linux/drivers/dma/ste_dma40_ll.c
Lee Jones 43f2e1a3be dmaengine: ste_dma40: Convert data_width from register bit format to value
When a DMA client requests and configures a DMA channel, it requests
data_width in Bytes. The DMA40 driver then swiftly converts it over to
the necessary register bit value. Unfortunately, for any subsequent
calculations we have to shift '1' by the bit pattern (1 << data_width)
times to make any sense of it.

This patch flips the semantics on its head and only converts the value
to its respective register bit pattern when writing to registers. This
way we can use the true data_width (in Bytes) value.

Cc: Dan Williams <djbw@fb.com>
Cc: Per Forlin <per.forlin@stericsson.com>
Cc: Rabin Vincent <rabin@rab.in>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-06-04 11:12:09 +02:00

447 lines
11 KiB
C

/*
* Copyright (C) ST-Ericsson SA 2007-2010
* Author: Per Forlin <per.forlin@stericsson.com> for ST-Ericsson
* Author: Jonas Aaberg <jonas.aberg@stericsson.com> for ST-Ericsson
* License terms: GNU General Public License (GPL) version 2
*/
#include <linux/kernel.h>
#include <linux/platform_data/dma-ste-dma40.h>
#include "ste_dma40_ll.h"
u8 d40_width_to_bits(enum dma_slave_buswidth width)
{
if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
return STEDMA40_ESIZE_8_BIT;
else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
return STEDMA40_ESIZE_16_BIT;
else if (width == DMA_SLAVE_BUSWIDTH_8_BYTES)
return STEDMA40_ESIZE_64_BIT;
else
return STEDMA40_ESIZE_32_BIT;
}
/* Sets up proper LCSP1 and LCSP3 register for a logical channel */
void d40_log_cfg(struct stedma40_chan_cfg *cfg,
u32 *lcsp1, u32 *lcsp3)
{
u32 l3 = 0; /* dst */
u32 l1 = 0; /* src */
/* src is mem? -> increase address pos */
if (cfg->dir == DMA_MEM_TO_DEV ||
cfg->dir == DMA_MEM_TO_MEM)
l1 |= BIT(D40_MEM_LCSP1_SCFG_INCR_POS);
/* dst is mem? -> increase address pos */
if (cfg->dir == DMA_DEV_TO_MEM ||
cfg->dir == DMA_MEM_TO_MEM)
l3 |= BIT(D40_MEM_LCSP3_DCFG_INCR_POS);
/* src is hw? -> master port 1 */
if (cfg->dir == DMA_DEV_TO_MEM ||
cfg->dir == DMA_DEV_TO_DEV)
l1 |= BIT(D40_MEM_LCSP1_SCFG_MST_POS);
/* dst is hw? -> master port 1 */
if (cfg->dir == DMA_MEM_TO_DEV ||
cfg->dir == DMA_DEV_TO_DEV)
l3 |= BIT(D40_MEM_LCSP3_DCFG_MST_POS);
l3 |= BIT(D40_MEM_LCSP3_DCFG_EIM_POS);
l3 |= cfg->dst_info.psize << D40_MEM_LCSP3_DCFG_PSIZE_POS;
l3 |= d40_width_to_bits(cfg->dst_info.data_width)
<< D40_MEM_LCSP3_DCFG_ESIZE_POS;
l1 |= BIT(D40_MEM_LCSP1_SCFG_EIM_POS);
l1 |= cfg->src_info.psize << D40_MEM_LCSP1_SCFG_PSIZE_POS;
l1 |= d40_width_to_bits(cfg->src_info.data_width)
<< D40_MEM_LCSP1_SCFG_ESIZE_POS;
*lcsp1 = l1;
*lcsp3 = l3;
}
void d40_phy_cfg(struct stedma40_chan_cfg *cfg, u32 *src_cfg, u32 *dst_cfg)
{
u32 src = 0;
u32 dst = 0;
if ((cfg->dir == DMA_DEV_TO_MEM) ||
(cfg->dir == DMA_DEV_TO_DEV)) {
/* Set master port to 1 */
src |= BIT(D40_SREG_CFG_MST_POS);
src |= D40_TYPE_TO_EVENT(cfg->dev_type);
if (cfg->src_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
src |= BIT(D40_SREG_CFG_PHY_TM_POS);
else
src |= 3 << D40_SREG_CFG_PHY_TM_POS;
}
if ((cfg->dir == DMA_MEM_TO_DEV) ||
(cfg->dir == DMA_DEV_TO_DEV)) {
/* Set master port to 1 */
dst |= BIT(D40_SREG_CFG_MST_POS);
dst |= D40_TYPE_TO_EVENT(cfg->dev_type);
if (cfg->dst_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
dst |= BIT(D40_SREG_CFG_PHY_TM_POS);
else
dst |= 3 << D40_SREG_CFG_PHY_TM_POS;
}
/* Interrupt on end of transfer for destination */
dst |= BIT(D40_SREG_CFG_TIM_POS);
/* Generate interrupt on error */
src |= BIT(D40_SREG_CFG_EIM_POS);
dst |= BIT(D40_SREG_CFG_EIM_POS);
/* PSIZE */
if (cfg->src_info.psize != STEDMA40_PSIZE_PHY_1) {
src |= BIT(D40_SREG_CFG_PHY_PEN_POS);
src |= cfg->src_info.psize << D40_SREG_CFG_PSIZE_POS;
}
if (cfg->dst_info.psize != STEDMA40_PSIZE_PHY_1) {
dst |= BIT(D40_SREG_CFG_PHY_PEN_POS);
dst |= cfg->dst_info.psize << D40_SREG_CFG_PSIZE_POS;
}
/* Element size */
src |= d40_width_to_bits(cfg->src_info.data_width)
<< D40_SREG_CFG_ESIZE_POS;
dst |= d40_width_to_bits(cfg->dst_info.data_width)
<< D40_SREG_CFG_ESIZE_POS;
/* Set the priority bit to high for the physical channel */
if (cfg->high_priority) {
src |= BIT(D40_SREG_CFG_PRI_POS);
dst |= BIT(D40_SREG_CFG_PRI_POS);
}
if (cfg->src_info.big_endian)
src |= BIT(D40_SREG_CFG_LBE_POS);
if (cfg->dst_info.big_endian)
dst |= BIT(D40_SREG_CFG_LBE_POS);
*src_cfg = src;
*dst_cfg = dst;
}
static int d40_phy_fill_lli(struct d40_phy_lli *lli,
dma_addr_t data,
u32 data_size,
dma_addr_t next_lli,
u32 reg_cfg,
struct stedma40_half_channel_info *info,
unsigned int flags)
{
bool addr_inc = flags & LLI_ADDR_INC;
bool term_int = flags & LLI_TERM_INT;
unsigned int data_width = info->data_width;
int psize = info->psize;
int num_elems;
if (psize == STEDMA40_PSIZE_PHY_1)
num_elems = 1;
else
num_elems = 2 << psize;
/* Must be aligned */
if (!IS_ALIGNED(data, data_width))
return -EINVAL;
/* Transfer size can't be smaller than (num_elms * elem_size) */
if (data_size < num_elems * data_width)
return -EINVAL;
/* The number of elements. IE now many chunks */
lli->reg_elt = (data_size / data_width) << D40_SREG_ELEM_PHY_ECNT_POS;
/*
* Distance to next element sized entry.
* Usually the size of the element unless you want gaps.
*/
if (addr_inc)
lli->reg_elt |= data_width << D40_SREG_ELEM_PHY_EIDX_POS;
/* Where the data is */
lli->reg_ptr = data;
lli->reg_cfg = reg_cfg;
/* If this scatter list entry is the last one, no next link */
if (next_lli == 0)
lli->reg_lnk = BIT(D40_SREG_LNK_PHY_TCP_POS);
else
lli->reg_lnk = next_lli;
/* Set/clear interrupt generation on this link item.*/
if (term_int)
lli->reg_cfg |= BIT(D40_SREG_CFG_TIM_POS);
else
lli->reg_cfg &= ~BIT(D40_SREG_CFG_TIM_POS);
/* Post link */
lli->reg_lnk |= 0 << D40_SREG_LNK_PHY_PRE_POS;
return 0;
}
static int d40_seg_size(int size, int data_width1, int data_width2)
{
u32 max_w = max(data_width1, data_width2);
u32 min_w = min(data_width1, data_width2);
u32 seg_max = ALIGN(STEDMA40_MAX_SEG_SIZE * min_w, max_w);
if (seg_max > STEDMA40_MAX_SEG_SIZE)
seg_max -= max_w;
if (size <= seg_max)
return size;
if (size <= 2 * seg_max)
return ALIGN(size / 2, max_w);
return seg_max;
}
static struct d40_phy_lli *
d40_phy_buf_to_lli(struct d40_phy_lli *lli, dma_addr_t addr, u32 size,
dma_addr_t lli_phys, dma_addr_t first_phys, u32 reg_cfg,
struct stedma40_half_channel_info *info,
struct stedma40_half_channel_info *otherinfo,
unsigned long flags)
{
bool lastlink = flags & LLI_LAST_LINK;
bool addr_inc = flags & LLI_ADDR_INC;
bool term_int = flags & LLI_TERM_INT;
bool cyclic = flags & LLI_CYCLIC;
int err;
dma_addr_t next = lli_phys;
int size_rest = size;
int size_seg = 0;
/*
* This piece may be split up based on d40_seg_size(); we only want the
* term int on the last part.
*/
if (term_int)
flags &= ~LLI_TERM_INT;
do {
size_seg = d40_seg_size(size_rest, info->data_width,
otherinfo->data_width);
size_rest -= size_seg;
if (size_rest == 0 && term_int)
flags |= LLI_TERM_INT;
if (size_rest == 0 && lastlink)
next = cyclic ? first_phys : 0;
else
next = ALIGN(next + sizeof(struct d40_phy_lli),
D40_LLI_ALIGN);
err = d40_phy_fill_lli(lli, addr, size_seg, next,
reg_cfg, info, flags);
if (err)
goto err;
lli++;
if (addr_inc)
addr += size_seg;
} while (size_rest);
return lli;
err:
return NULL;
}
int d40_phy_sg_to_lli(struct scatterlist *sg,
int sg_len,
dma_addr_t target,
struct d40_phy_lli *lli_sg,
dma_addr_t lli_phys,
u32 reg_cfg,
struct stedma40_half_channel_info *info,
struct stedma40_half_channel_info *otherinfo,
unsigned long flags)
{
int total_size = 0;
int i;
struct scatterlist *current_sg = sg;
struct d40_phy_lli *lli = lli_sg;
dma_addr_t l_phys = lli_phys;
if (!target)
flags |= LLI_ADDR_INC;
for_each_sg(sg, current_sg, sg_len, i) {
dma_addr_t sg_addr = sg_dma_address(current_sg);
unsigned int len = sg_dma_len(current_sg);
dma_addr_t dst = target ?: sg_addr;
total_size += sg_dma_len(current_sg);
if (i == sg_len - 1)
flags |= LLI_TERM_INT | LLI_LAST_LINK;
l_phys = ALIGN(lli_phys + (lli - lli_sg) *
sizeof(struct d40_phy_lli), D40_LLI_ALIGN);
lli = d40_phy_buf_to_lli(lli, dst, len, l_phys, lli_phys,
reg_cfg, info, otherinfo, flags);
if (lli == NULL)
return -EINVAL;
}
return total_size;
}
/* DMA logical lli operations */
static void d40_log_lli_link(struct d40_log_lli *lli_dst,
struct d40_log_lli *lli_src,
int next, unsigned int flags)
{
bool interrupt = flags & LLI_TERM_INT;
u32 slos = 0;
u32 dlos = 0;
if (next != -EINVAL) {
slos = next * 2;
dlos = next * 2 + 1;
}
if (interrupt) {
lli_dst->lcsp13 |= D40_MEM_LCSP1_SCFG_TIM_MASK;
lli_dst->lcsp13 |= D40_MEM_LCSP3_DTCP_MASK;
}
lli_src->lcsp13 = (lli_src->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
(slos << D40_MEM_LCSP1_SLOS_POS);
lli_dst->lcsp13 = (lli_dst->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
(dlos << D40_MEM_LCSP1_SLOS_POS);
}
void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
struct d40_log_lli *lli_dst,
struct d40_log_lli *lli_src,
int next, unsigned int flags)
{
d40_log_lli_link(lli_dst, lli_src, next, flags);
writel_relaxed(lli_src->lcsp02, &lcpa[0].lcsp0);
writel_relaxed(lli_src->lcsp13, &lcpa[0].lcsp1);
writel_relaxed(lli_dst->lcsp02, &lcpa[0].lcsp2);
writel_relaxed(lli_dst->lcsp13, &lcpa[0].lcsp3);
}
void d40_log_lli_lcla_write(struct d40_log_lli *lcla,
struct d40_log_lli *lli_dst,
struct d40_log_lli *lli_src,
int next, unsigned int flags)
{
d40_log_lli_link(lli_dst, lli_src, next, flags);
writel_relaxed(lli_src->lcsp02, &lcla[0].lcsp02);
writel_relaxed(lli_src->lcsp13, &lcla[0].lcsp13);
writel_relaxed(lli_dst->lcsp02, &lcla[1].lcsp02);
writel_relaxed(lli_dst->lcsp13, &lcla[1].lcsp13);
}
static void d40_log_fill_lli(struct d40_log_lli *lli,
dma_addr_t data, u32 data_size,
u32 reg_cfg,
u32 data_width,
unsigned int flags)
{
bool addr_inc = flags & LLI_ADDR_INC;
lli->lcsp13 = reg_cfg;
/* The number of elements to transfer */
lli->lcsp02 = ((data_size / data_width) <<
D40_MEM_LCSP0_ECNT_POS) & D40_MEM_LCSP0_ECNT_MASK;
BUG_ON((data_size / data_width) > STEDMA40_MAX_SEG_SIZE);
/* 16 LSBs address of the current element */
lli->lcsp02 |= data & D40_MEM_LCSP0_SPTR_MASK;
/* 16 MSBs address of the current element */
lli->lcsp13 |= data & D40_MEM_LCSP1_SPTR_MASK;
if (addr_inc)
lli->lcsp13 |= D40_MEM_LCSP1_SCFG_INCR_MASK;
}
static struct d40_log_lli *d40_log_buf_to_lli(struct d40_log_lli *lli_sg,
dma_addr_t addr,
int size,
u32 lcsp13, /* src or dst*/
u32 data_width1,
u32 data_width2,
unsigned int flags)
{
bool addr_inc = flags & LLI_ADDR_INC;
struct d40_log_lli *lli = lli_sg;
int size_rest = size;
int size_seg = 0;
do {
size_seg = d40_seg_size(size_rest, data_width1, data_width2);
size_rest -= size_seg;
d40_log_fill_lli(lli,
addr,
size_seg,
lcsp13, data_width1,
flags);
if (addr_inc)
addr += size_seg;
lli++;
} while (size_rest);
return lli;
}
int d40_log_sg_to_lli(struct scatterlist *sg,
int sg_len,
dma_addr_t dev_addr,
struct d40_log_lli *lli_sg,
u32 lcsp13, /* src or dst*/
u32 data_width1, u32 data_width2)
{
int total_size = 0;
struct scatterlist *current_sg = sg;
int i;
struct d40_log_lli *lli = lli_sg;
unsigned long flags = 0;
if (!dev_addr)
flags |= LLI_ADDR_INC;
for_each_sg(sg, current_sg, sg_len, i) {
dma_addr_t sg_addr = sg_dma_address(current_sg);
unsigned int len = sg_dma_len(current_sg);
dma_addr_t addr = dev_addr ?: sg_addr;
total_size += sg_dma_len(current_sg);
lli = d40_log_buf_to_lli(lli, addr, len,
lcsp13,
data_width1,
data_width2,
flags);
}
return total_size;
}