linux/drivers/crypto/marvell/tdma.c
Boris BREZILLON db509a4533 crypto: marvell/cesa - add TDMA support
The CESA IP supports CPU offload through a dedicated DMA engine (TDMA)
which can control the crypto block.
When you use this mode, all the required data (operation metadata and
payload data) are transferred using DMA, and the results are retrieved
through DMA when possible (hash results are not retrieved through DMA yet),
thus reducing the involvement of the CPU and providing better performances
in most cases (for small requests, the cost of DMA preparation might
exceed the performance gain).

Note that some CESA IPs do not embed this dedicated DMA, hence the
activation of this feature on a per platform basis.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-19 22:18:03 +08:00

224 lines
5.5 KiB
C

/*
* Provide TDMA helper functions used by cipher and hash algorithm
* implementations.
*
* Author: Boris Brezillon <boris.brezillon@free-electrons.com>
* Author: Arnaud Ebalard <arno@natisbad.org>
*
* This work is based on an initial version written by
* Sebastian Andrzej Siewior < sebastian at breakpoint dot cc >
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#include "cesa.h"
bool mv_cesa_req_dma_iter_next_transfer(struct mv_cesa_dma_iter *iter,
struct mv_cesa_sg_dma_iter *sgiter,
unsigned int len)
{
if (!sgiter->sg)
return false;
sgiter->op_offset += len;
sgiter->offset += len;
if (sgiter->offset == sg_dma_len(sgiter->sg)) {
if (sg_is_last(sgiter->sg))
return false;
sgiter->offset = 0;
sgiter->sg = sg_next(sgiter->sg);
}
if (sgiter->op_offset == iter->op_len)
return false;
return true;
}
void mv_cesa_dma_step(struct mv_cesa_tdma_req *dreq)
{
struct mv_cesa_engine *engine = dreq->base.engine;
writel(0, engine->regs + CESA_SA_CFG);
mv_cesa_set_int_mask(engine, CESA_SA_INT_ACC0_IDMA_DONE);
writel(CESA_TDMA_DST_BURST_128B | CESA_TDMA_SRC_BURST_128B |
CESA_TDMA_NO_BYTE_SWAP | CESA_TDMA_EN,
engine->regs + CESA_TDMA_CONTROL);
writel(CESA_SA_CFG_ACT_CH0_IDMA | CESA_SA_CFG_MULTI_PKT |
CESA_SA_CFG_CH0_W_IDMA | CESA_SA_CFG_PARA_DIS,
engine->regs + CESA_SA_CFG);
writel(dreq->chain.first->cur_dma,
engine->regs + CESA_TDMA_NEXT_ADDR);
writel(CESA_SA_CMD_EN_CESA_SA_ACCL0, engine->regs + CESA_SA_CMD);
}
void mv_cesa_dma_cleanup(struct mv_cesa_tdma_req *dreq)
{
struct mv_cesa_tdma_desc *tdma;
for (tdma = dreq->chain.first; tdma;) {
struct mv_cesa_tdma_desc *old_tdma = tdma;
if (tdma->flags & CESA_TDMA_OP)
dma_pool_free(cesa_dev->dma->op_pool, tdma->op,
le32_to_cpu(tdma->src));
tdma = tdma->next;
dma_pool_free(cesa_dev->dma->tdma_desc_pool, old_tdma,
le32_to_cpu(old_tdma->cur_dma));
}
dreq->chain.first = NULL;
dreq->chain.last = NULL;
}
void mv_cesa_dma_prepare(struct mv_cesa_tdma_req *dreq,
struct mv_cesa_engine *engine)
{
struct mv_cesa_tdma_desc *tdma;
for (tdma = dreq->chain.first; tdma; tdma = tdma->next) {
if (tdma->flags & CESA_TDMA_DST_IN_SRAM)
tdma->dst = cpu_to_le32(tdma->dst + engine->sram_dma);
if (tdma->flags & CESA_TDMA_SRC_IN_SRAM)
tdma->src = cpu_to_le32(tdma->src + engine->sram_dma);
if (tdma->flags & CESA_TDMA_OP)
mv_cesa_adjust_op(engine, tdma->op);
}
}
static struct mv_cesa_tdma_desc *
mv_cesa_dma_add_desc(struct mv_cesa_tdma_chain *chain, gfp_t flags)
{
struct mv_cesa_tdma_desc *new_tdma = NULL;
dma_addr_t dma_handle;
new_tdma = dma_pool_alloc(cesa_dev->dma->tdma_desc_pool, flags,
&dma_handle);
if (!new_tdma)
return ERR_PTR(-ENOMEM);
memset(new_tdma, 0, sizeof(*new_tdma));
new_tdma->cur_dma = cpu_to_le32(dma_handle);
if (chain->last) {
chain->last->next_dma = new_tdma->cur_dma;
chain->last->next = new_tdma;
} else {
chain->first = new_tdma;
}
chain->last = new_tdma;
return new_tdma;
}
struct mv_cesa_op_ctx *mv_cesa_dma_add_op(struct mv_cesa_tdma_chain *chain,
const struct mv_cesa_op_ctx *op_templ,
bool skip_ctx,
gfp_t flags)
{
struct mv_cesa_tdma_desc *tdma;
struct mv_cesa_op_ctx *op;
dma_addr_t dma_handle;
tdma = mv_cesa_dma_add_desc(chain, flags);
if (IS_ERR(tdma))
return ERR_CAST(tdma);
op = dma_pool_alloc(cesa_dev->dma->op_pool, flags, &dma_handle);
if (!op)
return ERR_PTR(-ENOMEM);
*op = *op_templ;
tdma = chain->last;
tdma->op = op;
tdma->byte_cnt = (skip_ctx ? sizeof(op->desc) : sizeof(*op)) | BIT(31);
tdma->src = dma_handle;
tdma->flags = CESA_TDMA_DST_IN_SRAM | CESA_TDMA_OP;
return op;
}
int mv_cesa_dma_add_data_transfer(struct mv_cesa_tdma_chain *chain,
dma_addr_t dst, dma_addr_t src, u32 size,
u32 flags, gfp_t gfp_flags)
{
struct mv_cesa_tdma_desc *tdma;
tdma = mv_cesa_dma_add_desc(chain, gfp_flags);
if (IS_ERR(tdma))
return PTR_ERR(tdma);
tdma->byte_cnt = size | BIT(31);
tdma->src = src;
tdma->dst = dst;
flags &= (CESA_TDMA_DST_IN_SRAM | CESA_TDMA_SRC_IN_SRAM);
tdma->flags = flags | CESA_TDMA_DATA;
return 0;
}
int mv_cesa_dma_add_dummy_launch(struct mv_cesa_tdma_chain *chain,
u32 flags)
{
struct mv_cesa_tdma_desc *tdma;
tdma = mv_cesa_dma_add_desc(chain, flags);
if (IS_ERR(tdma))
return PTR_ERR(tdma);
return 0;
}
int mv_cesa_dma_add_dummy_end(struct mv_cesa_tdma_chain *chain, u32 flags)
{
struct mv_cesa_tdma_desc *tdma;
tdma = mv_cesa_dma_add_desc(chain, flags);
if (IS_ERR(tdma))
return PTR_ERR(tdma);
tdma->byte_cnt = BIT(31);
return 0;
}
int mv_cesa_dma_add_op_transfers(struct mv_cesa_tdma_chain *chain,
struct mv_cesa_dma_iter *dma_iter,
struct mv_cesa_sg_dma_iter *sgiter,
gfp_t gfp_flags)
{
u32 flags = sgiter->dir == DMA_TO_DEVICE ?
CESA_TDMA_DST_IN_SRAM : CESA_TDMA_SRC_IN_SRAM;
unsigned int len;
do {
dma_addr_t dst, src;
int ret;
len = mv_cesa_req_dma_iter_transfer_len(dma_iter, sgiter);
if (sgiter->dir == DMA_TO_DEVICE) {
dst = CESA_SA_DATA_SRAM_OFFSET + sgiter->op_offset;
src = sg_dma_address(sgiter->sg) + sgiter->offset;
} else {
dst = sg_dma_address(sgiter->sg) + sgiter->offset;
src = CESA_SA_DATA_SRAM_OFFSET + sgiter->op_offset;
}
ret = mv_cesa_dma_add_data_transfer(chain, dst, src, len,
flags, gfp_flags);
if (ret)
return ret;
} while (mv_cesa_req_dma_iter_next_transfer(dma_iter, sgiter, len));
return 0;
}