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>
Reviewed-by: Simon Glass <s...@chromium.org>
---
Changes in v7:
- None
Changes in v6:
- Adds paranthesis around macro variables
- Removes extra ternary operator from dec_cur_xfer_blks
- Clamps the size to min(blks, USB_MAX_XFER_BLK) in inc_cur_xfer_blks
Changes in v5:
- None
Changes in v4:
- Adds udev paramater in dec/inc_cur_xfer_blks function and adds
sanity check on it.
- Changes type of pos varible to unsigned int in dec/inc_cur_xfer_blks
- Removes usage of pos varible from usb_stor_read/write
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 | 66 ++++++++++++++++++++++++++++++++++++++++++++++++----
include/usb.h | 1 +
2 files changed, 62 insertions(+), 5 deletions(-)
diff --git a/common/usb_storage.c b/common/usb_storage.c
index a7d84bf..93b901c 100644
--- a/common/usb_storage.c
+++ b/common/usb_storage.c
@@ -106,11 +106,16 @@ 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) + 1) / (USB_MIN_XFER_BLK
+ 1)))
+#define CALC_CUR_XFER_BLKS(pos) ((1 << (12 + (pos))) - 1)
+
#ifndef CONFIG_BLK
static struct us_data usb_stor[USB_MAX_STOR_DEV];
#endif
@@ -141,6 +146,44 @@ static void usb_show_progress(void)
debug(".");
}
+static int dec_cur_xfer_blks(struct usb_device *udev)
+{
+ /* decrease the cur_xfer_blks */
+ unsigned int pos;
+ unsigned short size;
+
+ if (!udev)
+ return -EINVAL;
+
+ pos = GET_CUR_XFER_BLKS(udev->cur_xfer_blks);
+ size = CALC_CUR_XFER_BLKS(pos - 1);
+
+ if (size < USB_MIN_XFER_BLK)
+ return -EINVAL;
+
+ udev->cur_xfer_blks = size;
+ return 0;
+}
+
+static int inc_cur_xfer_blks(struct usb_device *udev, lbaint_t blks)
+{
+ /* try to increase the cur_xfer_blks */
+ unsigned int pos;
+ unsigned short size;
+
+ if (!udev)
+ return -EINVAL;
+
+ pos = GET_CUR_XFER_BLKS(udev->cur_xfer_blks);
+ size = CALC_CUR_XFER_BLKS(pos + 1);
+
+ if (size > min(blks, (lbaint_t)USB_MAX_XFER_BLK))
+ return -EINVAL;
+
+ udev->cur_xfer_blks = size;
+ return 0;
+}
+
/*******************************************************************************
* show info on storage devices; 'usb start/init' must be invoked earlier
* as we only retrieve structures populated during devices initialization
@@ -1102,6 +1145,7 @@ static unsigned long usb_stor_read_write(struct blk_desc
*block_dev,
struct usb_device *udev;
struct us_data *ss;
int retry;
+ bool retry_flag = false;
ccb *srb = &usb_ccb;
#ifdef CONFIG_BLK
struct blk_desc *block_dev;
@@ -1141,26 +1185,35 @@ static unsigned long usb_stor_read_write(struct
blk_desc *block_dev,
*/
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("%s: retry #%d, cur_xfer_blks %hu, smallblks %hu\n",
+ __func__, 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_write_10(srb, ss, start, smallblks, is_write)) {
debug("%s ERROR\n", __func__);
usb_request_sense(srb, ss);
- if (retry--)
+ if (retry--) {
+ if (!dec_cur_xfer_blks(udev))
+ smallblks = udev->cur_xfer_blks;
+ retry_flag = true;
goto retry_it;
+ }
blkcnt -= blks;
break;
}
start += smallblks;
blks -= smallblks;
buf_addr += srb->datalen;
+
+ if (!retry_flag && !inc_cur_xfer_blks(udev, blks))
+ smallblks = udev->cur_xfer_blks;
} while (blks != 0);
ss->flags &= ~USB_READY;
@@ -1169,7 +1222,7 @@ retry_it:
__func__, 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;
}
@@ -1256,6 +1309,9 @@ 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..b815816 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;
--
2.6.2.198.g614a2ac
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot
