[U-Boot] [PATCH 3/4] ehci-hcd.c: Add a new USB_DMA_MINALIGN define for cache alignment

[Marek Vasut]

Dear Tom Rini,

> The USB spec says that 32 bytes is the minimum required alignment.
> However on some platforms we have a larger minimum requirement for cache
> coherency.  In those cases, use that value rather than the USB spec
> minimum.
> 
> Cc: Marek Vasut <marex at denx.de>
> Signed-off-by: Tom Rini <trini at ti.com>
> ---
>  drivers/usb/host/ehci-hcd.c |   23 +++++++++++++++++------
>  1 file changed, 17 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
> index 04300be..45725f5 100644
> --- a/drivers/usb/host/ehci-hcd.c
> +++ b/drivers/usb/host/ehci-hcd.c
> @@ -29,12 +29,23 @@
> 
>  #include "ehci.h"
> 
> -int rootdev;
> -struct ehci_hccr *hccr;	/* R/O registers, not need for volatile */
> -volatile struct ehci_hcor *hcor;
> +/*
> + * The EHCI spec says that we must align to at least 32 bytes.  However,
> + * some platforms require larger alignment.
> + */
> +#if ARCH_DMA_MINALIGN > 32
> +#define USB_DMA_MINALIGN	ARCH_DMA_MINALIGN
> +#else
> +#define USB_DMA_MINALIGN	32
> +#endif

Don't we have some common header for these?

> +
> +int rootdev __attribute__((aligned(USB_DMA_MINALIGN)));
> +/* R/O registers, not need for volatile */
> +struct ehci_hccr *hccr __attribute__((aligned(USB_DMA_MINALIGN)));
> +volatile struct ehci_hcor *hcor
> __attribute__((aligned(USB_DMA_MINALIGN)));
> 
>  static uint16_t portreset;
> -static struct QH qh_list __attribute__((aligned(32)));
> +static struct QH qh_list __attribute__((aligned(USB_DMA_MINALIGN)));
> 
>  static struct descriptor {
>  	struct usb_hub_descriptor hub;
> @@ -207,8 +218,8 @@ static int
>  ehci_submit_async(struct usb_device *dev, unsigned long pipe, void
> *buffer, int length, struct devrequest *req)
>  {
> -	static struct QH qh __attribute__((aligned(32)));
> -	static struct qTD qtd[3] __attribute__((aligned (32)));
> +	static struct QH qh __attribute__((aligned(USB_DMA_MINALIGN)));
> +	static struct qTD qtd[3] __attribute__((aligned(USB_DMA_MINALIGN)));
>  	int qtd_counter = 0;
> 
>  	volatile struct qTD *vtd;

Best regards,
Marek Vasut