crypto: omap-aes - Add code to use dmaengine API

Add code to use the new dmaengine API alongside
the existing DMA code that uses the private
OMAP DMA API.  The API to use is chosen by
defining or undefining 'OMAP_AES_DMA_PRIVATE'.

CC: Russell King <rmk+kernel@arm.linux.org.uk>
CC: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/omap-aes.c

@@ -12,6 +12,8 @@
  *
  */
 
+#define OMAP_AES_DMA_PRIVATE
+
 #define pr_fmt(fmt) "%s: " fmt, __func__
 
 #include <linux/err.h>
@@ -22,6 +24,8 @@
 #include <linux/platform_device.h>
 #include <linux/scatterlist.h>
 #include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/omap-dma.h>
 #include <linux/pm_runtime.h>
 #include <linux/io.h>
 #include <linux/crypto.h>
@@ -29,7 +33,8 @@
 #include <crypto/scatterwalk.h>
 #include <crypto/aes.h>
 
-#include <linux/omap-dma.h>
+#define DST_MAXBURST			4
+#define DMA_MIN				(DST_MAXBURST * sizeof(u32))
 
 /* OMAP TRM gives bitfields as start:end, where start is the higher bit
    number. For example 7:0 */
@@ -110,19 +115,33 @@ struct omap_aes_dev {
 	struct ablkcipher_request	*req;
 	size_t				total;
 	struct scatterlist		*in_sg;
+#ifndef OMAP_AES_DMA_PRIVATE
+	struct scatterlist		in_sgl;
+#endif
 	size_t				in_offset;
 	struct scatterlist		*out_sg;
+#ifndef OMAP_AES_DMA_PRIVATE
+	struct scatterlist		out_sgl;
+#endif
 	size_t				out_offset;
 
 	size_t			buflen;
 	void			*buf_in;
 	size_t			dma_size;
 	int			dma_in;
+#ifdef OMAP_AES_DMA_PRIVATE
 	int			dma_lch_in;
+#else
+	struct dma_chan		*dma_lch_in;
+#endif
 	dma_addr_t		dma_addr_in;
 	void			*buf_out;
 	int			dma_out;
+#ifdef OMAP_AES_DMA_PRIVATE
 	int			dma_lch_out;
+#else
+	struct dma_chan		*dma_lch_out;
+#endif
 	dma_addr_t		dma_addr_out;
 };
 
@@ -187,10 +206,17 @@ static int omap_aes_write_ctrl(struct omap_aes_dev *dd)
 		return err;
 
 	val = 0;
+#ifdef OMAP_AES_DMA_PRIVATE
 	if (dd->dma_lch_out >= 0)
 		val |= AES_REG_MASK_DMA_OUT_EN;
 	if (dd->dma_lch_in >= 0)
 		val |= AES_REG_MASK_DMA_IN_EN;
+#else
+	if (dd->dma_lch_out != NULL)
+		val |= AES_REG_MASK_DMA_OUT_EN;
+	if (dd->dma_lch_in != NULL)
+		val |= AES_REG_MASK_DMA_IN_EN;
+#endif
 
 	mask = AES_REG_MASK_DMA_IN_EN | AES_REG_MASK_DMA_OUT_EN;
 
@@ -218,6 +244,7 @@ static int omap_aes_write_ctrl(struct omap_aes_dev *dd)
 
 	omap_aes_write_mask(dd, AES_REG_CTRL, val, mask);
 
+#ifdef OMAP_AES_DMA_PRIVATE
 	/* IN */
 	omap_set_dma_dest_params(dd->dma_lch_in, 0, OMAP_DMA_AMODE_CONSTANT,
 				 dd->phys_base + AES_REG_DATA, 0, 4);
@@ -231,6 +258,7 @@ static int omap_aes_write_ctrl(struct omap_aes_dev *dd)
 
 	omap_set_dma_src_burst_mode(dd->dma_lch_out, OMAP_DMA_DATA_BURST_4);
 	omap_set_dma_dest_burst_mode(dd->dma_lch_out, OMAP_DMA_DATA_BURST_4);
+#endif
 
 	return 0;
 }
@@ -256,6 +284,7 @@ static struct omap_aes_dev *omap_aes_find_dev(struct omap_aes_ctx *ctx)
 	return dd;
 }
 
+#ifdef OMAP_AES_DMA_PRIVATE
 static void omap_aes_dma_callback(int lch, u16 ch_status, void *data)
 {
 	struct omap_aes_dev *dd = data;
@@ -271,13 +300,30 @@ static void omap_aes_dma_callback(int lch, u16 ch_status, void *data)
 	/* dma_lch_out - completed */
 	tasklet_schedule(&dd->done_task);
 }
+#else
+static void omap_aes_dma_out_callback(void *data)
+{
+	struct omap_aes_dev *dd = data;
+
+	/* dma_lch_out - completed */
+	tasklet_schedule(&dd->done_task);
+}
+#endif
 
 static int omap_aes_dma_init(struct omap_aes_dev *dd)
 {
 	int err = -ENOMEM;
+#ifndef OMAP_AES_DMA_PRIVATE
+	dma_cap_mask_t mask;
+#endif
 
+#ifdef OMAP_AES_DMA_PRIVATE
 	dd->dma_lch_out = -1;
 	dd->dma_lch_in = -1;
+#else
+	dd->dma_lch_out = NULL;
+	dd->dma_lch_in = NULL;
+#endif
 
 	dd->buf_in = (void *)__get_free_pages(GFP_KERNEL, OMAP_AES_CACHE_SIZE);
 	dd->buf_out = (void *)__get_free_pages(GFP_KERNEL, OMAP_AES_CACHE_SIZE);
@@ -306,6 +352,7 @@ static int omap_aes_dma_init(struct omap_aes_dev *dd)
 		goto err_map_out;
 	}
 
+#ifdef OMAP_AES_DMA_PRIVATE
 	err = omap_request_dma(dd->dma_in, "omap-aes-rx",
 			       omap_aes_dma_callback, dd, &dd->dma_lch_in);
 	if (err) {
@@ -318,11 +365,33 @@ static int omap_aes_dma_init(struct omap_aes_dev *dd)
 		dev_err(dd->dev, "Unable to request DMA channel\n");
 		goto err_dma_out;
 	}
+#else
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+
+	dd->dma_lch_in = dma_request_channel(mask, omap_dma_filter_fn,
+					     &dd->dma_in);
+	if (!dd->dma_lch_in) {
+		dev_err(dd->dev, "Unable to request in DMA channel\n");
+		goto err_dma_in;
+	}
+
+	dd->dma_lch_out = dma_request_channel(mask, omap_dma_filter_fn,
+					     &dd->dma_out);
+	if (!dd->dma_lch_out) {
+		dev_err(dd->dev, "Unable to request out DMA channel\n");
+		goto err_dma_out;
+	}
+#endif
 
 	return 0;
 
 err_dma_out:
+#ifdef OMAP_AES_DMA_PRIVATE
 	omap_free_dma(dd->dma_lch_in);
+#else
+	dma_release_channel(dd->dma_lch_in);
+#endif
 err_dma_in:
 	dma_unmap_single(dd->dev, dd->dma_addr_out, dd->buflen,
 			 DMA_FROM_DEVICE);
@@ -339,8 +408,13 @@ static int omap_aes_dma_init(struct omap_aes_dev *dd)
 
 static void omap_aes_dma_cleanup(struct omap_aes_dev *dd)
 {
+#ifdef OMAP_AES_DMA_PRIVATE
 	omap_free_dma(dd->dma_lch_out);
 	omap_free_dma(dd->dma_lch_in);
+#else
+	dma_release_channel(dd->dma_lch_out);
+	dma_release_channel(dd->dma_lch_in);
+#endif
 	dma_unmap_single(dd->dev, dd->dma_addr_out, dd->buflen,
 			 DMA_FROM_DEVICE);
 	dma_unmap_single(dd->dev, dd->dma_addr_in, dd->buflen, DMA_TO_DEVICE);
@@ -398,12 +472,24 @@ static int sg_copy(struct scatterlist **sg, size_t *offset, void *buf,
 	return off;
 }
 
+#ifdef OMAP_AES_DMA_PRIVATE
 static int omap_aes_crypt_dma(struct crypto_tfm *tfm, dma_addr_t dma_addr_in,
 			       dma_addr_t dma_addr_out, int length)
+#else
+static int omap_aes_crypt_dma(struct crypto_tfm *tfm,
+		struct scatterlist *in_sg, struct scatterlist *out_sg)
+#endif
 {
 	struct omap_aes_ctx *ctx = crypto_tfm_ctx(tfm);
 	struct omap_aes_dev *dd = ctx->dd;
+#ifdef OMAP_AES_DMA_PRIVATE
 	int len32;
+#else
+	struct dma_async_tx_descriptor *tx_in, *tx_out;
+	struct dma_slave_config cfg;
+	dma_addr_t dma_addr_in = sg_dma_address(in_sg);
+	int ret, length = sg_dma_len(in_sg);
+#endif
 
 	pr_debug("len: %d\n", length);
 
@@ -413,6 +499,7 @@ static int omap_aes_crypt_dma(struct crypto_tfm *tfm, dma_addr_t dma_addr_in,
 		dma_sync_single_for_device(dd->dev, dma_addr_in, length,
 					   DMA_TO_DEVICE);
 
+#ifdef OMAP_AES_DMA_PRIVATE
 	len32 = DIV_ROUND_UP(length, sizeof(u32));
 
 	/* IN */
@@ -433,6 +520,60 @@ static int omap_aes_crypt_dma(struct crypto_tfm *tfm, dma_addr_t dma_addr_in,
 
 	omap_start_dma(dd->dma_lch_in);
 	omap_start_dma(dd->dma_lch_out);
+#else
+	memset(&cfg, 0, sizeof(cfg));
+
+	cfg.src_addr = dd->phys_base + AES_REG_DATA;
+	cfg.dst_addr = dd->phys_base + AES_REG_DATA;
+	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	cfg.src_maxburst = DST_MAXBURST;
+	cfg.dst_maxburst = DST_MAXBURST;
+
+	/* IN */
+	ret = dmaengine_slave_config(dd->dma_lch_in, &cfg);
+	if (ret) {
+		dev_err(dd->dev, "can't configure IN dmaengine slave: %d\n",
+			ret);
+		return ret;
+	}
+
+	tx_in = dmaengine_prep_slave_sg(dd->dma_lch_in, in_sg, 1,
+					DMA_MEM_TO_DEV,
+					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!tx_in) {
+		dev_err(dd->dev, "IN prep_slave_sg() failed\n");
+		return -EINVAL;
+	}
+
+	/* No callback necessary */
+	tx_in->callback_param = dd;
+
+	/* OUT */
+	ret = dmaengine_slave_config(dd->dma_lch_out, &cfg);
+	if (ret) {
+		dev_err(dd->dev, "can't configure OUT dmaengine slave: %d\n",
+			ret);
+		return ret;
+	}
+
+	tx_out = dmaengine_prep_slave_sg(dd->dma_lch_out, out_sg, 1,
+					DMA_DEV_TO_MEM,
+					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!tx_out) {
+		dev_err(dd->dev, "OUT prep_slave_sg() failed\n");
+		return -EINVAL;
+	}
+
+	tx_out->callback = omap_aes_dma_out_callback;
+	tx_out->callback_param = dd;
+
+	dmaengine_submit(tx_in);
+	dmaengine_submit(tx_out);
+
+	dma_async_issue_pending(dd->dma_lch_in);
+	dma_async_issue_pending(dd->dma_lch_out);
+#endif
 
 	/* start DMA or disable idle mode */
 	omap_aes_write_mask(dd, AES_REG_MASK, AES_REG_MASK_START,
@@ -448,6 +589,10 @@ static int omap_aes_crypt_dma_start(struct omap_aes_dev *dd)
 	int err, fast = 0, in, out;
 	size_t count;
 	dma_addr_t addr_in, addr_out;
+#ifndef OMAP_AES_DMA_PRIVATE
+	struct scatterlist *in_sg, *out_sg;
+	int len32;
+#endif
 
 	pr_debug("total: %d\n", dd->total);
 
@@ -486,6 +631,11 @@ static int omap_aes_crypt_dma_start(struct omap_aes_dev *dd)
 		addr_in = sg_dma_address(dd->in_sg);
 		addr_out = sg_dma_address(dd->out_sg);
 
+#ifndef OMAP_AES_DMA_PRIVATE
+		in_sg = dd->in_sg;
+		out_sg = dd->out_sg;
+#endif
+
 		dd->flags |= FLAGS_FAST;
 
 	} else {
@@ -493,6 +643,29 @@ static int omap_aes_crypt_dma_start(struct omap_aes_dev *dd)
 		count = sg_copy(&dd->in_sg, &dd->in_offset, dd->buf_in,
 				 dd->buflen, dd->total, 0);
 
+#ifndef OMAP_AES_DMA_PRIVATE
+		len32 = DIV_ROUND_UP(count, DMA_MIN) * DMA_MIN;
+
+		/*
+		 * The data going into the AES module has been copied
+		 * to a local buffer and the data coming out will go
+		 * into a local buffer so set up local SG entries for
+		 * both.
+		 */
+		sg_init_table(&dd->in_sgl, 1);
+		dd->in_sgl.offset = dd->in_offset;
+		sg_dma_len(&dd->in_sgl) = len32;
+		sg_dma_address(&dd->in_sgl) = dd->dma_addr_in;
+
+		sg_init_table(&dd->out_sgl, 1);
+		dd->out_sgl.offset = dd->out_offset;
+		sg_dma_len(&dd->out_sgl) = len32;
+		sg_dma_address(&dd->out_sgl) = dd->dma_addr_out;
+
+		in_sg = &dd->in_sgl;
+		out_sg = &dd->out_sgl;
+#endif
+
 		addr_in = dd->dma_addr_in;
 		addr_out = dd->dma_addr_out;
 
@@ -502,7 +675,11 @@ static int omap_aes_crypt_dma_start(struct omap_aes_dev *dd)
 
 	dd->total -= count;
 
+#ifdef OMAP_AES_DMA_PRIVATE
 	err = omap_aes_crypt_dma(tfm, addr_in, addr_out, count);
+#else
+	err = omap_aes_crypt_dma(tfm, in_sg, out_sg);
+#endif
 	if (err) {
 		dma_unmap_sg(dd->dev, dd->in_sg, 1, DMA_TO_DEVICE);
 		dma_unmap_sg(dd->dev, dd->out_sg, 1, DMA_TO_DEVICE);
@@ -532,8 +709,13 @@ static int omap_aes_crypt_dma_stop(struct omap_aes_dev *dd)
 
 	omap_aes_write_mask(dd, AES_REG_MASK, 0, AES_REG_MASK_START);
 
+#ifdef OMAP_AES_DMA_PRIVATE
 	omap_stop_dma(dd->dma_lch_in);
 	omap_stop_dma(dd->dma_lch_out);
+#else
+	dmaengine_terminate_all(dd->dma_lch_in);
+	dmaengine_terminate_all(dd->dma_lch_out);
+#endif
 
 	if (dd->flags & FLAGS_FAST) {
 		dma_unmap_sg(dd->dev, dd->out_sg, 1, DMA_FROM_DEVICE);