From: linus.walleij@linaro.org (Linus Walleij)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 16/18] dmaengine/amba-pl08x: Add support for sg len greater than one for slave transfers
Date: Thu, 8 Sep 2011 01:01:15 +0200 [thread overview]
Message-ID: <CAKnu2Mp3Ui7jZS2kjJykjuzcTzJhiAkoaVxZ2+tQX0banGh6mw@mail.gmail.com> (raw)
In-Reply-To: <438BB0150E931F4B9CE701519A4463010871804A4C@bgsmsx502.gar.corp.intel.com>
2011/9/7 Koul, Vinod <vinod.koul@intel.com>:
> On Thu, 2011-09-01 at 15:37 +0530, Viresh Kumar wrote:
>> On 8/26/2011 2:21 PM, Viresh Kumar wrote:
>> > I just wanted to know, whether i need to do any other modification in this patch or not?
>>
>> Hello,
>>
>> Do i need to update anything in this patch? Or can this be pushed as it is?
>>
> I thought Linus W, and Russell had some comments on this.
I think the patch brings valuable functionality we don't want to loose when
there is a solution. Basically the dmaengine has a contract to handle
sglists of any lengths and it's a pity that we don't, and I suspect Viresh
cannot use the driver for MMC unless something like this is added, so
Acked-by: Linus Walleij <linus.walleij@linaro.org>
BUT I think it is possible to rewrite it a bit later so as to get a better
handling of this. Isn't Russells initial remark that the LLI:s can simply just
take in the entire sglist at once true?
Check for example in drivers/dma/coh901318.c which evidently has
a LLI format similar or identical to what pl08x use (which is another
reason to refactor this later):
It will just fill in LLIs for all the elements of the sglist, and off you go.
Like this:
/* The dma only supports transmitting packages up to
* MAX_DMA_PACKET_SIZE. Calculate to total number of
* dma elemts required to send the entire sg list
*/
for_each_sg(sgl, sg, sg_len, i) {
unsigned int factor;
size = sg_dma_len(sg);
if (size <= MAX_DMA_PACKET_SIZE) {
len++;
continue;
}
factor = size >> MAX_DMA_PACKET_SIZE_SHIFT;
if ((factor << MAX_DMA_PACKET_SIZE_SHIFT) < size)
factor++;
len += factor;
}
pr_debug("Allocate %d lli:s for this transfer\n", len);
lli = coh901318_lli_alloc(&cohc->base->pool, len);
if (lli == NULL)
goto err_dma_alloc;
/* initiate allocated lli list */
ret = coh901318_lli_fill_sg(&cohc->base->pool, lli, sgl, sg_len,
cohc_dev_addr(cohc),
ctrl_chained,
ctrl,
ctrl_last,
direction, COH901318_CX_CTRL_TC_IRQ_ENABLE);
if (ret)
goto err_lli_fill;
The rest of interesting code is in coh901318_lli_fill_sg() as you can
see.
Evidently this need to be fixed as part of factoring out the LLI handling
from PL08x and coh901318 into a single one. If we ever get to it.
Yours,
Linus Walleij
next prev parent reply other threads:[~2011-09-07 23:01 UTC|newest]
Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-29 10:49 [PATCH 00/18] dmaengine/amba-pl08x updates Viresh Kumar
2011-07-29 10:49 ` [PATCH 01/18] ARM: asm/pl080.h: Protect against multiple inclusion of header file Viresh Kumar
2011-07-30 22:16 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 02/18] dmaengine/amba-pl08x: Resolve formatting issues Viresh Kumar
2011-07-29 11:00 ` Russell King - ARM Linux
2011-07-29 11:21 ` viresh kumar
2011-07-29 12:05 ` Koul, Vinod
2011-07-29 15:25 ` viresh kumar
2011-07-29 10:49 ` [PATCH 03/18] dmaengine/amba-pl08x: Complete doc comment for struct pl08x_txd Viresh Kumar
2011-07-29 10:49 ` [PATCH 04/18] dmaengine/amba-pl08x: Remove redundant comment and rewrite original Viresh Kumar
2011-07-29 12:09 ` Koul, Vinod
2011-07-29 15:47 ` viresh kumar
2011-07-29 16:34 ` Russell King - ARM Linux
2011-07-30 22:32 ` Linus Walleij
2011-07-30 22:57 ` Russell King - ARM Linux
2011-07-30 23:37 ` Linus Walleij
2011-07-31 5:51 ` viresh kumar
2011-07-31 9:06 ` Russell King - ARM Linux
2011-07-29 10:49 ` [PATCH 05/18] dmaengine/amba-pl08x: Changing few prints to dev_dbg from dev_info Viresh Kumar
2011-07-30 22:34 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 06/18] dmaengine/amba-pl08x: Simplify pl08x_ensure_on() Viresh Kumar
2011-07-30 22:36 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 07/18] dmaengine/amba-pl08x: Enable/Disable amba_pclk with channel requests Viresh Kumar
2011-07-30 12:07 ` Russell King - ARM Linux
2011-07-30 13:05 ` Russell King - ARM Linux
2011-07-30 23:53 ` Linus Walleij
2011-07-31 0:04 ` Linus Walleij
2011-07-31 17:04 ` Russell King - ARM Linux
2011-08-02 9:05 ` Linus Walleij
2011-08-03 12:55 ` Russell King - ARM Linux
2011-08-09 19:50 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 08/18] dmaengine/amba-pl08x: No need to check "ch->signal < 0" Viresh Kumar
2011-07-31 0:09 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 09/18] dmaengine/amba-pl08x: Schedule tasklet in case of error interrupt Viresh Kumar
2011-07-29 12:16 ` Koul, Vinod
2011-07-29 13:02 ` Russell King - ARM Linux
2011-07-29 15:30 ` viresh kumar
2011-08-04 4:25 ` Koul, Vinod
2011-08-04 5:54 ` viresh kumar
2011-08-04 5:32 ` Koul, Vinod
2011-08-14 8:29 ` Russell King - ARM Linux
2011-07-31 0:19 ` Linus Walleij
2011-07-31 5:33 ` viresh kumar
2011-07-29 10:49 ` [PATCH 10/18] dmaengine/amba-pl08x: Get rid of pl08x_pre_boundary() Viresh Kumar
2011-07-29 11:05 ` Russell King - ARM Linux
2011-07-29 12:32 ` Koul, Vinod
2011-07-29 15:58 ` viresh kumar
2011-07-29 12:19 ` Koul, Vinod
2011-07-29 15:40 ` viresh kumar
2011-07-31 0:24 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 11/18] dmaengine/amba-pl08x: max_bytes_per_lli is TRANSFER_SIZE * src_width (not MIN(width)) Viresh Kumar
2011-07-31 0:27 ` Linus Walleij
2011-07-31 9:09 ` Russell King - ARM Linux
2011-07-29 10:49 ` [PATCH 12/18] dmaengine/amba-pl08x: Add prep_single_byte_llis() routine Viresh Kumar
2011-07-29 11:06 ` Russell King - ARM Linux
2011-07-29 11:30 ` viresh kumar
2011-07-29 10:49 ` [PATCH 13/18] dmaengine/amba-pl08x: Align lli_len to max(src.width, dst.width) Viresh Kumar
2011-07-29 12:43 ` Koul, Vinod
2011-07-29 15:39 ` viresh kumar
2011-07-31 0:30 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 14/18] dmaengine/amba-pl08x: Choose peripheral bus as master bus Viresh Kumar
2011-07-31 0:36 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 15/18] dmaengine/amba-pl08x: Pass flow controller information with slave channel data Viresh Kumar
2011-07-29 11:10 ` Russell King - ARM Linux
2011-07-29 11:31 ` viresh kumar
2011-07-31 0:40 ` Linus Walleij
2011-07-31 5:36 ` viresh kumar
2011-07-29 10:49 ` [PATCH 16/18] dmaengine/amba-pl08x: Add support for sg len greater than one for slave transfers Viresh Kumar
2011-07-31 0:41 ` Linus Walleij
2011-08-14 8:36 ` Russell King - ARM Linux
2011-08-15 10:11 ` Linus Walleij
2011-08-18 8:38 ` Viresh Kumar
2011-08-21 8:33 ` Russell King - ARM Linux
2011-08-23 4:22 ` Viresh Kumar
2011-08-23 5:20 ` Koul, Vinod
2011-08-26 3:41 ` Viresh Kumar
2011-08-26 8:03 ` Linus Walleij
2011-08-26 8:51 ` Viresh Kumar
2011-09-01 10:07 ` Viresh Kumar
2011-09-07 18:42 ` Koul, Vinod
2011-09-07 23:01 ` Linus Walleij [this message]
2011-09-08 3:50 ` Viresh Kumar
2011-09-08 10:29 ` Linus Walleij
2011-09-08 21:54 ` [PATCH 16/18] dmaengine/ambhe rest oa-pl08x: " Vinod Koul
2011-09-20 6:19 ` Vinod Koul
2011-09-20 6:27 ` Viresh Kumar
2011-09-20 8:08 ` Vinod Koul
2011-07-29 10:49 ` [PATCH 17/18] dmaengine/amba-pl08x: Check txd->llis_va before freeing dma_pool Viresh Kumar
2011-07-31 0:44 ` Linus Walleij
2011-07-29 10:49 ` [PATCH 18/18] dmaengine/amba-pl08x: Call pl08x_free_txd() instead of calling kfree() directly Viresh Kumar
2011-07-29 11:15 ` Russell King - ARM Linux
2011-07-29 11:38 ` viresh kumar
2011-07-31 0:45 ` Linus Walleij
2011-07-31 5:39 ` viresh kumar
2011-07-29 10:57 ` [PATCH 00/18] dmaengine/amba-pl08x updates Russell King - ARM Linux
2011-07-29 11:14 ` viresh kumar
2011-07-29 11:19 ` Russell King - ARM Linux
2011-07-29 11:23 ` viresh kumar
2011-07-29 12:43 ` Russell King - ARM Linux
2011-07-29 15:22 ` viresh kumar
2011-07-29 11:58 ` Koul, Vinod
2011-08-01 5:30 ` viresh kumar
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