Re: [PATCH v3 11/17] hw/usb/hcd-ehci: Implement 64-bit iTD descriptor addressing

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 16/4/26 03:49, Jamin Lin wrote:
> EHCI supports 64-bit control data structure addressing when the
> 64-bit Addressing Capability bit in HCCPARAMS is set. In that mode,
> the CTRLDSSEGMENT register provides the upper 32 bits that are
> concatenated with 32-bit link pointer values to form full 64-bit
> descriptor addresses (EHCI 1.0, section 2.3.5 and Appendix B).
> 
> iTD link pointers are stored as 32-bit values and must be expanded
> to full 64-bit descriptor addresses when 64-bit mode is enabled.
> Update the iTD traversal path to use ehci_get_desc_addr() when
> following link pointers.
> 
> Appendix B also defines high dword fields for iTD buffer pointers.
> Add bufptr_hi[7] to EHCIitd and use ehci_get_buf_addr() to construct
> full 64-bit buffer addresses from bufptr[] and bufptr_hi[] fields
> when processing isochronous transfers. This allows buffers above
> 4GB to be handled correctly.
> 
> When 64-bit capability is disabled, descriptor and buffer addresses
> remain 32-bit and existing behaviour is unchanged.
> 
> Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
> ---
>   hw/usb/hcd-ehci.h | 1 +
>   hw/usb/hcd-ehci.c | 9 ++++++---
>   2 files changed, 7 insertions(+), 3 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>