From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rajesh Bhagat Date: Tue, 31 May 2016 03:23:33 +0000 Subject: [U-Boot] [PATCH 1/2] common: usb_storage : Implement logic to calculate optimal usb maximum trasfer blocks In-Reply-To: <574CCFBE.3020808@denx.de> References: <1464607435-2639-1-git-send-email-rajesh.bhagat@nxp.com> <1464607435-2639-2-git-send-email-rajesh.bhagat@nxp.com> <574CCFBE.3020808@denx.de> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de > -----Original Message----- > From: Marek Vasut [mailto:marex at denx.de] > Sent: Tuesday, May 31, 2016 5:12 AM > To: Rajesh Bhagat ; u-boot at lists.denx.de > Cc: sjg at chromium.org; york sun ; Sriram Dash > > Subject: Re: [PATCH 1/2] common: usb_storage : Implement logic to calculate > optimal usb maximum trasfer blocks > > On 05/30/2016 01:23 PM, 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 adds an array of 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 andmax = 65535 is > > taken. And for other cases code is left unchanged by keeping min = max > > = 20. > > > > Signed-off-by: Sriram Dash > > Signed-off-by: Rajesh Bhagat > > --- > > common/usb_storage.c | 54 > ++++++++++++++++++++++++++++++++++++++++---------- > > 1 file changed, 43 insertions(+), 11 deletions(-) > > > > diff --git a/common/usb_storage.c b/common/usb_storage.c index > > 7e6e52d..7b5ad07 100644 > > --- a/common/usb_storage.c > > +++ b/common/usb_storage.c > > @@ -101,16 +101,15 @@ struct us_data { }; > > > > #ifdef CONFIG_USB_EHCI > > -/* > > - * The U-Boot EHCI driver can handle any transfer length as long as > > there is > > - * enough free heap space left, but the SCSI READ(10) and WRITE(10) > > commands are > > - * limited to 65535 blocks. > > - */ > > -#define USB_MAX_XFER_BLK 65535 > > +#define USB_XFER_BLK_TBL_SZ 5 > > +static unsigned short usb_xfer_blk_tbl[5] = {4096, 8192, 16384, > > +32768, 65535}; > > You should stick to using one block less than the power of two, the controllers react to > that a bit better. Hello Marek, I agree to above point, Will change the logic to use one block less than power of two i.e. 4095, 8191... 65535 > Each value in this table can then be calculated really trivially, it's: > > (1 << (12 + n)) - 1 > Prior to current implementation, I created USB_MIN_XFER_BLK=4096 and USB_MAX_XFER_BLK=65535 macros. And started the logic to multiple and divide by two to reach USB_MAX_XFER_BLK. Then thought, calculation would be costlier than indexing an array. Please comment. > You also don't need such static data. > Let me share the background for keeping this variable, It is taken to store the last optimal value for next read/write operation. And these value is reset to minimum when another USB device is connected. Refer below log: 1st time (Iterated over all the possible size) => mw 81000000 55555555 4000000; mw a0000000 aaaaaaaa 4000000; usb write a0000000 0 80000; usb read 81000000 0 80000; cmp.b a0000000 81000000 10000000; USB write: device 0 block # 0, count 524288 ... usb_read: retry #2, xfer_blk 4096, smallblks 4096 usb_read: retry #2, xfer_blk 8192, smallblks 8192 usb_read: retry #2, xfer_blk 16384, smallblks 16384 usb_read: retry #2, xfer_blk 32768, smallblks 32768 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 4103 524288 blocks write: OK 2nd time (It started form 65535 blocks as it is last optimal value) => mw 81000000 55555555 4000000; mw a0000000 aaaaaaaa 4000000; usb write a0000000 0 80000; usb read 81000000 0 80000; cmp.b a0000000 81000000 10000000; USB write: device 0 block # 0, count 524288 ... usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 65535 usb_read: retry #2, xfer_blk 65535, smallblks 8 524288 blocks write: OK And I observed this value is different for read/write, Hence second patch is sent for handle that situation. Best Regards, Rajesh Bhagat > > #else > > -#define USB_MAX_XFER_BLK 20 > > +#define USB_XFER_BLK_TBL_SZ 1 > > +static unsigned short usb_xfer_blk_tbl[1] = {20}; > > #endif > > > > +static unsigned short USB_MAX_XFER_BLK; > > This value is different on per-device basis, how can it be static data ? > > > #ifndef CONFIG_BLK > > static struct us_data usb_stor[USB_MAX_STOR_DEV]; #endif @@ -1117,7 > > +1116,8 @@ 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, next = LOG2((USB_MAX_XFER_BLK + 1) / usb_xfer_blk_tbl[0]); > > + bool retry_flag = false; > > ccb *srb = &usb_ccb; > > #ifdef CONFIG_BLK > > struct blk_desc *block_dev; > > @@ -1158,6 +1158,8 @@ static unsigned long usb_stor_read(struct blk_desc > *block_dev, lbaint_t blknr, > > else > > smallblks = (unsigned short) blks; > > retry_it: > > + debug("usb_read: retry #%d, xfer_blk %hu, smallblks %hu\n", > > + retry, USB_MAX_XFER_BLK, smallblks); > > if (smallblks == USB_MAX_XFER_BLK) > > usb_show_progress(); > > srb->datalen = block_dev->blksz * smallblks; @@ -1165,14 +1167,26 > > @@ retry_it: > > if (usb_read_10(srb, ss, start, smallblks)) { > > debug("Read ERROR\n"); > > usb_request_sense(srb, ss); > > - if (retry--) > > + if (retry--) { > > + /* decrease the USB_MAX_XFER_BLK */ > > + if (next > 0) { > > + smallblks = usb_xfer_blk_tbl[--next]; > > + USB_MAX_XFER_BLK = smallblks; > > + } > > + retry_flag = true; > > goto retry_it; > > + } > > blkcnt -= blks; > > break; > > } > > start += smallblks; > > blks -= smallblks; > > buf_addr += srb->datalen; > > + > > + /* try to increase the USB_MAX_XFER_BLK */ > > + if (next < USB_XFER_BLK_TBL_SZ - 1) > > + if (!retry_flag && usb_xfer_blk_tbl[next + 1] <= blks) > > + USB_MAX_XFER_BLK = usb_xfer_blk_tbl[++next]; > > } while (blks != 0); > > ss->flags &= ~USB_READY; > > > > @@ -1199,7 +1213,8 @@ 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, next = LOG2((USB_MAX_XFER_BLK + 1) / usb_xfer_blk_tbl[0]); > > + bool retry_flag = false; > > ccb *srb = &usb_ccb; > > #ifdef CONFIG_BLK > > struct blk_desc *block_dev; > > @@ -1244,6 +1259,8 @@ static unsigned long usb_stor_write(struct blk_desc > *block_dev, lbaint_t blknr, > > else > > smallblks = (unsigned short) blks; > > retry_it: > > + debug("usb_write: retry #%d, xfer_blk %hu, smallblks %hu\n", > > + retry, USB_MAX_XFER_BLK, smallblks); > > if (smallblks == USB_MAX_XFER_BLK) > > usb_show_progress(); > > srb->datalen = block_dev->blksz * smallblks; @@ -1251,14 +1268,26 > > @@ retry_it: > > if (usb_write_10(srb, ss, start, smallblks)) { > > debug("Write ERROR\n"); > > usb_request_sense(srb, ss); > > - if (retry--) > > + if (retry--) { > > + /* decrease the USB_MAX_XFER_BLK */ > > + if (next > 0) { > > + smallblks = usb_xfer_blk_tbl[--next]; > > + USB_MAX_XFER_BLK = smallblks; > > + } > > + retry_flag = true; > > goto retry_it; > > + } > > blkcnt -= blks; > > break; > > } > > start += smallblks; > > blks -= smallblks; > > buf_addr += srb->datalen; > > + > > + /* try to increase the USB_MAX_XFER_BLK */ > > + if (next < USB_XFER_BLK_TBL_SZ - 1) > > + if (!retry_flag && usb_xfer_blk_tbl[next + 1] <= blks) > > + USB_MAX_XFER_BLK = usb_xfer_blk_tbl[++next]; > > } while (blks != 0); > > ss->flags &= ~USB_READY; > > > > @@ -1331,6 +1360,9 @@ int usb_storage_probe(struct usb_device *dev, unsigned > int ifnum, > > break; > > } > > > > + /* Initialize the current transfer blocks to minimum value */ > > + USB_MAX_XFER_BLK = usb_xfer_blk_tbl[0]; > > + > > /* > > * We are expecting a minimum of 2 endpoints - in and out (bulk). > > * An optional interrupt is OK (necessary for CBI protocol). > > > > > -- > Best regards, > Marek Vasut