diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/host/ehci-hcd.c | 167 |
1 files changed, 138 insertions, 29 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 00a155b64d..a0ef5db43f 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -208,8 +208,8 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer, int length, struct devrequest *req) { ALLOC_ALIGN_BUFFER(struct QH, qh, 1, USB_DMA_MINALIGN); -#define QTD_COUNT 3 - ALLOC_ALIGN_BUFFER(struct qTD, qtd, QTD_COUNT, USB_DMA_MINALIGN); + struct qTD *qtd; + int qtd_count = 0; int qtd_counter = 0; volatile struct qTD *vtd; @@ -230,8 +230,74 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer, le16_to_cpu(req->value), le16_to_cpu(req->value), le16_to_cpu(req->index)); + /* + * The USB transfer is split into qTD transfers. Eeach qTD transfer is + * described by a transfer descriptor (the qTD). The qTDs form a linked + * list with a queue head (QH). + * + * Each qTD transfer starts with a new USB packet, i.e. a packet cannot + * have its beginning in a qTD transfer and its end in the following + * one, so the qTD transfer lengths have to be chosen accordingly. + * + * Each qTD transfer uses up to QT_BUFFER_CNT data buffers, mapped to + * single pages. The first data buffer can start at any offset within a + * page (not considering the cache-line alignment issues), while the + * following buffers must be page-aligned. There is no alignment + * constraint on the size of a qTD transfer. + */ + if (req != NULL) + /* 1 qTD will be needed for SETUP, and 1 for ACK. */ + qtd_count += 1 + 1; + if (length > 0 || req == NULL) { + /* + * Determine the qTD transfer size that will be used for the + * data payload (not considering the final qTD transfer, which + * may be shorter). + * + * In order to keep each packet within a qTD transfer, the qTD + * transfer size is aligned to EHCI_PAGE_SIZE, which is a + * multiple of wMaxPacketSize (except in some cases for + * interrupt transfers, see comment in submit_int_msg()). + * + * By default, i.e. if the input buffer is page-aligned, + * QT_BUFFER_CNT full pages will be used. + */ + int xfr_sz = QT_BUFFER_CNT; + /* + * However, if the input buffer is not page-aligned, the qTD + * transfer size will be one page shorter, and the first qTD + * data buffer of each transfer will be page-unaligned. + */ + if ((uint32_t)buffer & (EHCI_PAGE_SIZE - 1)) + xfr_sz--; + /* Convert the qTD transfer size to bytes. */ + xfr_sz *= EHCI_PAGE_SIZE; + /* + * Determine the number of qTDs that will be required for the + * data payload. This value has to be rounded up since the final + * qTD transfer may be shorter than the regular qTD transfer + * size that has just been computed. + */ + qtd_count += DIV_ROUND_UP(length, xfr_sz); + /* ZLPs also need a qTD. */ + if (!qtd_count) + qtd_count++; + } +/* + * Threshold value based on the worst-case total size of the qTDs to allocate + * for a mass-storage transfer of 65535 blocks of 512 bytes. + */ +#if CONFIG_SYS_MALLOC_LEN <= 128 * 1024 +#warning CONFIG_SYS_MALLOC_LEN may be too small for EHCI +#endif + qtd = memalign(USB_DMA_MINALIGN, qtd_count * sizeof(struct qTD)); + if (qtd == NULL) { + printf("unable to allocate TDs\n"); + return -1; + } + memset(qh, 0, sizeof(struct QH)); - memset(qtd, 0, QTD_COUNT * sizeof(*qtd)); + memset(qtd, 0, qtd_count * sizeof(*qtd)); toggle = usb_gettoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe)); @@ -290,30 +356,64 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer, } if (length > 0 || req == NULL) { - /* - * Setup request qTD (3.5 in ehci-r10.pdf) - * - * qt_next ................ 03-00 H - * qt_altnext ............. 07-04 H - * qt_token ............... 0B-08 H - * - * [ buffer, buffer_hi ] loaded with "buffer". - */ - qtd[qtd_counter].qt_next = cpu_to_hc32(QT_NEXT_TERMINATE); - qtd[qtd_counter].qt_altnext = cpu_to_hc32(QT_NEXT_TERMINATE); - token = QT_TOKEN_DT(toggle) | QT_TOKEN_TOTALBYTES(length) | - QT_TOKEN_IOC(req == NULL) | QT_TOKEN_CPAGE(0) | - QT_TOKEN_CERR(3) | QT_TOKEN_PID(usb_pipein(pipe) ? - QT_TOKEN_PID_IN : QT_TOKEN_PID_OUT) | - QT_TOKEN_STATUS(QT_TOKEN_STATUS_ACTIVE); - qtd[qtd_counter].qt_token = cpu_to_hc32(token); - if (ehci_td_buffer(&qtd[qtd_counter], buffer, length)) { - printf("unable to construct DATA TD\n"); - goto fail; - } - /* Update previous qTD! */ - *tdp = cpu_to_hc32((uint32_t)&qtd[qtd_counter]); - tdp = &qtd[qtd_counter++].qt_next; + uint8_t *buf_ptr = buffer; + int left_length = length; + + do { + /* + * Determine the size of this qTD transfer. By default, + * QT_BUFFER_CNT full pages can be used. + */ + int xfr_bytes = QT_BUFFER_CNT * EHCI_PAGE_SIZE; + /* + * However, if the input buffer is not page-aligned, the + * portion of the first page before the buffer start + * offset within that page is unusable. + */ + xfr_bytes -= (uint32_t)buf_ptr & (EHCI_PAGE_SIZE - 1); + /* + * In order to keep each packet within a qTD transfer, + * align the qTD transfer size to EHCI_PAGE_SIZE. + */ + xfr_bytes &= ~(EHCI_PAGE_SIZE - 1); + /* + * This transfer may be shorter than the available qTD + * transfer size that has just been computed. + */ + xfr_bytes = min(xfr_bytes, left_length); + + /* + * Setup request qTD (3.5 in ehci-r10.pdf) + * + * qt_next ................ 03-00 H + * qt_altnext ............. 07-04 H + * qt_token ............... 0B-08 H + * + * [ buffer, buffer_hi ] loaded with "buffer". + */ + qtd[qtd_counter].qt_next = + cpu_to_hc32(QT_NEXT_TERMINATE); + qtd[qtd_counter].qt_altnext = + cpu_to_hc32(QT_NEXT_TERMINATE); + token = QT_TOKEN_DT(toggle) | + QT_TOKEN_TOTALBYTES(xfr_bytes) | + QT_TOKEN_IOC(req == NULL) | QT_TOKEN_CPAGE(0) | + QT_TOKEN_CERR(3) | + QT_TOKEN_PID(usb_pipein(pipe) ? + QT_TOKEN_PID_IN : QT_TOKEN_PID_OUT) | + QT_TOKEN_STATUS(QT_TOKEN_STATUS_ACTIVE); + qtd[qtd_counter].qt_token = cpu_to_hc32(token); + if (ehci_td_buffer(&qtd[qtd_counter], buf_ptr, + xfr_bytes)) { + printf("unable to construct DATA TD\n"); + goto fail; + } + /* Update previous qTD! */ + *tdp = cpu_to_hc32((uint32_t)&qtd[qtd_counter]); + tdp = &qtd[qtd_counter++].qt_next; + buf_ptr += xfr_bytes; + left_length -= xfr_bytes; + } while (left_length > 0); } if (req != NULL) { @@ -344,7 +444,7 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer, ALIGN_END_ADDR(struct QH, qh_list, 1)); flush_dcache_range((uint32_t)qh, ALIGN_END_ADDR(struct QH, qh, 1)); flush_dcache_range((uint32_t)qtd, - ALIGN_END_ADDR(struct qTD, qtd, QTD_COUNT)); + ALIGN_END_ADDR(struct qTD, qtd, qtd_count)); /* Set async. queue head pointer. */ ehci_writel(&hcor->or_asynclistaddr, (uint32_t)qh_list); @@ -375,7 +475,7 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer, invalidate_dcache_range((uint32_t)qh, ALIGN_END_ADDR(struct QH, qh, 1)); invalidate_dcache_range((uint32_t)qtd, - ALIGN_END_ADDR(struct qTD, qtd, QTD_COUNT)); + ALIGN_END_ADDR(struct qTD, qtd, qtd_count)); token = hc32_to_cpu(vtd->qt_token); if (!(QT_TOKEN_GET_STATUS(token) & QT_TOKEN_STATUS_ACTIVE)) @@ -448,9 +548,11 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer, ehci_readl(&hcor->or_portsc[1])); } + free(qtd); return (dev->status != USB_ST_NOT_PROC) ? 0 : -1; fail: + free(qtd); return -1; } @@ -827,6 +929,13 @@ submit_int_msg(struct usb_device *dev, unsigned long pipe, void *buffer, /* * Interrupt transfers requiring several transactions are not supported * because bInterval is ignored. + * + * Also, ehci_submit_async() relies on wMaxPacketSize being a power of 2 + * if several qTDs are required, while the USB specification does not + * constrain this for interrupt transfers. That means that + * ehci_submit_async() would support interrupt transfers requiring + * several transactions only as long as the transfer size does not + * require more than a single qTD. */ if (length > usb_maxpacket(dev, pipe)) { printf("%s: Interrupt transfers requiring several transactions " |
