On 06/08/2016 06:09 AM, Rajesh Bhagat wrote: > > >> -----Original Message----- >> From: Marek Vasut [mailto:ma...@denx.de] >> Sent: Wednesday, June 08, 2016 8:38 AM >> To: Rajesh Bhagat <rajesh.bha...@nxp.com>; u-boot@lists.denx.de >> Cc: s...@chromium.org; york sun <york....@nxp.com>; Sriram Dash >> <sriram.d...@nxp.com> >> Subject: Re: [PATCH v3] common: usb_storage : Implement logic to calculate >> optimal >> usb maximum trasfer blocks >> >> On 06/07/2016 11:29 AM, Rajesh Bhagat wrote: >>> Implements the logic to calculate the optimal usb maximum trasfer >>> blocks instead of sending USB_MAX_XFER_BLK blocks which is 65535 and >>> 20 in case of EHCI and other USB protocols respectively. >>> >>> It defines USB_MIN_XFER_BLK/USB_MAX_XFER_BLK trasfer blocks that >>> should be checked for success starting from minimum to maximum, and >>> rest of the read/write are performed with that optimal value. It tries >>> to increase/ decrease the blocks in follwing scenarios: >>> >>> 1.decrease blocks: when read/write for a particular number of blocks >>> fails. >>> 2. increase blocks: when read/write for a particular number of blocks >>> pass and amount left to trasfer is greater than current number of >>> blocks. >>> >>> Currently changes are done for EHCI where min = 4096 and max = 65535 >>> is taken. And for other cases code is left unchanged by keeping min = >>> max = 20. >>> >>> Signed-off-by: Sriram Dash <sriram.d...@nxp.com> >>> Signed-off-by: Rajesh Bhagat <rajesh.bha...@nxp.com> >>> --- >>> Changes in v3: >>> - Adds cur_xfer_blks in struct usb_device to retain values >>> - Adds functions dec/inc_cur_xfer_blks to remove code duplication >>> - Moves check from macro to calling functions >>> >>> Changes in v2: >>> - Removes table to store blocks and use formula (1 << (12 + n)) - 1 >>> - Adds logic to start from minimum, go to maximum in each read/write >>> >>> common/usb_storage.c | 78 >> ++++++++++++++++++++++++++++++++++++++++++++-------- >>> include/usb.h | 1 + >>> 2 files changed, 67 insertions(+), 12 deletions(-) >>> >>> diff --git a/common/usb_storage.c b/common/usb_storage.c index >>> 7e6e52d..e08dcd4 100644 >>> --- a/common/usb_storage.c >>> +++ b/common/usb_storage.c >>> @@ -106,11 +106,40 @@ struct us_data { >>> * enough free heap space left, but the SCSI READ(10) and WRITE(10) >>> commands >> are >>> * limited to 65535 blocks. >>> */ >>> +#define USB_MIN_XFER_BLK 4095 >>> #define USB_MAX_XFER_BLK 65535 >>> #else >>> +#define USB_MIN_XFER_BLK 20 >>> #define USB_MAX_XFER_BLK 20 >>> #endif >>> >>> +#define GET_CUR_XFER_BLKS(blks) (LOG2(blks / (USB_MIN_XFER_BLK + >> 1))) >>> +#define CALC_CUR_XFER_BLKS(pos) ((1 << (12 + pos)) - 1) >>> + >>> +static int dec_cur_xfer_blks(int *pos, unsigned short *smallblks) { >>> + /* decrease the cur_xfer_blks */ >>> + unsigned short size = (*pos > 0) ? CALC_CUR_XFER_BLKS(*pos - 1) : 0; >> > > Hello Marek, > >> If someone passes null pointer into the function, it will fail. >> Also, you can refactor it to make it more readable: >> >> if (!pos) >> return -EINVAL; >> if (size < USB_MIN_XFER_BLK) >> return -EINVAL; >> ... do stuff ... >> > > Refactoring the code to return early in case of error conditions is fine. But > pos and smallblks can never be passed as NULL in these functions.
... until an idiot comes around and does it. >> I still don't understand why $pos isn't unsigned int, it should be. >> > > I believe keeping a variable as "int" provides a natural way of checking for > overflow conditions. We check can check if number has become negative and > take > actions, which is not possible when number is taken as "unsigned int". But the number here can never be negative, can it ? >>> + if (size >= USB_MIN_XFER_BLK) { >>> + *smallblks = size; >>> + (*pos)--; >>> + return 0; >>> + } >>> + return -EINVAL; >>> +} >>> + >>> +static int inc_cur_xfer_blks(int *pos, unsigned short *smallblks, >>> +lbaint_t blks) { >>> + /* try to increase the cur_xfer_blks */ >>> + unsigned short size = (*pos >= 0) ? CALC_CUR_XFER_BLKS(*pos + 1) : 0; >>> + if (size <= blks && size <= USB_MAX_XFER_BLK) { >>> + *smallblks = size; >>> + (*pos)++; >>> + return 0; >>> + } >>> + return -EINVAL; >>> +} >>> + >>> #ifndef CONFIG_BLK >>> static struct us_data usb_stor[USB_MAX_STOR_DEV]; #endif @@ -1117,7 >>> +1146,8 @@ static unsigned long usb_stor_read(struct blk_desc *block_dev, >> lbaint_t blknr, >>> unsigned short smallblks; >>> struct usb_device *udev; >>> struct us_data *ss; >>> - int retry; >>> + int retry, pos; >>> + bool retry_flag = false; >>> ccb *srb = &usb_ccb; >>> #ifdef CONFIG_BLK >>> struct blk_desc *block_dev; >>> @@ -1145,6 +1175,7 @@ static unsigned long usb_stor_read(struct blk_desc >> *block_dev, lbaint_t blknr, >>> buf_addr = (uintptr_t)buffer; >>> start = blknr; >>> blks = blkcnt; >>> + pos = GET_CUR_XFER_BLKS(udev->cur_xfer_blks); >> >> Is this $pos even needed ? Why ? > > $pos variable is updated in dec/inc_cur_xfer_blks functions which calculates > the > next transfer blocks, and finally when all conditions are met is stored in > udev->cur_xfer_blks. And why doesn't this work with udev->cur_xfer_blks directly ? >> >>> debug("\nusb_read: dev %d startblk " LBAF ", blccnt " LBAF " buffer %" >>> PRIxPTR "\n", block_dev->devnum, start, blks, buf_addr); @@ >>> -1153,26 +1184,35 @@ static unsigned long usb_stor_read(struct blk_desc >> *block_dev, lbaint_t blknr, >>> /* XXX need some comment here */ >>> retry = 2; >>> srb->pdata = (unsigned char *)buf_addr; >>> - if (blks > USB_MAX_XFER_BLK) >>> - smallblks = USB_MAX_XFER_BLK; >>> + if (blks > udev->cur_xfer_blks) >>> + smallblks = udev->cur_xfer_blks; >>> else >>> smallblks = (unsigned short) blks; >>> retry_it: >>> - if (smallblks == USB_MAX_XFER_BLK) >>> + debug("usb_read: retry #%d, cur_xfer_blks %hu, smallblks %hu\n", >>> + retry, udev->cur_xfer_blks, smallblks); >>> + if (smallblks == udev->cur_xfer_blks) >>> usb_show_progress(); >>> srb->datalen = block_dev->blksz * smallblks; >>> srb->pdata = (unsigned char *)buf_addr; >>> if (usb_read_10(srb, ss, start, smallblks)) { >>> debug("Read ERROR\n"); >>> usb_request_sense(srb, ss); >>> - if (retry--) >>> + if (retry--) { >>> + if (!dec_cur_xfer_blks(&pos, &smallblks)) >>> + udev->cur_xfer_blks = smallblks; >>> + retry_flag = true; >>> goto retry_it; >>> + } >>> blkcnt -= blks; >> >> The same piece of code is below. I would rather see you factor out the >> common code >> and then make any changes. >> > > IMHO, All the common code is moved in functions dec/inc_cur_xfer_blks as > pointed earlier. > Are you are referring to other common code of usb_stor_read/write functions > which is not > part of this patchset. If yes, I would prefer to take it as a next patch set. Please don't add new stuff to code which needs fixing first, that's not a good practice. Prepare the ground first and then add new stuff. > Best Regards, > Rajesh Bhagat > >>> break; >>> } >>> start += smallblks; >>> blks -= smallblks; >>> buf_addr += srb->datalen; >>> + >>> + if (!retry_flag && !inc_cur_xfer_blks(&pos, &smallblks, blks)) >>> + udev->cur_xfer_blks = smallblks; >>> } while (blks != 0); >>> ss->flags &= ~USB_READY; >>> >>> @@ -1181,7 +1221,7 @@ retry_it: >>> start, smallblks, buf_addr); >>> >>> usb_disable_asynch(0); /* asynch transfer allowed */ >>> - if (blkcnt >= USB_MAX_XFER_BLK) >>> + if (blkcnt >= udev->cur_xfer_blks) >>> debug("\n"); >>> return blkcnt; >>> } >>> @@ -1199,7 +1239,8 @@ static unsigned long usb_stor_write(struct blk_desc >> *block_dev, lbaint_t blknr, >>> unsigned short smallblks; >>> struct usb_device *udev; >>> struct us_data *ss; >>> - int retry; >>> + int retry, pos; >>> + bool retry_flag = false; >>> ccb *srb = &usb_ccb; >>> #ifdef CONFIG_BLK >>> struct blk_desc *block_dev; >>> @@ -1222,6 +1263,7 @@ static unsigned long usb_stor_write(struct blk_desc >> *block_dev, lbaint_t blknr, >>> } >>> #endif >>> ss = (struct us_data *)udev->privptr; >>> + pos = GET_CUR_XFER_BLKS(udev->cur_xfer_blks); >>> >>> usb_disable_asynch(1); /* asynch transfer not allowed */ >>> >>> @@ -1239,26 +1281,35 @@ static unsigned long usb_stor_write(struct blk_desc >> *block_dev, lbaint_t blknr, >>> */ >>> retry = 2; >>> srb->pdata = (unsigned char *)buf_addr; >>> - if (blks > USB_MAX_XFER_BLK) >>> - smallblks = USB_MAX_XFER_BLK; >>> + if (blks > udev->cur_xfer_blks) >>> + smallblks = udev->cur_xfer_blks; >>> else >>> smallblks = (unsigned short) blks; >>> retry_it: >>> - if (smallblks == USB_MAX_XFER_BLK) >>> + debug("usb_write: retry #%d, cur_xfer_blks %hu, smallblks >>> %hu\n", >>> + retry, udev->cur_xfer_blks, smallblks); >>> + if (smallblks == udev->cur_xfer_blks) >>> usb_show_progress(); >>> srb->datalen = block_dev->blksz * smallblks; >>> srb->pdata = (unsigned char *)buf_addr; >>> if (usb_write_10(srb, ss, start, smallblks)) { >>> debug("Write ERROR\n"); >>> usb_request_sense(srb, ss); >>> - if (retry--) >>> + if (retry--) { >>> + if (!dec_cur_xfer_blks(&pos, &smallblks)) >>> + udev->cur_xfer_blks = smallblks; >>> + retry_flag = true; >>> goto retry_it; >>> + } >>> blkcnt -= blks; >>> break; >>> } >>> start += smallblks; >>> blks -= smallblks; >>> buf_addr += srb->datalen; >>> + >>> + if (!retry_flag && !inc_cur_xfer_blks(&pos, &smallblks, blks)) >>> + udev->cur_xfer_blks = smallblks; >>> } while (blks != 0); >>> ss->flags &= ~USB_READY; >>> >>> @@ -1266,7 +1317,7 @@ retry_it: >>> PRIxPTR "\n", start, smallblks, buf_addr); >>> >>> usb_disable_asynch(0); /* asynch transfer allowed */ >>> - if (blkcnt >= USB_MAX_XFER_BLK) >>> + if (blkcnt >= udev->cur_xfer_blks) >>> debug("\n"); >>> return blkcnt; >>> >>> @@ -1331,6 +1382,9 @@ int usb_storage_probe(struct usb_device *dev, unsigned >> int ifnum, >>> break; >>> } >>> >>> + /* Initialize the current transfer blocks to minimum value */ >>> + dev->cur_xfer_blks = USB_MIN_XFER_BLK; >>> + >>> /* >>> * We are expecting a minimum of 2 endpoints - in and out (bulk). >>> * An optional interrupt is OK (necessary for CBI protocol). >>> diff --git a/include/usb.h b/include/usb.h index 02a0ccd..bd49014 >>> 100644 >>> --- a/include/usb.h >>> +++ b/include/usb.h >>> @@ -153,6 +153,7 @@ struct usb_device { >>> struct udevice *dev; /* Pointer to associated device */ >>> struct udevice *controller_dev; /* Pointer to associated controller */ >>> #endif >>> + unsigned short cur_xfer_blks; /* Current maximum transfer blocks */ >>> }; >>> >>> struct int_queue; >>> >> >> >> -- >> Best regards, >> Marek Vasut -- Best regards, Marek Vasut _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot