From mboxrd@z Thu Jan 1 00:00:00 1970 From: akpm@linux-foundation.org Subject: - synclink_gt-add-rx-dma-buffer-fill-level-control.patch removed from -mm tree Date: Mon, 21 Jul 2008 14:34:25 -0700 Message-ID: <200807212134.m6LLYPRY025666@imap1.linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:42301 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751027AbYGUVgd (ORCPT ); Mon, 21 Jul 2008 17:36:33 -0400 Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: paulkf@microgate.com, alan@lxorguk.ukuu.org.uk, mm-commits@vger.kernel.org The patch titled synclink_gt: add rx DMA buffer fill level control has been removed from the -mm tree. Its filename was synclink_gt-add-rx-dma-buffer-fill-level-control.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: synclink_gt: add rx DMA buffer fill level control From: Paul Fulghum Add run time control for receive DMA buffer fill level to allow application to control receive latency when using stream oriented serial protocols that pass receive data to application only after a DMA buffer fills. This was previously a compile time option, but run time control is needed when application changes data rate (and latency requirements) or uses different data rates on different ports. Signed-off-by: Paul Fulghum Cc: Alan Cox Signed-off-by: Andrew Morton --- drivers/char/synclink_gt.c | 42 ++++++++++++++++++++++------------- 1 file changed, 27 insertions(+), 15 deletions(-) diff -puN drivers/char/synclink_gt.c~synclink_gt-add-rx-dma-buffer-fill-level-control drivers/char/synclink_gt.c --- a/drivers/char/synclink_gt.c~synclink_gt-add-rx-dma-buffer-fill-level-control +++ a/drivers/char/synclink_gt.c @@ -299,7 +299,7 @@ struct slgt_info { u32 idle_mode; u32 max_frame_size; /* as set by device config */ - unsigned int raw_rx_size; + unsigned int rbuf_fill_level; unsigned int if_mode; /* device status */ @@ -2676,8 +2676,29 @@ static int tx_abort(struct slgt_info *in static int rx_enable(struct slgt_info *info, int enable) { unsigned long flags; - DBGINFO(("%s rx_enable(%d)\n", info->device_name, enable)); + unsigned int rbuf_fill_level; + DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable)); spin_lock_irqsave(&info->lock,flags); + /* + * enable[31..16] = receive DMA buffer fill level + * 0 = noop (leave fill level unchanged) + * fill level must be multiple of 4 and <= buffer size + */ + rbuf_fill_level = ((unsigned int)enable) >> 16; + if (rbuf_fill_level) { + if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) + return -EINVAL; + info->rbuf_fill_level = rbuf_fill_level; + rx_stop(info); /* restart receiver to use new fill level */ + } + + /* + * enable[1..0] = receiver enable command + * 0 = disable + * 1 = enable + * 2 = enable or force hunt mode if already enabled + */ + enable &= 3; if (enable) { if (!info->rx_enabled) rx_start(info); @@ -3443,7 +3464,7 @@ static struct slgt_info *alloc_dev(int a info->magic = MGSL_MAGIC; INIT_WORK(&info->task, bh_handler); info->max_frame_size = 4096; - info->raw_rx_size = DMABUFSIZE; + info->rbuf_fill_level = DMABUFSIZE; info->port.close_delay = 5*HZ/10; info->port.closing_wait = 30*HZ; init_waitqueue_head(&info->status_event_wait_q); @@ -4454,16 +4475,7 @@ static void free_rbufs(struct slgt_info while(!done) { /* reset current buffer for reuse */ info->rbufs[i].status = 0; - switch(info->params.mode) { - case MGSL_MODE_RAW: - case MGSL_MODE_MONOSYNC: - case MGSL_MODE_BISYNC: - set_desc_count(info->rbufs[i], info->raw_rx_size); - break; - default: - set_desc_count(info->rbufs[i], DMABUFSIZE); - } - + set_desc_count(info->rbufs[i], info->rbuf_fill_level); if (i == last) done = 1; if (++i == info->rbuf_count) @@ -4570,7 +4582,7 @@ check_again: DBGBH(("%s rx frame status=%04X size=%d\n", info->device_name, status, framesize)); - DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, DMABUFSIZE), "rx"); + DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx"); if (framesize) { if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) { @@ -4590,7 +4602,7 @@ check_again: info->icount.rxok++; while(copy_count) { - int partial_count = min(copy_count, DMABUFSIZE); + int partial_count = min_t(int, copy_count, info->rbuf_fill_level); memcpy(p, info->rbufs[i].buf, partial_count); p += partial_count; copy_count -= partial_count; _ Patches currently in -mm which might be from paulkf@microgate.com are linux-next.patch