linux/drivers/dma/stm32-mdma.c

1728 lines
49 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) STMicroelectronics SA 2017
* Author(s): M'boumba Cedric Madianga <cedric.madianga@gmail.com>
* Pierre-Yves Mordret <pierre-yves.mordret@st.com>
*
* Driver for STM32 MDMA controller
*
* Inspired by stm32-dma.c and dma-jz4780.c
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/iopoll.h>
#include <linux/jiffies.h>
#include <linux/list.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/slab.h>
#include "virt-dma.h"
/* MDMA Generic getter/setter */
#define STM32_MDMA_SHIFT(n) (ffs(n) - 1)
#define STM32_MDMA_SET(n, mask) (((n) << STM32_MDMA_SHIFT(mask)) & \
(mask))
#define STM32_MDMA_GET(n, mask) (((n) & (mask)) >> \
STM32_MDMA_SHIFT(mask))
#define STM32_MDMA_GISR0 0x0000 /* MDMA Int Status Reg 1 */
#define STM32_MDMA_GISR1 0x0004 /* MDMA Int Status Reg 2 */
/* MDMA Channel x interrupt/status register */
#define STM32_MDMA_CISR(x) (0x40 + 0x40 * (x)) /* x = 0..62 */
#define STM32_MDMA_CISR_CRQA BIT(16)
#define STM32_MDMA_CISR_TCIF BIT(4)
#define STM32_MDMA_CISR_BTIF BIT(3)
#define STM32_MDMA_CISR_BRTIF BIT(2)
#define STM32_MDMA_CISR_CTCIF BIT(1)
#define STM32_MDMA_CISR_TEIF BIT(0)
/* MDMA Channel x interrupt flag clear register */
#define STM32_MDMA_CIFCR(x) (0x44 + 0x40 * (x))
#define STM32_MDMA_CIFCR_CLTCIF BIT(4)
#define STM32_MDMA_CIFCR_CBTIF BIT(3)
#define STM32_MDMA_CIFCR_CBRTIF BIT(2)
#define STM32_MDMA_CIFCR_CCTCIF BIT(1)
#define STM32_MDMA_CIFCR_CTEIF BIT(0)
#define STM32_MDMA_CIFCR_CLEAR_ALL (STM32_MDMA_CIFCR_CLTCIF \
| STM32_MDMA_CIFCR_CBTIF \
| STM32_MDMA_CIFCR_CBRTIF \
| STM32_MDMA_CIFCR_CCTCIF \
| STM32_MDMA_CIFCR_CTEIF)
/* MDMA Channel x error status register */
#define STM32_MDMA_CESR(x) (0x48 + 0x40 * (x))
#define STM32_MDMA_CESR_BSE BIT(11)
#define STM32_MDMA_CESR_ASR BIT(10)
#define STM32_MDMA_CESR_TEMD BIT(9)
#define STM32_MDMA_CESR_TELD BIT(8)
#define STM32_MDMA_CESR_TED BIT(7)
#define STM32_MDMA_CESR_TEA_MASK GENMASK(6, 0)
/* MDMA Channel x control register */
#define STM32_MDMA_CCR(x) (0x4C + 0x40 * (x))
#define STM32_MDMA_CCR_SWRQ BIT(16)
#define STM32_MDMA_CCR_WEX BIT(14)
#define STM32_MDMA_CCR_HEX BIT(13)
#define STM32_MDMA_CCR_BEX BIT(12)
#define STM32_MDMA_CCR_PL_MASK GENMASK(7, 6)
#define STM32_MDMA_CCR_PL(n) STM32_MDMA_SET(n, \
STM32_MDMA_CCR_PL_MASK)
#define STM32_MDMA_CCR_TCIE BIT(5)
#define STM32_MDMA_CCR_BTIE BIT(4)
#define STM32_MDMA_CCR_BRTIE BIT(3)
#define STM32_MDMA_CCR_CTCIE BIT(2)
#define STM32_MDMA_CCR_TEIE BIT(1)
#define STM32_MDMA_CCR_EN BIT(0)
#define STM32_MDMA_CCR_IRQ_MASK (STM32_MDMA_CCR_TCIE \
| STM32_MDMA_CCR_BTIE \
| STM32_MDMA_CCR_BRTIE \
| STM32_MDMA_CCR_CTCIE \
| STM32_MDMA_CCR_TEIE)
/* MDMA Channel x transfer configuration register */
#define STM32_MDMA_CTCR(x) (0x50 + 0x40 * (x))
#define STM32_MDMA_CTCR_BWM BIT(31)
#define STM32_MDMA_CTCR_SWRM BIT(30)
#define STM32_MDMA_CTCR_TRGM_MSK GENMASK(29, 28)
#define STM32_MDMA_CTCR_TRGM(n) STM32_MDMA_SET((n), \
STM32_MDMA_CTCR_TRGM_MSK)
#define STM32_MDMA_CTCR_TRGM_GET(n) STM32_MDMA_GET((n), \
STM32_MDMA_CTCR_TRGM_MSK)
#define STM32_MDMA_CTCR_PAM_MASK GENMASK(27, 26)
#define STM32_MDMA_CTCR_PAM(n) STM32_MDMA_SET(n, \
STM32_MDMA_CTCR_PAM_MASK)
#define STM32_MDMA_CTCR_PKE BIT(25)
#define STM32_MDMA_CTCR_TLEN_MSK GENMASK(24, 18)
#define STM32_MDMA_CTCR_TLEN(n) STM32_MDMA_SET((n), \
STM32_MDMA_CTCR_TLEN_MSK)
#define STM32_MDMA_CTCR_TLEN_GET(n) STM32_MDMA_GET((n), \
STM32_MDMA_CTCR_TLEN_MSK)
#define STM32_MDMA_CTCR_LEN2_MSK GENMASK(25, 18)
#define STM32_MDMA_CTCR_LEN2(n) STM32_MDMA_SET((n), \
STM32_MDMA_CTCR_LEN2_MSK)
#define STM32_MDMA_CTCR_LEN2_GET(n) STM32_MDMA_GET((n), \
STM32_MDMA_CTCR_LEN2_MSK)
#define STM32_MDMA_CTCR_DBURST_MASK GENMASK(17, 15)
#define STM32_MDMA_CTCR_DBURST(n) STM32_MDMA_SET(n, \
STM32_MDMA_CTCR_DBURST_MASK)
#define STM32_MDMA_CTCR_SBURST_MASK GENMASK(14, 12)
#define STM32_MDMA_CTCR_SBURST(n) STM32_MDMA_SET(n, \
STM32_MDMA_CTCR_SBURST_MASK)
#define STM32_MDMA_CTCR_DINCOS_MASK GENMASK(11, 10)
#define STM32_MDMA_CTCR_DINCOS(n) STM32_MDMA_SET((n), \
STM32_MDMA_CTCR_DINCOS_MASK)
#define STM32_MDMA_CTCR_SINCOS_MASK GENMASK(9, 8)
#define STM32_MDMA_CTCR_SINCOS(n) STM32_MDMA_SET((n), \
STM32_MDMA_CTCR_SINCOS_MASK)
#define STM32_MDMA_CTCR_DSIZE_MASK GENMASK(7, 6)
#define STM32_MDMA_CTCR_DSIZE(n) STM32_MDMA_SET(n, \
STM32_MDMA_CTCR_DSIZE_MASK)
#define STM32_MDMA_CTCR_SSIZE_MASK GENMASK(5, 4)
#define STM32_MDMA_CTCR_SSIZE(n) STM32_MDMA_SET(n, \
STM32_MDMA_CTCR_SSIZE_MASK)
#define STM32_MDMA_CTCR_DINC_MASK GENMASK(3, 2)
#define STM32_MDMA_CTCR_DINC(n) STM32_MDMA_SET((n), \
STM32_MDMA_CTCR_DINC_MASK)
#define STM32_MDMA_CTCR_SINC_MASK GENMASK(1, 0)
#define STM32_MDMA_CTCR_SINC(n) STM32_MDMA_SET((n), \
STM32_MDMA_CTCR_SINC_MASK)
#define STM32_MDMA_CTCR_CFG_MASK (STM32_MDMA_CTCR_SINC_MASK \
| STM32_MDMA_CTCR_DINC_MASK \
| STM32_MDMA_CTCR_SINCOS_MASK \
| STM32_MDMA_CTCR_DINCOS_MASK \
| STM32_MDMA_CTCR_LEN2_MSK \
| STM32_MDMA_CTCR_TRGM_MSK)
/* MDMA Channel x block number of data register */
#define STM32_MDMA_CBNDTR(x) (0x54 + 0x40 * (x))
#define STM32_MDMA_CBNDTR_BRC_MK GENMASK(31, 20)
#define STM32_MDMA_CBNDTR_BRC(n) STM32_MDMA_SET(n, \
STM32_MDMA_CBNDTR_BRC_MK)
#define STM32_MDMA_CBNDTR_BRC_GET(n) STM32_MDMA_GET((n), \
STM32_MDMA_CBNDTR_BRC_MK)
#define STM32_MDMA_CBNDTR_BRDUM BIT(19)
#define STM32_MDMA_CBNDTR_BRSUM BIT(18)
#define STM32_MDMA_CBNDTR_BNDT_MASK GENMASK(16, 0)
#define STM32_MDMA_CBNDTR_BNDT(n) STM32_MDMA_SET(n, \
STM32_MDMA_CBNDTR_BNDT_MASK)
/* MDMA Channel x source address register */
#define STM32_MDMA_CSAR(x) (0x58 + 0x40 * (x))
/* MDMA Channel x destination address register */
#define STM32_MDMA_CDAR(x) (0x5C + 0x40 * (x))
/* MDMA Channel x block repeat address update register */
#define STM32_MDMA_CBRUR(x) (0x60 + 0x40 * (x))
#define STM32_MDMA_CBRUR_DUV_MASK GENMASK(31, 16)
#define STM32_MDMA_CBRUR_DUV(n) STM32_MDMA_SET(n, \
STM32_MDMA_CBRUR_DUV_MASK)
#define STM32_MDMA_CBRUR_SUV_MASK GENMASK(15, 0)
#define STM32_MDMA_CBRUR_SUV(n) STM32_MDMA_SET(n, \
STM32_MDMA_CBRUR_SUV_MASK)
/* MDMA Channel x link address register */
#define STM32_MDMA_CLAR(x) (0x64 + 0x40 * (x))
/* MDMA Channel x trigger and bus selection register */
#define STM32_MDMA_CTBR(x) (0x68 + 0x40 * (x))
#define STM32_MDMA_CTBR_DBUS BIT(17)
#define STM32_MDMA_CTBR_SBUS BIT(16)
#define STM32_MDMA_CTBR_TSEL_MASK GENMASK(7, 0)
#define STM32_MDMA_CTBR_TSEL(n) STM32_MDMA_SET(n, \
STM32_MDMA_CTBR_TSEL_MASK)
/* MDMA Channel x mask address register */
#define STM32_MDMA_CMAR(x) (0x70 + 0x40 * (x))
/* MDMA Channel x mask data register */
#define STM32_MDMA_CMDR(x) (0x74 + 0x40 * (x))
#define STM32_MDMA_MAX_BUF_LEN 128
#define STM32_MDMA_MAX_BLOCK_LEN 65536
#define STM32_MDMA_MAX_CHANNELS 63
#define STM32_MDMA_MAX_REQUESTS 256
#define STM32_MDMA_MAX_BURST 128
#define STM32_MDMA_VERY_HIGH_PRIORITY 0x11
enum stm32_mdma_trigger_mode {
STM32_MDMA_BUFFER,
STM32_MDMA_BLOCK,
STM32_MDMA_BLOCK_REP,
STM32_MDMA_LINKED_LIST,
};
enum stm32_mdma_width {
STM32_MDMA_BYTE,
STM32_MDMA_HALF_WORD,
STM32_MDMA_WORD,
STM32_MDMA_DOUBLE_WORD,
};
enum stm32_mdma_inc_mode {
STM32_MDMA_FIXED = 0,
STM32_MDMA_INC = 2,
STM32_MDMA_DEC = 3,
};
struct stm32_mdma_chan_config {
u32 request;
u32 priority_level;
u32 transfer_config;
u32 mask_addr;
u32 mask_data;
};
struct stm32_mdma_hwdesc {
u32 ctcr;
u32 cbndtr;
u32 csar;
u32 cdar;
u32 cbrur;
u32 clar;
u32 ctbr;
u32 dummy;
u32 cmar;
u32 cmdr;
} __aligned(64);
struct stm32_mdma_desc_node {
struct stm32_mdma_hwdesc *hwdesc;
dma_addr_t hwdesc_phys;
};
struct stm32_mdma_desc {
struct virt_dma_desc vdesc;
u32 ccr;
bool cyclic;
u32 count;
struct stm32_mdma_desc_node node[];
};
struct stm32_mdma_chan {
struct virt_dma_chan vchan;
struct dma_pool *desc_pool;
u32 id;
struct stm32_mdma_desc *desc;
u32 curr_hwdesc;
struct dma_slave_config dma_config;
struct stm32_mdma_chan_config chan_config;
bool busy;
u32 mem_burst;
u32 mem_width;
};
struct stm32_mdma_device {
struct dma_device ddev;
void __iomem *base;
struct clk *clk;
int irq;
struct reset_control *rst;
u32 nr_channels;
u32 nr_requests;
u32 nr_ahb_addr_masks;
struct stm32_mdma_chan chan[STM32_MDMA_MAX_CHANNELS];
u32 ahb_addr_masks[];
};
static struct stm32_mdma_device *stm32_mdma_get_dev(
struct stm32_mdma_chan *chan)
{
return container_of(chan->vchan.chan.device, struct stm32_mdma_device,
ddev);
}
static struct stm32_mdma_chan *to_stm32_mdma_chan(struct dma_chan *c)
{
return container_of(c, struct stm32_mdma_chan, vchan.chan);
}
static struct stm32_mdma_desc *to_stm32_mdma_desc(struct virt_dma_desc *vdesc)
{
return container_of(vdesc, struct stm32_mdma_desc, vdesc);
}
static struct device *chan2dev(struct stm32_mdma_chan *chan)
{
return &chan->vchan.chan.dev->device;
}
static struct device *mdma2dev(struct stm32_mdma_device *mdma_dev)
{
return mdma_dev->ddev.dev;
}
static u32 stm32_mdma_read(struct stm32_mdma_device *dmadev, u32 reg)
{
return readl_relaxed(dmadev->base + reg);
}
static void stm32_mdma_write(struct stm32_mdma_device *dmadev, u32 reg, u32 val)
{
writel_relaxed(val, dmadev->base + reg);
}
static void stm32_mdma_set_bits(struct stm32_mdma_device *dmadev, u32 reg,
u32 mask)
{
void __iomem *addr = dmadev->base + reg;
writel_relaxed(readl_relaxed(addr) | mask, addr);
}
static void stm32_mdma_clr_bits(struct stm32_mdma_device *dmadev, u32 reg,
u32 mask)
{
void __iomem *addr = dmadev->base + reg;
writel_relaxed(readl_relaxed(addr) & ~mask, addr);
}
static struct stm32_mdma_desc *stm32_mdma_alloc_desc(
struct stm32_mdma_chan *chan, u32 count)
{
struct stm32_mdma_desc *desc;
int i;
desc = kzalloc(offsetof(typeof(*desc), node[count]), GFP_NOWAIT);
if (!desc)
return NULL;
for (i = 0; i < count; i++) {
desc->node[i].hwdesc =
dma_pool_alloc(chan->desc_pool, GFP_NOWAIT,
&desc->node[i].hwdesc_phys);
if (!desc->node[i].hwdesc)
goto err;
}
desc->count = count;
return desc;
err:
dev_err(chan2dev(chan), "Failed to allocate descriptor\n");
while (--i >= 0)
dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
desc->node[i].hwdesc_phys);
kfree(desc);
return NULL;
}
static void stm32_mdma_desc_free(struct virt_dma_desc *vdesc)
{
struct stm32_mdma_desc *desc = to_stm32_mdma_desc(vdesc);
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(vdesc->tx.chan);
int i;
for (i = 0; i < desc->count; i++)
dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
desc->node[i].hwdesc_phys);
kfree(desc);
}
static int stm32_mdma_get_width(struct stm32_mdma_chan *chan,
enum dma_slave_buswidth width)
{
switch (width) {
case DMA_SLAVE_BUSWIDTH_1_BYTE:
case DMA_SLAVE_BUSWIDTH_2_BYTES:
case DMA_SLAVE_BUSWIDTH_4_BYTES:
case DMA_SLAVE_BUSWIDTH_8_BYTES:
return ffs(width) - 1;
default:
dev_err(chan2dev(chan), "Dma bus width %i not supported\n",
width);
return -EINVAL;
}
}
static enum dma_slave_buswidth stm32_mdma_get_max_width(dma_addr_t addr,
u32 buf_len, u32 tlen)
{
enum dma_slave_buswidth max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
for (max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
max_width > DMA_SLAVE_BUSWIDTH_1_BYTE;
max_width >>= 1) {
/*
* Address and buffer length both have to be aligned on
* bus width
*/
if ((((buf_len | addr) & (max_width - 1)) == 0) &&
tlen >= max_width)
break;
}
return max_width;
}
static u32 stm32_mdma_get_best_burst(u32 buf_len, u32 tlen, u32 max_burst,
enum dma_slave_buswidth width)
{
u32 best_burst;
best_burst = min((u32)1 << __ffs(tlen | buf_len),
max_burst * width) / width;
return (best_burst > 0) ? best_burst : 1;
}
static int stm32_mdma_disable_chan(struct stm32_mdma_chan *chan)
{
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
u32 ccr, cisr, id, reg;
int ret;
id = chan->id;
reg = STM32_MDMA_CCR(id);
/* Disable interrupts */
stm32_mdma_clr_bits(dmadev, reg, STM32_MDMA_CCR_IRQ_MASK);
ccr = stm32_mdma_read(dmadev, reg);
if (ccr & STM32_MDMA_CCR_EN) {
stm32_mdma_clr_bits(dmadev, reg, STM32_MDMA_CCR_EN);
/* Ensure that any ongoing transfer has been completed */
ret = readl_relaxed_poll_timeout_atomic(
dmadev->base + STM32_MDMA_CISR(id), cisr,
(cisr & STM32_MDMA_CISR_CTCIF), 10, 1000);
if (ret) {
dev_err(chan2dev(chan), "%s: timeout!\n", __func__);
return -EBUSY;
}
}
return 0;
}
static void stm32_mdma_stop(struct stm32_mdma_chan *chan)
{
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
u32 status;
int ret;
/* Disable DMA */
ret = stm32_mdma_disable_chan(chan);
if (ret < 0)
return;
/* Clear interrupt status if it is there */
status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id));
if (status) {
dev_dbg(chan2dev(chan), "%s(): clearing interrupt: 0x%08x\n",
__func__, status);
stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(chan->id), status);
}
chan->busy = false;
}
static void stm32_mdma_set_bus(struct stm32_mdma_device *dmadev, u32 *ctbr,
u32 ctbr_mask, u32 src_addr)
{
u32 mask;
int i;
/* Check if memory device is on AHB or AXI */
*ctbr &= ~ctbr_mask;
mask = src_addr & 0xF0000000;
for (i = 0; i < dmadev->nr_ahb_addr_masks; i++) {
if (mask == dmadev->ahb_addr_masks[i]) {
*ctbr |= ctbr_mask;
break;
}
}
}
static int stm32_mdma_set_xfer_param(struct stm32_mdma_chan *chan,
enum dma_transfer_direction direction,
u32 *mdma_ccr, u32 *mdma_ctcr,
u32 *mdma_ctbr, dma_addr_t addr,
u32 buf_len)
{
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
struct stm32_mdma_chan_config *chan_config = &chan->chan_config;
enum dma_slave_buswidth src_addr_width, dst_addr_width;
phys_addr_t src_addr, dst_addr;
int src_bus_width, dst_bus_width;
u32 src_maxburst, dst_maxburst, src_best_burst, dst_best_burst;
u32 ccr, ctcr, ctbr, tlen;
src_addr_width = chan->dma_config.src_addr_width;
dst_addr_width = chan->dma_config.dst_addr_width;
src_maxburst = chan->dma_config.src_maxburst;
dst_maxburst = chan->dma_config.dst_maxburst;
ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id));
ctcr = stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id));
ctbr = stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id));
/* Enable HW request mode */
ctcr &= ~STM32_MDMA_CTCR_SWRM;
/* Set DINC, SINC, DINCOS, SINCOS, TRGM and TLEN retrieve from DT */
ctcr &= ~STM32_MDMA_CTCR_CFG_MASK;
ctcr |= chan_config->transfer_config & STM32_MDMA_CTCR_CFG_MASK;
/*
* For buffer transfer length (TLEN) we have to set
* the number of bytes - 1 in CTCR register
*/
tlen = STM32_MDMA_CTCR_LEN2_GET(ctcr);
ctcr &= ~STM32_MDMA_CTCR_LEN2_MSK;
ctcr |= STM32_MDMA_CTCR_TLEN((tlen - 1));
/* Disable Pack Enable */
ctcr &= ~STM32_MDMA_CTCR_PKE;
/* Check burst size constraints */
if (src_maxburst * src_addr_width > STM32_MDMA_MAX_BURST ||
dst_maxburst * dst_addr_width > STM32_MDMA_MAX_BURST) {
dev_err(chan2dev(chan),
"burst size * bus width higher than %d bytes\n",
STM32_MDMA_MAX_BURST);
return -EINVAL;
}
if ((!is_power_of_2(src_maxburst) && src_maxburst > 0) ||
(!is_power_of_2(dst_maxburst) && dst_maxburst > 0)) {
dev_err(chan2dev(chan), "burst size must be a power of 2\n");
return -EINVAL;
}
/*
* Configure channel control:
* - Clear SW request as in this case this is a HW one
* - Clear WEX, HEX and BEX bits
* - Set priority level
*/
ccr &= ~(STM32_MDMA_CCR_SWRQ | STM32_MDMA_CCR_WEX | STM32_MDMA_CCR_HEX |
STM32_MDMA_CCR_BEX | STM32_MDMA_CCR_PL_MASK);
ccr |= STM32_MDMA_CCR_PL(chan_config->priority_level);
/* Configure Trigger selection */
ctbr &= ~STM32_MDMA_CTBR_TSEL_MASK;
ctbr |= STM32_MDMA_CTBR_TSEL(chan_config->request);
switch (direction) {
case DMA_MEM_TO_DEV:
dst_addr = chan->dma_config.dst_addr;
/* Set device data size */
dst_bus_width = stm32_mdma_get_width(chan, dst_addr_width);
if (dst_bus_width < 0)
return dst_bus_width;
ctcr &= ~STM32_MDMA_CTCR_DSIZE_MASK;
ctcr |= STM32_MDMA_CTCR_DSIZE(dst_bus_width);
/* Set device burst value */
dst_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
dst_maxburst,
dst_addr_width);
chan->mem_burst = dst_best_burst;
ctcr &= ~STM32_MDMA_CTCR_DBURST_MASK;
ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst)));
/* Set memory data size */
src_addr_width = stm32_mdma_get_max_width(addr, buf_len, tlen);
chan->mem_width = src_addr_width;
src_bus_width = stm32_mdma_get_width(chan, src_addr_width);
if (src_bus_width < 0)
return src_bus_width;
ctcr &= ~STM32_MDMA_CTCR_SSIZE_MASK |
STM32_MDMA_CTCR_SINCOS_MASK;
ctcr |= STM32_MDMA_CTCR_SSIZE(src_bus_width) |
STM32_MDMA_CTCR_SINCOS(src_bus_width);
/* Set memory burst value */
src_maxburst = STM32_MDMA_MAX_BUF_LEN / src_addr_width;
src_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
src_maxburst,
src_addr_width);
chan->mem_burst = src_best_burst;
ctcr &= ~STM32_MDMA_CTCR_SBURST_MASK;
ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst)));
/* Select bus */
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS,
dst_addr);
if (dst_bus_width != src_bus_width)
ctcr |= STM32_MDMA_CTCR_PKE;
/* Set destination address */
stm32_mdma_write(dmadev, STM32_MDMA_CDAR(chan->id), dst_addr);
break;
case DMA_DEV_TO_MEM:
src_addr = chan->dma_config.src_addr;
/* Set device data size */
src_bus_width = stm32_mdma_get_width(chan, src_addr_width);
if (src_bus_width < 0)
return src_bus_width;
ctcr &= ~STM32_MDMA_CTCR_SSIZE_MASK;
ctcr |= STM32_MDMA_CTCR_SSIZE(src_bus_width);
/* Set device burst value */
src_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
src_maxburst,
src_addr_width);
ctcr &= ~STM32_MDMA_CTCR_SBURST_MASK;
ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst)));
/* Set memory data size */
dst_addr_width = stm32_mdma_get_max_width(addr, buf_len, tlen);
chan->mem_width = dst_addr_width;
dst_bus_width = stm32_mdma_get_width(chan, dst_addr_width);
if (dst_bus_width < 0)
return dst_bus_width;
ctcr &= ~(STM32_MDMA_CTCR_DSIZE_MASK |
STM32_MDMA_CTCR_DINCOS_MASK);
ctcr |= STM32_MDMA_CTCR_DSIZE(dst_bus_width) |
STM32_MDMA_CTCR_DINCOS(dst_bus_width);
/* Set memory burst value */
dst_maxburst = STM32_MDMA_MAX_BUF_LEN / dst_addr_width;
dst_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
dst_maxburst,
dst_addr_width);
ctcr &= ~STM32_MDMA_CTCR_DBURST_MASK;
ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst)));
/* Select bus */
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS,
src_addr);
if (dst_bus_width != src_bus_width)
ctcr |= STM32_MDMA_CTCR_PKE;
/* Set source address */
stm32_mdma_write(dmadev, STM32_MDMA_CSAR(chan->id), src_addr);
break;
default:
dev_err(chan2dev(chan), "Dma direction is not supported\n");
return -EINVAL;
}
*mdma_ccr = ccr;
*mdma_ctcr = ctcr;
*mdma_ctbr = ctbr;
return 0;
}
static void stm32_mdma_dump_hwdesc(struct stm32_mdma_chan *chan,
struct stm32_mdma_desc_node *node)
{
dev_dbg(chan2dev(chan), "hwdesc: %pad\n", &node->hwdesc_phys);
dev_dbg(chan2dev(chan), "CTCR: 0x%08x\n", node->hwdesc->ctcr);
dev_dbg(chan2dev(chan), "CBNDTR: 0x%08x\n", node->hwdesc->cbndtr);
dev_dbg(chan2dev(chan), "CSAR: 0x%08x\n", node->hwdesc->csar);
dev_dbg(chan2dev(chan), "CDAR: 0x%08x\n", node->hwdesc->cdar);
dev_dbg(chan2dev(chan), "CBRUR: 0x%08x\n", node->hwdesc->cbrur);
dev_dbg(chan2dev(chan), "CLAR: 0x%08x\n", node->hwdesc->clar);
dev_dbg(chan2dev(chan), "CTBR: 0x%08x\n", node->hwdesc->ctbr);
dev_dbg(chan2dev(chan), "CMAR: 0x%08x\n", node->hwdesc->cmar);
dev_dbg(chan2dev(chan), "CMDR: 0x%08x\n\n", node->hwdesc->cmdr);
}
static void stm32_mdma_setup_hwdesc(struct stm32_mdma_chan *chan,
struct stm32_mdma_desc *desc,
enum dma_transfer_direction dir, u32 count,
dma_addr_t src_addr, dma_addr_t dst_addr,
u32 len, u32 ctcr, u32 ctbr, bool is_last,
bool is_first, bool is_cyclic)
{
struct stm32_mdma_chan_config *config = &chan->chan_config;
struct stm32_mdma_hwdesc *hwdesc;
u32 next = count + 1;
hwdesc = desc->node[count].hwdesc;
hwdesc->ctcr = ctcr;
hwdesc->cbndtr &= ~(STM32_MDMA_CBNDTR_BRC_MK |
STM32_MDMA_CBNDTR_BRDUM |
STM32_MDMA_CBNDTR_BRSUM |
STM32_MDMA_CBNDTR_BNDT_MASK);
hwdesc->cbndtr |= STM32_MDMA_CBNDTR_BNDT(len);
hwdesc->csar = src_addr;
hwdesc->cdar = dst_addr;
hwdesc->cbrur = 0;
hwdesc->ctbr = ctbr;
hwdesc->cmar = config->mask_addr;
hwdesc->cmdr = config->mask_data;
if (is_last) {
if (is_cyclic)
hwdesc->clar = desc->node[0].hwdesc_phys;
else
hwdesc->clar = 0;
} else {
hwdesc->clar = desc->node[next].hwdesc_phys;
}
stm32_mdma_dump_hwdesc(chan, &desc->node[count]);
}
static int stm32_mdma_setup_xfer(struct stm32_mdma_chan *chan,
struct stm32_mdma_desc *desc,
struct scatterlist *sgl, u32 sg_len,
enum dma_transfer_direction direction)
{
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
struct dma_slave_config *dma_config = &chan->dma_config;
struct scatterlist *sg;
dma_addr_t src_addr, dst_addr;
u32 ccr, ctcr, ctbr;
int i, ret = 0;
for_each_sg(sgl, sg, sg_len, i) {
if (sg_dma_len(sg) > STM32_MDMA_MAX_BLOCK_LEN) {
dev_err(chan2dev(chan), "Invalid block len\n");
return -EINVAL;
}
if (direction == DMA_MEM_TO_DEV) {
src_addr = sg_dma_address(sg);
dst_addr = dma_config->dst_addr;
ret = stm32_mdma_set_xfer_param(chan, direction, &ccr,
&ctcr, &ctbr, src_addr,
sg_dma_len(sg));
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS,
src_addr);
} else {
src_addr = dma_config->src_addr;
dst_addr = sg_dma_address(sg);
ret = stm32_mdma_set_xfer_param(chan, direction, &ccr,
&ctcr, &ctbr, dst_addr,
sg_dma_len(sg));
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS,
dst_addr);
}
if (ret < 0)
return ret;
stm32_mdma_setup_hwdesc(chan, desc, direction, i, src_addr,
dst_addr, sg_dma_len(sg), ctcr, ctbr,
i == sg_len - 1, i == 0, false);
}
/* Enable interrupts */
ccr &= ~STM32_MDMA_CCR_IRQ_MASK;
ccr |= STM32_MDMA_CCR_TEIE | STM32_MDMA_CCR_CTCIE;
if (sg_len > 1)
ccr |= STM32_MDMA_CCR_BTIE;
desc->ccr = ccr;
return 0;
}
static struct dma_async_tx_descriptor *
stm32_mdma_prep_slave_sg(struct dma_chan *c, struct scatterlist *sgl,
u32 sg_len, enum dma_transfer_direction direction,
unsigned long flags, void *context)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
struct stm32_mdma_desc *desc;
int i, ret;
/*
* Once DMA is in setup cyclic mode the channel we cannot assign this
* channel anymore. The DMA channel needs to be aborted or terminated
* for allowing another request.
*/
if (chan->desc && chan->desc->cyclic) {
dev_err(chan2dev(chan),
"Request not allowed when dma in cyclic mode\n");
return NULL;
}
desc = stm32_mdma_alloc_desc(chan, sg_len);
if (!desc)
return NULL;
ret = stm32_mdma_setup_xfer(chan, desc, sgl, sg_len, direction);
if (ret < 0)
goto xfer_setup_err;
desc->cyclic = false;
return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
xfer_setup_err:
for (i = 0; i < desc->count; i++)
dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
desc->node[i].hwdesc_phys);
kfree(desc);
return NULL;
}
static struct dma_async_tx_descriptor *
stm32_mdma_prep_dma_cyclic(struct dma_chan *c, dma_addr_t buf_addr,
size_t buf_len, size_t period_len,
enum dma_transfer_direction direction,
unsigned long flags)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
struct dma_slave_config *dma_config = &chan->dma_config;
struct stm32_mdma_desc *desc;
dma_addr_t src_addr, dst_addr;
u32 ccr, ctcr, ctbr, count;
int i, ret;
/*
* Once DMA is in setup cyclic mode the channel we cannot assign this
* channel anymore. The DMA channel needs to be aborted or terminated
* for allowing another request.
*/
if (chan->desc && chan->desc->cyclic) {
dev_err(chan2dev(chan),
"Request not allowed when dma in cyclic mode\n");
return NULL;
}
if (!buf_len || !period_len || period_len > STM32_MDMA_MAX_BLOCK_LEN) {
dev_err(chan2dev(chan), "Invalid buffer/period len\n");
return NULL;
}
if (buf_len % period_len) {
dev_err(chan2dev(chan), "buf_len not multiple of period_len\n");
return NULL;
}
count = buf_len / period_len;
desc = stm32_mdma_alloc_desc(chan, count);
if (!desc)
return NULL;
/* Select bus */
if (direction == DMA_MEM_TO_DEV) {
src_addr = buf_addr;
ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr,
&ctbr, src_addr, period_len);
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS,
src_addr);
} else {
dst_addr = buf_addr;
ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr,
&ctbr, dst_addr, period_len);
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS,
dst_addr);
}
if (ret < 0)
goto xfer_setup_err;
/* Enable interrupts */
ccr &= ~STM32_MDMA_CCR_IRQ_MASK;
ccr |= STM32_MDMA_CCR_TEIE | STM32_MDMA_CCR_CTCIE | STM32_MDMA_CCR_BTIE;
desc->ccr = ccr;
/* Configure hwdesc list */
for (i = 0; i < count; i++) {
if (direction == DMA_MEM_TO_DEV) {
src_addr = buf_addr + i * period_len;
dst_addr = dma_config->dst_addr;
} else {
src_addr = dma_config->src_addr;
dst_addr = buf_addr + i * period_len;
}
stm32_mdma_setup_hwdesc(chan, desc, direction, i, src_addr,
dst_addr, period_len, ctcr, ctbr,
i == count - 1, i == 0, true);
}
desc->cyclic = true;
return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
xfer_setup_err:
for (i = 0; i < desc->count; i++)
dma_pool_free(chan->desc_pool, desc->node[i].hwdesc,
desc->node[i].hwdesc_phys);
kfree(desc);
return NULL;
}
static struct dma_async_tx_descriptor *
stm32_mdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest, dma_addr_t src,
size_t len, unsigned long flags)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
enum dma_slave_buswidth max_width;
struct stm32_mdma_desc *desc;
struct stm32_mdma_hwdesc *hwdesc;
u32 ccr, ctcr, ctbr, cbndtr, count, max_burst, mdma_burst;
u32 best_burst, tlen;
size_t xfer_count, offset;
int src_bus_width, dst_bus_width;
int i;
/*
* Once DMA is in setup cyclic mode the channel we cannot assign this
* channel anymore. The DMA channel needs to be aborted or terminated
* to allow another request
*/
if (chan->desc && chan->desc->cyclic) {
dev_err(chan2dev(chan),
"Request not allowed when dma in cyclic mode\n");
return NULL;
}
count = DIV_ROUND_UP(len, STM32_MDMA_MAX_BLOCK_LEN);
desc = stm32_mdma_alloc_desc(chan, count);
if (!desc)
return NULL;
ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id));
ctcr = stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id));
ctbr = stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id));
cbndtr = stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id));
/* Enable sw req, some interrupts and clear other bits */
ccr &= ~(STM32_MDMA_CCR_WEX | STM32_MDMA_CCR_HEX |
STM32_MDMA_CCR_BEX | STM32_MDMA_CCR_PL_MASK |
STM32_MDMA_CCR_IRQ_MASK);
ccr |= STM32_MDMA_CCR_TEIE;
/* Enable SW request mode, dest/src inc and clear other bits */
ctcr &= ~(STM32_MDMA_CTCR_BWM | STM32_MDMA_CTCR_TRGM_MSK |
STM32_MDMA_CTCR_PAM_MASK | STM32_MDMA_CTCR_PKE |
STM32_MDMA_CTCR_TLEN_MSK | STM32_MDMA_CTCR_DBURST_MASK |
STM32_MDMA_CTCR_SBURST_MASK | STM32_MDMA_CTCR_DINCOS_MASK |
STM32_MDMA_CTCR_SINCOS_MASK | STM32_MDMA_CTCR_DSIZE_MASK |
STM32_MDMA_CTCR_SSIZE_MASK | STM32_MDMA_CTCR_DINC_MASK |
STM32_MDMA_CTCR_SINC_MASK);
ctcr |= STM32_MDMA_CTCR_SWRM | STM32_MDMA_CTCR_SINC(STM32_MDMA_INC) |
STM32_MDMA_CTCR_DINC(STM32_MDMA_INC);
/* Reset HW request */
ctbr &= ~STM32_MDMA_CTBR_TSEL_MASK;
/* Select bus */
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS, src);
stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS, dest);
/* Clear CBNDTR registers */
cbndtr &= ~(STM32_MDMA_CBNDTR_BRC_MK | STM32_MDMA_CBNDTR_BRDUM |
STM32_MDMA_CBNDTR_BRSUM | STM32_MDMA_CBNDTR_BNDT_MASK);
if (len <= STM32_MDMA_MAX_BLOCK_LEN) {
cbndtr |= STM32_MDMA_CBNDTR_BNDT(len);
if (len <= STM32_MDMA_MAX_BUF_LEN) {
/* Setup a buffer transfer */
ccr |= STM32_MDMA_CCR_TCIE | STM32_MDMA_CCR_CTCIE;
ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BUFFER);
} else {
/* Setup a block transfer */
ccr |= STM32_MDMA_CCR_BTIE | STM32_MDMA_CCR_CTCIE;
ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BLOCK);
}
tlen = STM32_MDMA_MAX_BUF_LEN;
ctcr |= STM32_MDMA_CTCR_TLEN((tlen - 1));
/* Set source best burst size */
max_width = stm32_mdma_get_max_width(src, len, tlen);
src_bus_width = stm32_mdma_get_width(chan, max_width);
max_burst = tlen / max_width;
best_burst = stm32_mdma_get_best_burst(len, tlen, max_burst,
max_width);
mdma_burst = ilog2(best_burst);
ctcr |= STM32_MDMA_CTCR_SBURST(mdma_burst) |
STM32_MDMA_CTCR_SSIZE(src_bus_width) |
STM32_MDMA_CTCR_SINCOS(src_bus_width);
/* Set destination best burst size */
max_width = stm32_mdma_get_max_width(dest, len, tlen);
dst_bus_width = stm32_mdma_get_width(chan, max_width);
max_burst = tlen / max_width;
best_burst = stm32_mdma_get_best_burst(len, tlen, max_burst,
max_width);
mdma_burst = ilog2(best_burst);
ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) |
STM32_MDMA_CTCR_DSIZE(dst_bus_width) |
STM32_MDMA_CTCR_DINCOS(dst_bus_width);
if (dst_bus_width != src_bus_width)
ctcr |= STM32_MDMA_CTCR_PKE;
/* Prepare hardware descriptor */
hwdesc = desc->node[0].hwdesc;
hwdesc->ctcr = ctcr;
hwdesc->cbndtr = cbndtr;
hwdesc->csar = src;
hwdesc->cdar = dest;
hwdesc->cbrur = 0;
hwdesc->clar = 0;
hwdesc->ctbr = ctbr;
hwdesc->cmar = 0;
hwdesc->cmdr = 0;
stm32_mdma_dump_hwdesc(chan, &desc->node[0]);
} else {
/* Setup a LLI transfer */
ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_LINKED_LIST) |
STM32_MDMA_CTCR_TLEN((STM32_MDMA_MAX_BUF_LEN - 1));
ccr |= STM32_MDMA_CCR_BTIE | STM32_MDMA_CCR_CTCIE;
tlen = STM32_MDMA_MAX_BUF_LEN;
for (i = 0, offset = 0; offset < len;
i++, offset += xfer_count) {
xfer_count = min_t(size_t, len - offset,
STM32_MDMA_MAX_BLOCK_LEN);
/* Set source best burst size */
max_width = stm32_mdma_get_max_width(src, len, tlen);
src_bus_width = stm32_mdma_get_width(chan, max_width);
max_burst = tlen / max_width;
best_burst = stm32_mdma_get_best_burst(len, tlen,
max_burst,
max_width);
mdma_burst = ilog2(best_burst);
ctcr |= STM32_MDMA_CTCR_SBURST(mdma_burst) |
STM32_MDMA_CTCR_SSIZE(src_bus_width) |
STM32_MDMA_CTCR_SINCOS(src_bus_width);
/* Set destination best burst size */
max_width = stm32_mdma_get_max_width(dest, len, tlen);
dst_bus_width = stm32_mdma_get_width(chan, max_width);
max_burst = tlen / max_width;
best_burst = stm32_mdma_get_best_burst(len, tlen,
max_burst,
max_width);
mdma_burst = ilog2(best_burst);
ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) |
STM32_MDMA_CTCR_DSIZE(dst_bus_width) |
STM32_MDMA_CTCR_DINCOS(dst_bus_width);
if (dst_bus_width != src_bus_width)
ctcr |= STM32_MDMA_CTCR_PKE;
/* Prepare hardware descriptor */
stm32_mdma_setup_hwdesc(chan, desc, DMA_MEM_TO_MEM, i,
src + offset, dest + offset,
xfer_count, ctcr, ctbr,
i == count - 1, i == 0, false);
}
}
desc->ccr = ccr;
desc->cyclic = false;
return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
}
static void stm32_mdma_dump_reg(struct stm32_mdma_chan *chan)
{
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
dev_dbg(chan2dev(chan), "CCR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)));
dev_dbg(chan2dev(chan), "CTCR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id)));
dev_dbg(chan2dev(chan), "CBNDTR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id)));
dev_dbg(chan2dev(chan), "CSAR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CSAR(chan->id)));
dev_dbg(chan2dev(chan), "CDAR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CDAR(chan->id)));
dev_dbg(chan2dev(chan), "CBRUR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CBRUR(chan->id)));
dev_dbg(chan2dev(chan), "CLAR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CLAR(chan->id)));
dev_dbg(chan2dev(chan), "CTBR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id)));
dev_dbg(chan2dev(chan), "CMAR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CMAR(chan->id)));
dev_dbg(chan2dev(chan), "CMDR: 0x%08x\n",
stm32_mdma_read(dmadev, STM32_MDMA_CMDR(chan->id)));
}
static void stm32_mdma_start_transfer(struct stm32_mdma_chan *chan)
{
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
struct virt_dma_desc *vdesc;
struct stm32_mdma_hwdesc *hwdesc;
u32 id = chan->id;
u32 status, reg;
vdesc = vchan_next_desc(&chan->vchan);
if (!vdesc) {
chan->desc = NULL;
return;
}
chan->desc = to_stm32_mdma_desc(vdesc);
hwdesc = chan->desc->node[0].hwdesc;
chan->curr_hwdesc = 0;
stm32_mdma_write(dmadev, STM32_MDMA_CCR(id), chan->desc->ccr);
stm32_mdma_write(dmadev, STM32_MDMA_CTCR(id), hwdesc->ctcr);
stm32_mdma_write(dmadev, STM32_MDMA_CBNDTR(id), hwdesc->cbndtr);
stm32_mdma_write(dmadev, STM32_MDMA_CSAR(id), hwdesc->csar);
stm32_mdma_write(dmadev, STM32_MDMA_CDAR(id), hwdesc->cdar);
stm32_mdma_write(dmadev, STM32_MDMA_CBRUR(id), hwdesc->cbrur);
stm32_mdma_write(dmadev, STM32_MDMA_CLAR(id), hwdesc->clar);
stm32_mdma_write(dmadev, STM32_MDMA_CTBR(id), hwdesc->ctbr);
stm32_mdma_write(dmadev, STM32_MDMA_CMAR(id), hwdesc->cmar);
stm32_mdma_write(dmadev, STM32_MDMA_CMDR(id), hwdesc->cmdr);
/* Clear interrupt status if it is there */
status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(id));
if (status)
stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(id), status);
stm32_mdma_dump_reg(chan);
/* Start DMA */
stm32_mdma_set_bits(dmadev, STM32_MDMA_CCR(id), STM32_MDMA_CCR_EN);
/* Set SW request in case of MEM2MEM transfer */
if (hwdesc->ctcr & STM32_MDMA_CTCR_SWRM) {
reg = STM32_MDMA_CCR(id);
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_SWRQ);
}
chan->busy = true;
dev_dbg(chan2dev(chan), "vchan %pK: started\n", &chan->vchan);
}
static void stm32_mdma_issue_pending(struct dma_chan *c)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
unsigned long flags;
spin_lock_irqsave(&chan->vchan.lock, flags);
if (!vchan_issue_pending(&chan->vchan))
goto end;
dev_dbg(chan2dev(chan), "vchan %pK: issued\n", &chan->vchan);
if (!chan->desc && !chan->busy)
stm32_mdma_start_transfer(chan);
end:
spin_unlock_irqrestore(&chan->vchan.lock, flags);
}
static int stm32_mdma_pause(struct dma_chan *c)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
unsigned long flags;
int ret;
spin_lock_irqsave(&chan->vchan.lock, flags);
ret = stm32_mdma_disable_chan(chan);
spin_unlock_irqrestore(&chan->vchan.lock, flags);
if (!ret)
dev_dbg(chan2dev(chan), "vchan %pK: pause\n", &chan->vchan);
return ret;
}
static int stm32_mdma_resume(struct dma_chan *c)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
struct stm32_mdma_hwdesc *hwdesc;
unsigned long flags;
u32 status, reg;
hwdesc = chan->desc->node[chan->curr_hwdesc].hwdesc;
spin_lock_irqsave(&chan->vchan.lock, flags);
/* Re-configure control register */
stm32_mdma_write(dmadev, STM32_MDMA_CCR(chan->id), chan->desc->ccr);
/* Clear interrupt status if it is there */
status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id));
if (status)
stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(chan->id), status);
stm32_mdma_dump_reg(chan);
/* Re-start DMA */
reg = STM32_MDMA_CCR(chan->id);
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_EN);
/* Set SW request in case of MEM2MEM transfer */
if (hwdesc->ctcr & STM32_MDMA_CTCR_SWRM)
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_SWRQ);
spin_unlock_irqrestore(&chan->vchan.lock, flags);
dev_dbg(chan2dev(chan), "vchan %pK: resume\n", &chan->vchan);
return 0;
}
static int stm32_mdma_terminate_all(struct dma_chan *c)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
unsigned long flags;
LIST_HEAD(head);
spin_lock_irqsave(&chan->vchan.lock, flags);
if (chan->busy) {
stm32_mdma_stop(chan);
chan->desc = NULL;
}
vchan_get_all_descriptors(&chan->vchan, &head);
spin_unlock_irqrestore(&chan->vchan.lock, flags);
vchan_dma_desc_free_list(&chan->vchan, &head);
return 0;
}
static void stm32_mdma_synchronize(struct dma_chan *c)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
vchan_synchronize(&chan->vchan);
}
static int stm32_mdma_slave_config(struct dma_chan *c,
struct dma_slave_config *config)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
memcpy(&chan->dma_config, config, sizeof(*config));
return 0;
}
static size_t stm32_mdma_desc_residue(struct stm32_mdma_chan *chan,
struct stm32_mdma_desc *desc,
u32 curr_hwdesc)
{
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
struct stm32_mdma_hwdesc *hwdesc = desc->node[0].hwdesc;
u32 cbndtr, residue, modulo, burst_size;
int i;
residue = 0;
for (i = curr_hwdesc + 1; i < desc->count; i++) {
hwdesc = desc->node[i].hwdesc;
residue += STM32_MDMA_CBNDTR_BNDT(hwdesc->cbndtr);
}
cbndtr = stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id));
residue += cbndtr & STM32_MDMA_CBNDTR_BNDT_MASK;
if (!chan->mem_burst)
return residue;
burst_size = chan->mem_burst * chan->mem_width;
modulo = residue % burst_size;
if (modulo)
residue = residue - modulo + burst_size;
return residue;
}
static enum dma_status stm32_mdma_tx_status(struct dma_chan *c,
dma_cookie_t cookie,
struct dma_tx_state *state)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
struct virt_dma_desc *vdesc;
enum dma_status status;
unsigned long flags;
u32 residue = 0;
status = dma_cookie_status(c, cookie, state);
if ((status == DMA_COMPLETE) || (!state))
return status;
spin_lock_irqsave(&chan->vchan.lock, flags);
vdesc = vchan_find_desc(&chan->vchan, cookie);
if (chan->desc && cookie == chan->desc->vdesc.tx.cookie)
residue = stm32_mdma_desc_residue(chan, chan->desc,
chan->curr_hwdesc);
else if (vdesc)
residue = stm32_mdma_desc_residue(chan,
to_stm32_mdma_desc(vdesc), 0);
dma_set_residue(state, residue);
spin_unlock_irqrestore(&chan->vchan.lock, flags);
return status;
}
static void stm32_mdma_xfer_end(struct stm32_mdma_chan *chan)
{
list_del(&chan->desc->vdesc.node);
vchan_cookie_complete(&chan->desc->vdesc);
chan->desc = NULL;
chan->busy = false;
/* Start the next transfer if this driver has a next desc */
stm32_mdma_start_transfer(chan);
}
static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid)
{
struct stm32_mdma_device *dmadev = devid;
struct stm32_mdma_chan *chan = devid;
u32 reg, id, ien, status, flag;
/* Find out which channel generates the interrupt */
status = readl_relaxed(dmadev->base + STM32_MDMA_GISR0);
if (status) {
id = __ffs(status);
} else {
status = readl_relaxed(dmadev->base + STM32_MDMA_GISR1);
if (!status) {
dev_dbg(mdma2dev(dmadev), "spurious it\n");
return IRQ_NONE;
}
id = __ffs(status);
/*
* As GISR0 provides status for channel id from 0 to 31,
* so GISR1 provides status for channel id from 32 to 62
*/
id += 32;
}
chan = &dmadev->chan[id];
if (!chan) {
dev_err(chan2dev(chan), "MDMA channel not initialized\n");
goto exit;
}
/* Handle interrupt for the channel */
spin_lock(&chan->vchan.lock);
status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id));
ien = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id));
ien &= STM32_MDMA_CCR_IRQ_MASK;
ien >>= 1;
if (!(status & ien)) {
spin_unlock(&chan->vchan.lock);
dev_dbg(chan2dev(chan),
"spurious it (status=0x%04x, ien=0x%04x)\n",
status, ien);
return IRQ_NONE;
}
flag = __ffs(status & ien);
reg = STM32_MDMA_CIFCR(chan->id);
switch (1 << flag) {
case STM32_MDMA_CISR_TEIF:
id = chan->id;
status = readl_relaxed(dmadev->base + STM32_MDMA_CESR(id));
dev_err(chan2dev(chan), "Transfer Err: stat=0x%08x\n", status);
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CTEIF);
break;
case STM32_MDMA_CISR_CTCIF:
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CCTCIF);
stm32_mdma_xfer_end(chan);
break;
case STM32_MDMA_CISR_BRTIF:
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBRTIF);
break;
case STM32_MDMA_CISR_BTIF:
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBTIF);
chan->curr_hwdesc++;
if (chan->desc && chan->desc->cyclic) {
if (chan->curr_hwdesc == chan->desc->count)
chan->curr_hwdesc = 0;
vchan_cyclic_callback(&chan->desc->vdesc);
}
break;
case STM32_MDMA_CISR_TCIF:
stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CLTCIF);
break;
default:
dev_err(chan2dev(chan), "it %d unhandled (status=0x%04x)\n",
1 << flag, status);
}
spin_unlock(&chan->vchan.lock);
exit:
return IRQ_HANDLED;
}
static int stm32_mdma_alloc_chan_resources(struct dma_chan *c)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
int ret;
chan->desc_pool = dmam_pool_create(dev_name(&c->dev->device),
c->device->dev,
sizeof(struct stm32_mdma_hwdesc),
__alignof__(struct stm32_mdma_hwdesc),
0);
if (!chan->desc_pool) {
dev_err(chan2dev(chan), "failed to allocate descriptor pool\n");
return -ENOMEM;
}
ret = pm_runtime_get_sync(dmadev->ddev.dev);
if (ret < 0)
return ret;
ret = stm32_mdma_disable_chan(chan);
if (ret < 0)
pm_runtime_put(dmadev->ddev.dev);
return ret;
}
static void stm32_mdma_free_chan_resources(struct dma_chan *c)
{
struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c);
struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
unsigned long flags;
dev_dbg(chan2dev(chan), "Freeing channel %d\n", chan->id);
if (chan->busy) {
spin_lock_irqsave(&chan->vchan.lock, flags);
stm32_mdma_stop(chan);
chan->desc = NULL;
spin_unlock_irqrestore(&chan->vchan.lock, flags);
}
pm_runtime_put(dmadev->ddev.dev);
vchan_free_chan_resources(to_virt_chan(c));
dmam_pool_destroy(chan->desc_pool);
chan->desc_pool = NULL;
}
static struct dma_chan *stm32_mdma_of_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct stm32_mdma_device *dmadev = ofdma->of_dma_data;
struct stm32_mdma_chan *chan;
struct dma_chan *c;
struct stm32_mdma_chan_config config;
if (dma_spec->args_count < 5) {
dev_err(mdma2dev(dmadev), "Bad number of args\n");
return NULL;
}
config.request = dma_spec->args[0];
config.priority_level = dma_spec->args[1];
config.transfer_config = dma_spec->args[2];
config.mask_addr = dma_spec->args[3];
config.mask_data = dma_spec->args[4];
if (config.request >= dmadev->nr_requests) {
dev_err(mdma2dev(dmadev), "Bad request line\n");
return NULL;
}
if (config.priority_level > STM32_MDMA_VERY_HIGH_PRIORITY) {
dev_err(mdma2dev(dmadev), "Priority level not supported\n");
return NULL;
}
c = dma_get_any_slave_channel(&dmadev->ddev);
if (!c) {
dev_err(mdma2dev(dmadev), "No more channels available\n");
return NULL;
}
chan = to_stm32_mdma_chan(c);
chan->chan_config = config;
return c;
}
static const struct of_device_id stm32_mdma_of_match[] = {
{ .compatible = "st,stm32h7-mdma", },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, stm32_mdma_of_match);
static int stm32_mdma_probe(struct platform_device *pdev)
{
struct stm32_mdma_chan *chan;
struct stm32_mdma_device *dmadev;
struct dma_device *dd;
struct device_node *of_node;
struct resource *res;
u32 nr_channels, nr_requests;
int i, count, ret;
of_node = pdev->dev.of_node;
if (!of_node)
return -ENODEV;
ret = device_property_read_u32(&pdev->dev, "dma-channels",
&nr_channels);
if (ret) {
nr_channels = STM32_MDMA_MAX_CHANNELS;
dev_warn(&pdev->dev, "MDMA defaulting on %i channels\n",
nr_channels);
}
ret = device_property_read_u32(&pdev->dev, "dma-requests",
&nr_requests);
if (ret) {
nr_requests = STM32_MDMA_MAX_REQUESTS;
dev_warn(&pdev->dev, "MDMA defaulting on %i request lines\n",
nr_requests);
}
count = device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks",
NULL, 0);
if (count < 0)
count = 0;
dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev) + sizeof(u32) * count,
GFP_KERNEL);
if (!dmadev)
return -ENOMEM;
dmadev->nr_channels = nr_channels;
dmadev->nr_requests = nr_requests;
device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks",
dmadev->ahb_addr_masks,
count);
dmadev->nr_ahb_addr_masks = count;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
dmadev->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(dmadev->base))
return PTR_ERR(dmadev->base);
dmadev->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(dmadev->clk)) {
ret = PTR_ERR(dmadev->clk);
if (ret == -EPROBE_DEFER)
dev_info(&pdev->dev, "Missing controller clock\n");
return ret;
}
ret = clk_prepare_enable(dmadev->clk);
if (ret < 0) {
dev_err(&pdev->dev, "clk_prep_enable error: %d\n", ret);
return ret;
}
dmadev->rst = devm_reset_control_get(&pdev->dev, NULL);
if (!IS_ERR(dmadev->rst)) {
reset_control_assert(dmadev->rst);
udelay(2);
reset_control_deassert(dmadev->rst);
}
dd = &dmadev->ddev;
dma_cap_set(DMA_SLAVE, dd->cap_mask);
dma_cap_set(DMA_PRIVATE, dd->cap_mask);
dma_cap_set(DMA_CYCLIC, dd->cap_mask);
dma_cap_set(DMA_MEMCPY, dd->cap_mask);
dd->device_alloc_chan_resources = stm32_mdma_alloc_chan_resources;
dd->device_free_chan_resources = stm32_mdma_free_chan_resources;
dd->device_tx_status = stm32_mdma_tx_status;
dd->device_issue_pending = stm32_mdma_issue_pending;
dd->device_prep_slave_sg = stm32_mdma_prep_slave_sg;
dd->device_prep_dma_cyclic = stm32_mdma_prep_dma_cyclic;
dd->device_prep_dma_memcpy = stm32_mdma_prep_dma_memcpy;
dd->device_config = stm32_mdma_slave_config;
dd->device_pause = stm32_mdma_pause;
dd->device_resume = stm32_mdma_resume;
dd->device_terminate_all = stm32_mdma_terminate_all;
dd->device_synchronize = stm32_mdma_synchronize;
dd->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
dd->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) |
BIT(DMA_MEM_TO_MEM);
dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
dd->max_burst = STM32_MDMA_MAX_BURST;
dd->dev = &pdev->dev;
INIT_LIST_HEAD(&dd->channels);
for (i = 0; i < dmadev->nr_channels; i++) {
chan = &dmadev->chan[i];
chan->id = i;
chan->vchan.desc_free = stm32_mdma_desc_free;
vchan_init(&chan->vchan, dd);
}
dmadev->irq = platform_get_irq(pdev, 0);
if (dmadev->irq < 0) {
dev_err(&pdev->dev, "failed to get IRQ\n");
return dmadev->irq;
}
ret = devm_request_irq(&pdev->dev, dmadev->irq, stm32_mdma_irq_handler,
0, dev_name(&pdev->dev), dmadev);
if (ret) {
dev_err(&pdev->dev, "failed to request IRQ\n");
return ret;
}
ret = dmaenginem_async_device_register(dd);
if (ret)
return ret;
ret = of_dma_controller_register(of_node, stm32_mdma_of_xlate, dmadev);
if (ret < 0) {
dev_err(&pdev->dev,
"STM32 MDMA DMA OF registration failed %d\n", ret);
goto err_unregister;
}
platform_set_drvdata(pdev, dmadev);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
pm_runtime_get_noresume(&pdev->dev);
pm_runtime_put(&pdev->dev);
dev_info(&pdev->dev, "STM32 MDMA driver registered\n");
return 0;
err_unregister:
return ret;
}
#ifdef CONFIG_PM
static int stm32_mdma_runtime_suspend(struct device *dev)
{
struct stm32_mdma_device *dmadev = dev_get_drvdata(dev);
clk_disable_unprepare(dmadev->clk);
return 0;
}
static int stm32_mdma_runtime_resume(struct device *dev)
{
struct stm32_mdma_device *dmadev = dev_get_drvdata(dev);
int ret;
ret = clk_prepare_enable(dmadev->clk);
if (ret) {
dev_err(dev, "failed to prepare_enable clock\n");
return ret;
}
return 0;
}
#endif
static const struct dev_pm_ops stm32_mdma_pm_ops = {
SET_RUNTIME_PM_OPS(stm32_mdma_runtime_suspend,
stm32_mdma_runtime_resume, NULL)
};
static struct platform_driver stm32_mdma_driver = {
.probe = stm32_mdma_probe,
.driver = {
.name = "stm32-mdma",
.of_match_table = stm32_mdma_of_match,
.pm = &stm32_mdma_pm_ops,
},
};
static int __init stm32_mdma_init(void)
{
return platform_driver_register(&stm32_mdma_driver);
}
subsys_initcall(stm32_mdma_init);
MODULE_DESCRIPTION("Driver for STM32 MDMA controller");
MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>");
MODULE_AUTHOR("Pierre-Yves Mordret <pierre-yves.mordret@st.com>");
MODULE_LICENSE("GPL v2");