses (writeb, readb) generate an imprecise external abort. Signed-off-by: Andy Yan <andy.yan@rock-chips.com> --- Changes in v7: None Changes in v6: - move some modification to patch#6 - refactor register access without reg_shift Changes in v5: - refactor reg-io-width Changes in v4: None Changes in v3: - split multi register access to one indepent patch Changes in v2: None drivers/gpu/drm/bridge/dw_hdmi.c | 57 +++++++++++++++++++++++++++++++++++----- 1 file changed, 51 insertions(+), 6 deletions(-)