| Message ID | 1382517309-6730-1-git-send-email-peter.chen@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Peter, On Wed, Oct 23, 2013 at 6:35 AM, Peter Chen <peter.chen@freescale.com> wrote: > According to Freescale imx28 Errata, "ENGR119653 USB: ARM to USB > register error issue", All USB register write operations must > use the ARM SWP instruction. So, we implement a special ehci_write > for imx28. > > Discussion for it at below: > http://marc.info/?l=linux-usb&m=137996395529294&w=2 > > Signed-off-by: Peter Chen <peter.chen@freescale.com> > --- > drivers/usb/host/ehci.h | 13 +++++++++++++ > 1 files changed, 13 insertions(+), 0 deletions(-) > > diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h > index 2d40192..577b75d 100644 > --- a/drivers/usb/host/ehci.h > +++ b/drivers/usb/host/ehci.h > @@ -203,6 +203,7 @@ struct ehci_hcd { /* one per controller */ > unsigned has_synopsys_hc_bug:1; /* Synopsys HC */ > unsigned frame_index_bug:1; /* MosChip (AKA NetMos) */ > unsigned need_oc_pp_cycle:1; /* MPC834X port power */ > + unsigned imx28_write_fix:1; /* For Freescale i.MX28 */ > > /* required for usb32 quirk */ > #define OHCI_CTRL_HCFS (3 << 6) > @@ -680,6 +681,13 @@ static inline unsigned int ehci_readl(const struct ehci_hcd *ehci, > #endif > } > > +#ifdef CONFIG_SOC_IMX28 > +static inline void imx28_ehci_writel(u32 val32, volatile u32 *addr) > +{ > + __asm__ ("swp %0, %0, [%1]" : : "r"(val32), "r"(addr)); > +} > +#endif > + > static inline void ehci_writel(const struct ehci_hcd *ehci, > const unsigned int val, __u32 __iomem *regs) > { > @@ -687,6 +695,11 @@ static inline void ehci_writel(const struct ehci_hcd *ehci, > ehci_big_endian_mmio(ehci) ? > writel_be(val, regs) : > writel(val, regs); > +#elif defined(CONFIG_SOC_IMX28) > + if (ehci->imx28_write_fix) > + imx28_ehci_writel(val, regs); > + else > + writel(val, regs); Have you tested this on mx23? What if we have a kernel built for both mx23 and mx28? Regards, Fabio Estevam
On Wed, 23 Oct 2013, Peter Chen wrote: > According to Freescale imx28 Errata, "ENGR119653 USB: ARM to USB > register error issue", All USB register write operations must > use the ARM SWP instruction. So, we implement a special ehci_write > for imx28. > > Discussion for it at below: > http://marc.info/?l=linux-usb&m=137996395529294&w=2 > > Signed-off-by: Peter Chen <peter.chen@freescale.com> Acked-by: Alan Stern <stern@rowland.harvard.edu>
On Wed, Oct 23, 2013 at 10:09:39AM -0200, Fabio Estevam wrote: > Hi Peter, > > On Wed, Oct 23, 2013 at 6:35 AM, Peter Chen <peter.chen@freescale.com> wrote: > > According to Freescale imx28 Errata, "ENGR119653 USB: ARM to USB > > register error issue", All USB register write operations must > > use the ARM SWP instruction. So, we implement a special ehci_write > > for imx28. > > > > Discussion for it at below: > > http://marc.info/?l=linux-usb&m=137996395529294&w=2 > > > > Signed-off-by: Peter Chen <peter.chen@freescale.com> > > --- > > drivers/usb/host/ehci.h | 13 +++++++++++++ > > 1 files changed, 13 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h > > index 2d40192..577b75d 100644 > > --- a/drivers/usb/host/ehci.h > > +++ b/drivers/usb/host/ehci.h > > @@ -203,6 +203,7 @@ struct ehci_hcd { /* one per controller */ > > unsigned has_synopsys_hc_bug:1; /* Synopsys HC */ > > unsigned frame_index_bug:1; /* MosChip (AKA NetMos) */ > > unsigned need_oc_pp_cycle:1; /* MPC834X port power */ > > + unsigned imx28_write_fix:1; /* For Freescale i.MX28 */ > > > > /* required for usb32 quirk */ > > #define OHCI_CTRL_HCFS (3 << 6) > > @@ -680,6 +681,13 @@ static inline unsigned int ehci_readl(const struct ehci_hcd *ehci, > > #endif > > } > > > > +#ifdef CONFIG_SOC_IMX28 > > +static inline void imx28_ehci_writel(u32 val32, volatile u32 *addr) > > +{ > > + __asm__ ("swp %0, %0, [%1]" : : "r"(val32), "r"(addr)); > > +} > > +#endif > > + > > static inline void ehci_writel(const struct ehci_hcd *ehci, > > const unsigned int val, __u32 __iomem *regs) > > { > > @@ -687,6 +695,11 @@ static inline void ehci_writel(const struct ehci_hcd *ehci, > > ehci_big_endian_mmio(ehci) ? > > writel_be(val, regs) : > > writel(val, regs); > > +#elif defined(CONFIG_SOC_IMX28) > > + if (ehci->imx28_write_fix) > > + imx28_ehci_writel(val, regs); > > + else > > + writel(val, regs); > > Have you tested this on mx23? > > What if we have a kernel built for both mx23 and mx28? > The condition ehci->imx28_write_fix will only be set for imx28 platform, you can refer patch 2/3 and patch 3/3.
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h index 2d40192..577b75d 100644 --- a/drivers/usb/host/ehci.h +++ b/drivers/usb/host/ehci.h @@ -203,6 +203,7 @@ struct ehci_hcd { /* one per controller */ unsigned has_synopsys_hc_bug:1; /* Synopsys HC */ unsigned frame_index_bug:1; /* MosChip (AKA NetMos) */ unsigned need_oc_pp_cycle:1; /* MPC834X port power */ + unsigned imx28_write_fix:1; /* For Freescale i.MX28 */ /* required for usb32 quirk */ #define OHCI_CTRL_HCFS (3 << 6) @@ -680,6 +681,13 @@ static inline unsigned int ehci_readl(const struct ehci_hcd *ehci, #endif } +#ifdef CONFIG_SOC_IMX28 +static inline void imx28_ehci_writel(u32 val32, volatile u32 *addr) +{ + __asm__ ("swp %0, %0, [%1]" : : "r"(val32), "r"(addr)); +} +#endif + static inline void ehci_writel(const struct ehci_hcd *ehci, const unsigned int val, __u32 __iomem *regs) { @@ -687,6 +695,11 @@ static inline void ehci_writel(const struct ehci_hcd *ehci, ehci_big_endian_mmio(ehci) ? writel_be(val, regs) : writel(val, regs); +#elif defined(CONFIG_SOC_IMX28) + if (ehci->imx28_write_fix) + imx28_ehci_writel(val, regs); + else + writel(val, regs); #else writel(val, regs); #endif
According to Freescale imx28 Errata, "ENGR119653 USB: ARM to USB register error issue", All USB register write operations must use the ARM SWP instruction. So, we implement a special ehci_write for imx28. Discussion for it at below: http://marc.info/?l=linux-usb&m=137996395529294&w=2 Signed-off-by: Peter Chen <peter.chen@freescale.com> --- drivers/usb/host/ehci.h | 13 +++++++++++++ 1 files changed, 13 insertions(+), 0 deletions(-)