From patchwork Wed Aug 14 23:12:47 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 2844866 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 8E248BF546 for ; Wed, 14 Aug 2013 23:14:17 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 93AE9205D8 for ; Wed, 14 Aug 2013 23:14:16 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5802320621 for ; Wed, 14 Aug 2013 23:14:15 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V9kGM-0005Jk-7i; Wed, 14 Aug 2013 23:13:58 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1V9kGH-0001GK-SO; Wed, 14 Aug 2013 23:13:53 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V9kG1-0001C7-EG for linux-arm-kernel@lists.infradead.org; Wed, 14 Aug 2013 23:13:38 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id r7ENDCmH031214; Wed, 14 Aug 2013 18:13:12 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r7ENDCDx026622; Wed, 14 Aug 2013 18:13:12 -0500 Received: from dlelxv22.itg.ti.com (172.17.1.197) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.2.342.3; Wed, 14 Aug 2013 18:13:12 -0500 Received: from joel-laptop.itg.ti.com (h56-176.vpn.ti.com [172.24.56.176]) by dlelxv22.itg.ti.com (8.13.8/8.13.8) with ESMTP id r7ENCnGt031508; Wed, 14 Aug 2013 18:13:11 -0500 From: Joel Fernandes To: Herbert Xu , "David S. Miller" , Mark Greer , Tony Lindgren , Santosh Shilimkar , Rajendra Nayak , Lokesh Vutla Subject: [PATCH 08/10] crypto: omap-aes: PIO mode: Add IRQ handler and walk SGs Date: Wed, 14 Aug 2013 18:12:47 -0500 Message-ID: <1376521969-16807-9-git-send-email-joelf@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1376521969-16807-1-git-send-email-joelf@ti.com> References: <1376521969-16807-1-git-send-email-joelf@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130814_191337_641512_4D663176 X-CRM114-Status: GOOD ( 18.18 ) X-Spam-Score: -9.7 (---------) Cc: Joel Fernandes , Linux OMAP List , Linux Kernel Mailing List , Linux ARM Kernel List , Linux Crypto Mailing List X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-7.0 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP We add an IRQ handler that implements a state-machine for PIO-mode and data structures for walking the scatter-gather list. The IRQ handler is called in succession both when data is available to read or next data can be sent for processing. This process continues till the entire in/out SG lists have been walked. Once the SG-list has been completely walked, the IRQ handler schedules the done_task tasklet. Also add a useful macro that is used through out the IRQ code for a common pattern of calculating how much an SG list has been walked. This improves code readability and avoids checkpatch errors. Signed-off-by: Joel Fernandes --- drivers/crypto/omap-aes.c | 90 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) diff --git a/drivers/crypto/omap-aes.c b/drivers/crypto/omap-aes.c index c057eac..891455b 100644 --- a/drivers/crypto/omap-aes.c +++ b/drivers/crypto/omap-aes.c @@ -46,6 +46,8 @@ #define DST_MAXBURST 4 #define DMA_MIN (DST_MAXBURST * sizeof(u32)) +#define _calc_walked(inout) (dd->inout##_walk.offset - dd->inout##_sg->offset) + /* OMAP TRM gives bitfields as start:end, where start is the higher bit number. For example 7:0 */ #define FLD_MASK(start, end) (((1 << ((start) - (end) + 1)) - 1) << (end)) @@ -98,6 +100,8 @@ #define FLAGS_FAST BIT(5) #define FLAGS_BUSY BIT(6) +#define AES_BLOCK_WORDS (AES_BLOCK_SIZE >> 2) + struct omap_aes_ctx { struct omap_aes_dev *dd; @@ -163,6 +167,8 @@ struct omap_aes_dev { size_t total; struct scatterlist *in_sg; struct scatterlist *out_sg; + struct scatter_walk in_walk; + struct scatter_walk out_walk; int dma_in; struct dma_chan *dma_lch_in; int dma_out; @@ -862,6 +868,90 @@ static const struct omap_aes_pdata omap_aes_pdata_omap4 = { .minor_shift = 0, }; +static irqreturn_t omap_aes_irq(int irq, void *dev_id) +{ + struct omap_aes_dev *dd = dev_id; + u32 status, i; + u32 *src, *dst; + + status = omap_aes_read(dd, AES_REG_IRQ_STATUS(dd)); + if (status & AES_REG_IRQ_DATA_IN) { + omap_aes_write(dd, AES_REG_IRQ_ENABLE(dd), 0x0); + + BUG_ON(!dd->in_sg); + + BUG_ON(_calc_walked(in) > dd->in_sg->length); + + src = sg_virt(dd->in_sg) + _calc_walked(in); + + for (i = 0; i < AES_BLOCK_WORDS; i++) { + omap_aes_write(dd, AES_REG_DATA_N(dd, i), *src); + + scatterwalk_advance(&dd->in_walk, 4); + if (dd->in_sg->length == _calc_walked(in)) { + dd->in_sg = scatterwalk_sg_next(dd->in_sg); + if (dd->in_sg) { + scatterwalk_start(&dd->in_walk, + dd->in_sg); + src = sg_virt(dd->in_sg) + + _calc_walked(in); + } + } else { + src++; + } + } + + /* Clear IRQ status */ + status &= ~AES_REG_IRQ_DATA_IN; + omap_aes_write(dd, AES_REG_IRQ_STATUS(dd), status); + + /* Enable DATA_OUT interrupt */ + omap_aes_write(dd, AES_REG_IRQ_ENABLE(dd), 0x4); + + } else if (status & AES_REG_IRQ_DATA_OUT) { + omap_aes_write(dd, AES_REG_IRQ_ENABLE(dd), 0x0); + + BUG_ON(!dd->out_sg); + + BUG_ON(_calc_walked(out) > dd->out_sg->length); + + dst = sg_virt(dd->out_sg) + _calc_walked(out); + + for (i = 0; i < AES_BLOCK_WORDS; i++) { + *dst = omap_aes_read(dd, AES_REG_DATA_N(dd, i)); + scatterwalk_advance(&dd->out_walk, 4); + if (dd->out_sg->length == _calc_walked(out)) { + dd->out_sg = scatterwalk_sg_next(dd->out_sg); + if (dd->out_sg) { + scatterwalk_start(&dd->out_walk, + dd->out_sg); + dst = sg_virt(dd->out_sg) + + _calc_walked(out); + } + } else { + dst++; + } + } + + dd->total -= AES_BLOCK_SIZE; + + BUG_ON(dd->total < 0); + + /* Clear IRQ status */ + status &= ~AES_REG_IRQ_DATA_OUT; + omap_aes_write(dd, AES_REG_IRQ_STATUS(dd), status); + + if (!dd->total) + /* All bytes read! */ + tasklet_schedule(&dd->done_task); + else + /* Enable DATA_IN interrupt for next block */ + omap_aes_write(dd, AES_REG_IRQ_ENABLE(dd), 0x2); + } + + return IRQ_HANDLED; +} + static const struct of_device_id omap_aes_of_match[] = { { .compatible = "ti,omap2-aes",