[U-Boot] [PATCH v4] usb: align buffers at cacheline

Marek Vasut
2012-03-02T13:46:24Z

> As DMA expects the buffers to be equal and larger then
> cache lines, This aligns buffers at cacheline.
>
> Signed-off-by: Puneet Saxena <puneets@nvidia.com>
> ---
>
> Changes for V3:
> - Removed local descriptor elements copy to global descriptor elements
> - Removed "Signed-off-by: Jim Lin <jilin@nvidia.com>" from commit
> message
>
> Changes for V4:
> - Added memcpy to copy local descriptor to global descriptor.
> Without that, USB version, class, vendor, product Id...etc is not
> configured. This information is useful for loading correct device driver
> and possible configuration.
>
>
> common/cmd_usb.c | 3 +-
> common/usb.c | 56
> ++++++++++++++++++++++------------------ common/usb_storage.c |
> 59 ++++++++++++++++++++---------------------- disk/part_dos.c
> | 2 +-
> drivers/usb/host/ehci-hcd.c | 8 ++++++
> include/scsi.h | 4 ++-
> 6 files changed, 73 insertions(+), 59 deletions(-)
>
> diff --git a/common/cmd_usb.c b/common/cmd_usb.c
> index 320667f..bca9d94 100644
> --- a/common/cmd_usb.c
> +++ b/common/cmd_usb.c
> @@ -150,7 +150,8 @@ void usb_display_class_sub(unsigned char dclass,
> unsigned char subclass,
>
> void usb_display_string(struct usb_device *dev, int index)
> {
> - char buffer[256];
> + ALLOC_CACHE_ALIGN_BUFFER(char, buffer, 256);
> +
> if (index != 0) {
> if (usb_string(dev, index, &buffer[0], 256) > 0)
> printf("String: \"%s\"", buffer);
> diff --git a/common/usb.c b/common/usb.c
> index 6e21ae2..42a44e2 100644
> --- a/common/usb.c
> +++ b/common/usb.c
> @@ -73,7 +73,6 @@ static struct usb_device usb_dev[USB_MAX_DEVICE];
> static int dev_index;
> static int running;
> static int asynch_allowed;
> -static struct devrequest setup_packet;
>
> char usb_started; /* flag for the started/stopped USB status */
>
> @@ -185,23 +184,25 @@ int usb_control_msg(struct usb_device *dev, unsigned
> int pipe, unsigned short value, unsigned short index,
> void *data, unsigned short size, int timeout)
> {
> + ALLOC_CACHE_ALIGN_BUFFER(struct devrequest, setup_packet,
> + sizeof(struct devrequest));
> if ((timeout == 0) && (!asynch_allowed)) {
> /* request for a asynch control pipe is not allowed */
> return -1;
> }
>
> /* set setup command */
> - setup_packet.requesttype = requesttype;
> - setup_packet.request = request;
> - setup_packet.value = cpu_to_le16(value);
> - setup_packet.index = cpu_to_le16(index);
> - setup_packet.length = cpu_to_le16(size);
> + setup_packet->requesttype = requesttype;
> + setup_packet->request = request;
> + setup_packet->value = cpu_to_le16(value);
> + setup_packet->index = cpu_to_le16(index);
> + setup_packet->length = cpu_to_le16(size);
> USB_PRINTF("usb_control_msg: request: 0x%X, requesttype: 0x%X, " \
> "value 0x%X index 0x%X length 0x%X\n",
> request, requesttype, value, index, size);
> dev->status = USB_ST_NOT_PROC; /*not yet processed */
>
> - submit_control_msg(dev, pipe, data, size, &setup_packet);
> + submit_control_msg(dev, pipe, data, size, setup_packet);
> if (timeout == 0)
> return (int)size;
>
> @@ -698,7 +699,7 @@ static int usb_string_sub(struct usb_device *dev,
> unsigned int langid, */
> int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
> {
> - unsigned char mybuf[USB_BUFSIZ];
> + ALLOC_CACHE_ALIGN_BUFFER(unsigned char, mybuf, USB_BUFSIZ);
> unsigned char *tbuf;
> int err;
> unsigned int u, idx;
> @@ -798,7 +799,7 @@ int usb_new_device(struct usb_device *dev)
> {
> int addr, err;
> int tmp;
> - unsigned char tmpbuf[USB_BUFSIZ];
> + ALLOC_CACHE_ALIGN_BUFFER(unsigned char, tmpbuf, USB_BUFSIZ);
>
> /* We still haven't set the Address yet */
> addr = dev->devnum;
> @@ -909,7 +910,7 @@ int usb_new_device(struct usb_device *dev)
> tmp = sizeof(dev->descriptor);
>
> err = usb_get_descriptor(dev, USB_DT_DEVICE, 0,
> - &dev->descriptor, sizeof(dev->descriptor));
> + desc, sizeof(dev->descriptor));
> if (err < tmp) {
> if (err < 0)
> printf("unable to get device descriptor (error=%d)\n",
> @@ -919,14 +920,18 @@ int usb_new_device(struct usb_device *dev)
> "(expected %i, got %i)\n", tmp, err);
> return 1;
> }
> +
> + /* Now copy the local device descriptor to global device descriptor*/
> + memcpy(&dev->descriptor, desc, sizeof(dev->descriptor));

Hey, it's almost perfect!

Just one last question -- why do you need to copy this stuff? It's because dev-
>descriptor is unaligned?

M