Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1af8ea86 authored by Bharat Bhushan's avatar Bharat Bhushan Committed by Herbert Xu
Browse files

crypto: caam - Using alloc_coherent for caam job rings 



The caam job rings (input/output job ring) are allocated using
dma_map_single(). These job rings can be visualized as the ring
buffers in which the jobs are en-queued/de-queued. The s/w enqueues
the jobs in input job ring which h/w dequeues and after processing
it copies the jobs in output job ring. Software then de-queues the
job from output ring. Using dma_map/unmap_single() is not preferred
way to allocate memory for this type of requirements because this
adds un-necessary complexity.

Example, if bounce buffer (SWIOTLB) will get used then to make any
change visible in this memory to other processing unit requires
dmap_unmap_single() or dma_sync_single_for_cpu/device(). The
dma_unmap_single() can not be used as this will free the bounce
buffer, this will require changing the job rings on running system
and I seriously doubt that it will be not possible or very complex
to implement. Also using dma_sync_single_for_cpu/device() will also
add unnecessary complexity.

The simple and preferred way is using dma_alloc_coherent() for these
type of memory requirements.

This resolves the Linux boot crash issue when "swiotlb=force" is set
in bootargs on systems which have memory more than 4G.

Signed-off-by: default avatarBharat Bhushan <bharat.bhushan@freescale.com>
Acked-by: default avatarKim Phillips <kim.phillips@freescale.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 26c8aaeb

drivers/crypto/caam/jr.c

+9 −36
Original line number Original line Diff line number Diff line
@@ -339,10 +339,11 @@ static int caam_jr_init(struct device *dev) 
	if (error)

	if (error)

		return error;

		return error;





	jrp->inpring = kzalloc(sizeof(dma_addr_t) * JOBR_DEPTH,

	jrp->inpring = dma_alloc_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,

			       GFP_KERNEL | GFP_DMA);

					  &inpbusaddr, GFP_KERNEL);

	jrp->outring = kzalloc(sizeof(struct jr_outentry) *



			       JOBR_DEPTH, GFP_KERNEL | GFP_DMA);

	jrp->outring = dma_alloc_coherent(dev, sizeof(struct jr_outentry) *

					  JOBR_DEPTH, &outbusaddr, GFP_KERNEL);





	jrp->entinfo = kzalloc(sizeof(struct caam_jrentry_info) * JOBR_DEPTH,

	jrp->entinfo = kzalloc(sizeof(struct caam_jrentry_info) * JOBR_DEPTH,

			       GFP_KERNEL);

			       GFP_KERNEL);
@@ -358,31 +359,6 @@ static int caam_jr_init(struct device *dev) 
		jrp->entinfo[i].desc_addr_dma = !0;

		jrp->entinfo[i].desc_addr_dma = !0;





	/* Setup rings */

	/* Setup rings */

	inpbusaddr = dma_map_single(dev, jrp->inpring,

				    sizeof(dma_addr_t) * JOBR_DEPTH,

				    DMA_BIDIRECTIONAL);

	if (dma_mapping_error(dev, inpbusaddr)) {

		dev_err(dev, "caam_jr_init(): can't map input ring\n");

		kfree(jrp->inpring);

		kfree(jrp->outring);

		kfree(jrp->entinfo);

		return -EIO;

	}



	outbusaddr = dma_map_single(dev, jrp->outring,

				    sizeof(struct jr_outentry) * JOBR_DEPTH,

				    DMA_BIDIRECTIONAL);

	if (dma_mapping_error(dev, outbusaddr)) {

		dev_err(dev, "caam_jr_init(): can't map output ring\n");

		dma_unmap_single(dev, inpbusaddr,

				 sizeof(dma_addr_t) * JOBR_DEPTH,

				 DMA_BIDIRECTIONAL);

		kfree(jrp->inpring);

		kfree(jrp->outring);

		kfree(jrp->entinfo);

		return -EIO;

	}



	jrp->inp_ring_write_index = 0;

	jrp->inp_ring_write_index = 0;

	jrp->out_ring_read_index = 0;

	jrp->out_ring_read_index = 0;

	jrp->head = 0;

	jrp->head = 0;
@@ -426,13 +402,10 @@ int caam_jr_shutdown(struct device *dev) 
	/* Free rings */

	/* Free rings */

	inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);

	inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);

	outbusaddr = rd_reg64(&jrp->rregs->outring_base);

	outbusaddr = rd_reg64(&jrp->rregs->outring_base);

	dma_unmap_single(dev, outbusaddr,

	dma_free_coherent(dev, sizeof(dma_addr_t) * JOBR_DEPTH,

			 sizeof(struct jr_outentry) * JOBR_DEPTH,

			  jrp->inpring, inpbusaddr);

			 DMA_BIDIRECTIONAL);

	dma_free_coherent(dev, sizeof(struct jr_outentry) * JOBR_DEPTH,

	dma_unmap_single(dev, inpbusaddr, sizeof(dma_addr_t) * JOBR_DEPTH,

			  jrp->outring, outbusaddr);

			 DMA_BIDIRECTIONAL);

	kfree(jrp->outring);

	kfree(jrp->inpring);

	kfree(jrp->entinfo);

	kfree(jrp->entinfo);





	return ret;

	return ret;