blob: 8344b7c91fe356a1f64ca8b5c020b4c68985c83f [file] [log] [blame]
/*
* Ingenic JZ4780 DMA controller
*
* Copyright (c) 2015 Imagination Technologies
* Author: Alex Smith <alex@alex-smith.me.uk>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/clk.h>
#include <linux/dmapool.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "dmaengine.h"
#include "virt-dma.h"
#define JZ_DMA_NR_CHANNELS 32
/* Global registers. */
#define JZ_DMA_REG_DMAC 0x1000
#define JZ_DMA_REG_DIRQP 0x1004
#define JZ_DMA_REG_DDR 0x1008
#define JZ_DMA_REG_DDRS 0x100c
#define JZ_DMA_REG_DMACP 0x101c
#define JZ_DMA_REG_DSIRQP 0x1020
#define JZ_DMA_REG_DSIRQM 0x1024
#define JZ_DMA_REG_DCIRQP 0x1028
#define JZ_DMA_REG_DCIRQM 0x102c
/* Per-channel registers. */
#define JZ_DMA_REG_CHAN(n) (n * 0x20)
#define JZ_DMA_REG_DSA(n) (0x00 + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_REG_DTA(n) (0x04 + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_REG_DTC(n) (0x08 + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_REG_DRT(n) (0x0c + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_REG_DCS(n) (0x10 + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_REG_DCM(n) (0x14 + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_REG_DDA(n) (0x18 + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_REG_DSD(n) (0x1c + JZ_DMA_REG_CHAN(n))
#define JZ_DMA_DMAC_DMAE BIT(0)
#define JZ_DMA_DMAC_AR BIT(2)
#define JZ_DMA_DMAC_HLT BIT(3)
#define JZ_DMA_DMAC_FMSC BIT(31)
#define JZ_DMA_DRT_AUTO 0x8
#define JZ_DMA_DCS_CTE BIT(0)
#define JZ_DMA_DCS_HLT BIT(2)
#define JZ_DMA_DCS_TT BIT(3)
#define JZ_DMA_DCS_AR BIT(4)
#define JZ_DMA_DCS_DES8 BIT(30)
#define JZ_DMA_DCM_LINK BIT(0)
#define JZ_DMA_DCM_TIE BIT(1)
#define JZ_DMA_DCM_STDE BIT(2)
#define JZ_DMA_DCM_TSZ_SHIFT 8
#define JZ_DMA_DCM_TSZ_MASK (0x7 << JZ_DMA_DCM_TSZ_SHIFT)
#define JZ_DMA_DCM_DP_SHIFT 12
#define JZ_DMA_DCM_SP_SHIFT 14
#define JZ_DMA_DCM_DAI BIT(22)
#define JZ_DMA_DCM_SAI BIT(23)
#define JZ_DMA_SIZE_4_BYTE 0x0
#define JZ_DMA_SIZE_1_BYTE 0x1
#define JZ_DMA_SIZE_2_BYTE 0x2
#define JZ_DMA_SIZE_16_BYTE 0x3
#define JZ_DMA_SIZE_32_BYTE 0x4
#define JZ_DMA_SIZE_64_BYTE 0x5
#define JZ_DMA_SIZE_128_BYTE 0x6
#define JZ_DMA_WIDTH_32_BIT 0x0
#define JZ_DMA_WIDTH_8_BIT 0x1
#define JZ_DMA_WIDTH_16_BIT 0x2
#define JZ_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
/**
* struct jz4780_dma_hwdesc - descriptor structure read by the DMA controller.
* @dcm: value for the DCM (channel command) register
* @dsa: source address
* @dta: target address
* @dtc: transfer count (number of blocks of the transfer size specified in DCM
* to transfer) in the low 24 bits, offset of the next descriptor from the
* descriptor base address in the upper 8 bits.
* @sd: target/source stride difference (in stride transfer mode).
* @drt: request type
*/
struct jz4780_dma_hwdesc {
uint32_t dcm;
uint32_t dsa;
uint32_t dta;
uint32_t dtc;
uint32_t sd;
uint32_t drt;
uint32_t reserved[2];
};
/* Size of allocations for hardware descriptor blocks. */
#define JZ_DMA_DESC_BLOCK_SIZE PAGE_SIZE
#define JZ_DMA_MAX_DESC \
(JZ_DMA_DESC_BLOCK_SIZE / sizeof(struct jz4780_dma_hwdesc))
struct jz4780_dma_desc {
struct virt_dma_desc vdesc;
struct jz4780_dma_hwdesc *desc;
dma_addr_t desc_phys;
unsigned int count;
enum dma_transaction_type type;
uint32_t status;
};
struct jz4780_dma_chan {
struct virt_dma_chan vchan;
unsigned int id;
struct dma_pool *desc_pool;
uint32_t transfer_type;
uint32_t transfer_shift;
struct dma_slave_config config;
struct jz4780_dma_desc *desc;
unsigned int curr_hwdesc;
};
struct jz4780_dma_dev {
struct dma_device dma_device;
void __iomem *base;
struct clk *clk;
unsigned int irq;
uint32_t chan_reserved;
struct jz4780_dma_chan chan[JZ_DMA_NR_CHANNELS];
};
struct jz4780_dma_filter_data {
struct device_node *of_node;
uint32_t transfer_type;
int channel;
};
static inline struct jz4780_dma_chan *to_jz4780_dma_chan(struct dma_chan *chan)
{
return container_of(chan, struct jz4780_dma_chan, vchan.chan);
}
static inline struct jz4780_dma_desc *to_jz4780_dma_desc(
struct virt_dma_desc *vdesc)
{
return container_of(vdesc, struct jz4780_dma_desc, vdesc);
}
static inline struct jz4780_dma_dev *jz4780_dma_chan_parent(
struct jz4780_dma_chan *jzchan)
{
return container_of(jzchan->vchan.chan.device, struct jz4780_dma_dev,
dma_device);
}
static inline uint32_t jz4780_dma_readl(struct jz4780_dma_dev *jzdma,
unsigned int reg)
{
return readl(jzdma->base + reg);
}
static inline void jz4780_dma_writel(struct jz4780_dma_dev *jzdma,
unsigned int reg, uint32_t val)
{
writel(val, jzdma->base + reg);
}
static struct jz4780_dma_desc *jz4780_dma_desc_alloc(
struct jz4780_dma_chan *jzchan, unsigned int count,
enum dma_transaction_type type)
{
struct jz4780_dma_desc *desc;
if (count > JZ_DMA_MAX_DESC)
return NULL;
desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
if (!desc)
return NULL;
desc->desc = dma_pool_alloc(jzchan->desc_pool, GFP_NOWAIT,
&desc->desc_phys);
if (!desc->desc) {
kfree(desc);
return NULL;
}
desc->count = count;
desc->type = type;
return desc;
}
static void jz4780_dma_desc_free(struct virt_dma_desc *vdesc)
{
struct jz4780_dma_desc *desc = to_jz4780_dma_desc(vdesc);
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(vdesc->tx.chan);
dma_pool_free(jzchan->desc_pool, desc->desc, desc->desc_phys);
kfree(desc);
}
static uint32_t jz4780_dma_transfer_size(unsigned long val, uint32_t *shift)
{
int ord = ffs(val) - 1;
/*
* 8 byte transfer sizes unsupported so fall back on 4. If it's larger
* than the maximum, just limit it. It is perfectly safe to fall back
* in this way since we won't exceed the maximum burst size supported
* by the device, the only effect is reduced efficiency. This is better
* than refusing to perform the request at all.
*/
if (ord == 3)
ord = 2;
else if (ord > 7)
ord = 7;
*shift = ord;
switch (ord) {
case 0:
return JZ_DMA_SIZE_1_BYTE;
case 1:
return JZ_DMA_SIZE_2_BYTE;
case 2:
return JZ_DMA_SIZE_4_BYTE;
case 4:
return JZ_DMA_SIZE_16_BYTE;
case 5:
return JZ_DMA_SIZE_32_BYTE;
case 6:
return JZ_DMA_SIZE_64_BYTE;
default:
return JZ_DMA_SIZE_128_BYTE;
}
}
static int jz4780_dma_setup_hwdesc(struct jz4780_dma_chan *jzchan,
struct jz4780_dma_hwdesc *desc, dma_addr_t addr, size_t len,
enum dma_transfer_direction direction)
{
struct dma_slave_config *config = &jzchan->config;
uint32_t width, maxburst, tsz;
if (direction == DMA_MEM_TO_DEV) {
desc->dcm = JZ_DMA_DCM_SAI;
desc->dsa = addr;
desc->dta = config->dst_addr;
desc->drt = jzchan->transfer_type;
width = config->dst_addr_width;
maxburst = config->dst_maxburst;
} else {
desc->dcm = JZ_DMA_DCM_DAI;
desc->dsa = config->src_addr;
desc->dta = addr;
desc->drt = jzchan->transfer_type;
width = config->src_addr_width;
maxburst = config->src_maxburst;
}
/*
* This calculates the maximum transfer size that can be used with the
* given address, length, width and maximum burst size. The address
* must be aligned to the transfer size, the total length must be
* divisible by the transfer size, and we must not use more than the
* maximum burst specified by the user.
*/
tsz = jz4780_dma_transfer_size(addr | len | (width * maxburst),
&jzchan->transfer_shift);
switch (width) {
case DMA_SLAVE_BUSWIDTH_1_BYTE:
case DMA_SLAVE_BUSWIDTH_2_BYTES:
break;
case DMA_SLAVE_BUSWIDTH_4_BYTES:
width = JZ_DMA_WIDTH_32_BIT;
break;
default:
return -EINVAL;
}
desc->dcm |= tsz << JZ_DMA_DCM_TSZ_SHIFT;
desc->dcm |= width << JZ_DMA_DCM_SP_SHIFT;
desc->dcm |= width << JZ_DMA_DCM_DP_SHIFT;
desc->dtc = len >> jzchan->transfer_shift;
return 0;
}
static struct dma_async_tx_descriptor *jz4780_dma_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
enum dma_transfer_direction direction, unsigned long flags,
void *context)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
struct jz4780_dma_desc *desc;
unsigned int i;
int err;
desc = jz4780_dma_desc_alloc(jzchan, sg_len, DMA_SLAVE);
if (!desc)
return NULL;
for (i = 0; i < sg_len; i++) {
err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i],
sg_dma_address(&sgl[i]),
sg_dma_len(&sgl[i]),
direction);
if (err < 0)
return NULL;
desc->desc[i].dcm |= JZ_DMA_DCM_TIE;
if (i != (sg_len - 1)) {
/* Automatically proceeed to the next descriptor. */
desc->desc[i].dcm |= JZ_DMA_DCM_LINK;
/*
* The upper 8 bits of the DTC field in the descriptor
* must be set to (offset from descriptor base of next
* descriptor >> 4).
*/
desc->desc[i].dtc |=
(((i + 1) * sizeof(*desc->desc)) >> 4) << 24;
}
}
return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags);
}
static struct dma_async_tx_descriptor *jz4780_dma_prep_dma_cyclic(
struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
size_t period_len, enum dma_transfer_direction direction,
unsigned long flags)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
struct jz4780_dma_desc *desc;
unsigned int periods, i;
int err;
if (buf_len % period_len)
return NULL;
periods = buf_len / period_len;
desc = jz4780_dma_desc_alloc(jzchan, periods, DMA_CYCLIC);
if (!desc)
return NULL;
for (i = 0; i < periods; i++) {
err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i], buf_addr,
period_len, direction);
if (err < 0)
return NULL;
buf_addr += period_len;
/*
* Set the link bit to indicate that the controller should
* automatically proceed to the next descriptor. In
* jz4780_dma_begin(), this will be cleared if we need to issue
* an interrupt after each period.
*/
desc->desc[i].dcm |= JZ_DMA_DCM_TIE | JZ_DMA_DCM_LINK;
/*
* The upper 8 bits of the DTC field in the descriptor must be
* set to (offset from descriptor base of next descriptor >> 4).
* If this is the last descriptor, link it back to the first,
* i.e. leave offset set to 0, otherwise point to the next one.
*/
if (i != (periods - 1)) {
desc->desc[i].dtc |=
(((i + 1) * sizeof(*desc->desc)) >> 4) << 24;
}
}
return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags);
}
struct dma_async_tx_descriptor *jz4780_dma_prep_dma_memcpy(
struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
size_t len, unsigned long flags)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
struct jz4780_dma_desc *desc;
uint32_t tsz;
desc = jz4780_dma_desc_alloc(jzchan, 1, DMA_MEMCPY);
if (!desc)
return NULL;
tsz = jz4780_dma_transfer_size(dest | src | len,
&jzchan->transfer_shift);
desc->desc[0].dsa = src;
desc->desc[0].dta = dest;
desc->desc[0].drt = JZ_DMA_DRT_AUTO;
desc->desc[0].dcm = JZ_DMA_DCM_TIE | JZ_DMA_DCM_SAI | JZ_DMA_DCM_DAI |
tsz << JZ_DMA_DCM_TSZ_SHIFT |
JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_SP_SHIFT |
JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_DP_SHIFT;
desc->desc[0].dtc = len >> jzchan->transfer_shift;
return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags);
}
static void jz4780_dma_begin(struct jz4780_dma_chan *jzchan)
{
struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan);
struct virt_dma_desc *vdesc;
unsigned int i;
dma_addr_t desc_phys;
if (!jzchan->desc) {
vdesc = vchan_next_desc(&jzchan->vchan);
if (!vdesc)
return;
list_del(&vdesc->node);
jzchan->desc = to_jz4780_dma_desc(vdesc);
jzchan->curr_hwdesc = 0;
if (jzchan->desc->type == DMA_CYCLIC && vdesc->tx.callback) {
/*
* The DMA controller doesn't support triggering an
* interrupt after processing each descriptor, only
* after processing an entire terminated list of
* descriptors. For a cyclic DMA setup the list of
* descriptors is not terminated so we can never get an
* interrupt.
*
* If the user requested a callback for a cyclic DMA
* setup then we workaround this hardware limitation
* here by degrading to a set of unlinked descriptors
* which we will submit in sequence in response to the
* completion of processing the previous descriptor.
*/
for (i = 0; i < jzchan->desc->count; i++)
jzchan->desc->desc[i].dcm &= ~JZ_DMA_DCM_LINK;
}
} else {
/*
* There is an existing transfer, therefore this must be one
* for which we unlinked the descriptors above. Advance to the
* next one in the list.
*/
jzchan->curr_hwdesc =
(jzchan->curr_hwdesc + 1) % jzchan->desc->count;
}
/* Use 8-word descriptors. */
jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), JZ_DMA_DCS_DES8);
/* Write descriptor address and initiate descriptor fetch. */
desc_phys = jzchan->desc->desc_phys +
(jzchan->curr_hwdesc * sizeof(*jzchan->desc->desc));
jz4780_dma_writel(jzdma, JZ_DMA_REG_DDA(jzchan->id), desc_phys);
jz4780_dma_writel(jzdma, JZ_DMA_REG_DDRS, BIT(jzchan->id));
/* Enable the channel. */
jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id),
JZ_DMA_DCS_DES8 | JZ_DMA_DCS_CTE);
}
static void jz4780_dma_issue_pending(struct dma_chan *chan)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
unsigned long flags;
spin_lock_irqsave(&jzchan->vchan.lock, flags);
if (vchan_issue_pending(&jzchan->vchan) && !jzchan->desc)
jz4780_dma_begin(jzchan);
spin_unlock_irqrestore(&jzchan->vchan.lock, flags);
}
static int jz4780_dma_terminate_all(struct dma_chan *chan)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan);
unsigned long flags;
LIST_HEAD(head);
spin_lock_irqsave(&jzchan->vchan.lock, flags);
/* Clear the DMA status and stop the transfer. */
jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0);
if (jzchan->desc) {
jz4780_dma_desc_free(&jzchan->desc->vdesc);
jzchan->desc = NULL;
}
vchan_get_all_descriptors(&jzchan->vchan, &head);
spin_unlock_irqrestore(&jzchan->vchan.lock, flags);
vchan_dma_desc_free_list(&jzchan->vchan, &head);
return 0;
}
static int jz4780_dma_config(struct dma_chan *chan,
struct dma_slave_config *config)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
if ((config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
|| (config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES))
return -EINVAL;
/* Copy the reset of the slave configuration, it is used later. */
memcpy(&jzchan->config, config, sizeof(jzchan->config));
return 0;
}
static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan,
struct jz4780_dma_desc *desc, unsigned int next_sg)
{
struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan);
unsigned int residue, count;
unsigned int i;
residue = 0;
for (i = next_sg; i < desc->count; i++)
residue += desc->desc[i].dtc << jzchan->transfer_shift;
if (next_sg != 0) {
count = jz4780_dma_readl(jzdma,
JZ_DMA_REG_DTC(jzchan->id));
residue += count << jzchan->transfer_shift;
}
return residue;
}
static enum dma_status jz4780_dma_tx_status(struct dma_chan *chan,
dma_cookie_t cookie, struct dma_tx_state *txstate)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
struct virt_dma_desc *vdesc;
enum dma_status status;
unsigned long flags;
status = dma_cookie_status(chan, cookie, txstate);
if ((status == DMA_COMPLETE) || (txstate == NULL))
return status;
spin_lock_irqsave(&jzchan->vchan.lock, flags);
vdesc = vchan_find_desc(&jzchan->vchan, cookie);
if (vdesc) {
/* On the issued list, so hasn't been processed yet */
txstate->residue = jz4780_dma_desc_residue(jzchan,
to_jz4780_dma_desc(vdesc), 0);
} else if (cookie == jzchan->desc->vdesc.tx.cookie) {
txstate->residue = jz4780_dma_desc_residue(jzchan, jzchan->desc,
(jzchan->curr_hwdesc + 1) % jzchan->desc->count);
} else
txstate->residue = 0;
if (vdesc && jzchan->desc && vdesc == &jzchan->desc->vdesc
&& jzchan->desc->status & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT))
status = DMA_ERROR;
spin_unlock_irqrestore(&jzchan->vchan.lock, flags);
return status;
}
static void jz4780_dma_chan_irq(struct jz4780_dma_dev *jzdma,
struct jz4780_dma_chan *jzchan)
{
uint32_t dcs;
spin_lock(&jzchan->vchan.lock);
dcs = jz4780_dma_readl(jzdma, JZ_DMA_REG_DCS(jzchan->id));
jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0);
if (dcs & JZ_DMA_DCS_AR) {
dev_warn(&jzchan->vchan.chan.dev->device,
"address error (DCS=0x%x)\n", dcs);
}
if (dcs & JZ_DMA_DCS_HLT) {
dev_warn(&jzchan->vchan.chan.dev->device,
"channel halt (DCS=0x%x)\n", dcs);
}
if (jzchan->desc) {
jzchan->desc->status = dcs;
if ((dcs & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT)) == 0) {
if (jzchan->desc->type == DMA_CYCLIC) {
vchan_cyclic_callback(&jzchan->desc->vdesc);
} else {
vchan_cookie_complete(&jzchan->desc->vdesc);
jzchan->desc = NULL;
}
jz4780_dma_begin(jzchan);
}
} else {
dev_err(&jzchan->vchan.chan.dev->device,
"channel IRQ with no active transfer\n");
}
spin_unlock(&jzchan->vchan.lock);
}
static irqreturn_t jz4780_dma_irq_handler(int irq, void *data)
{
struct jz4780_dma_dev *jzdma = data;
uint32_t pending, dmac;
int i;
pending = jz4780_dma_readl(jzdma, JZ_DMA_REG_DIRQP);
for (i = 0; i < JZ_DMA_NR_CHANNELS; i++) {
if (!(pending & (1<<i)))
continue;
jz4780_dma_chan_irq(jzdma, &jzdma->chan[i]);
}
/* Clear halt and address error status of all channels. */
dmac = jz4780_dma_readl(jzdma, JZ_DMA_REG_DMAC);
dmac &= ~(JZ_DMA_DMAC_HLT | JZ_DMA_DMAC_AR);
jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC, dmac);
/* Clear interrupt pending status. */
jz4780_dma_writel(jzdma, JZ_DMA_REG_DIRQP, 0);
return IRQ_HANDLED;
}
static int jz4780_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
jzchan->desc_pool = dma_pool_create(dev_name(&chan->dev->device),
chan->device->dev,
JZ_DMA_DESC_BLOCK_SIZE,
PAGE_SIZE, 0);
if (!jzchan->desc_pool) {
dev_err(&chan->dev->device,
"failed to allocate descriptor pool\n");
return -ENOMEM;
}
return 0;
}
static void jz4780_dma_free_chan_resources(struct dma_chan *chan)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
vchan_free_chan_resources(&jzchan->vchan);
dma_pool_destroy(jzchan->desc_pool);
jzchan->desc_pool = NULL;
}
static bool jz4780_dma_filter_fn(struct dma_chan *chan, void *param)
{
struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan);
struct jz4780_dma_filter_data *data = param;
if (jzdma->dma_device.dev->of_node != data->of_node)
return false;
if (data->channel > -1) {
if (data->channel != jzchan->id)
return false;
} else if (jzdma->chan_reserved & BIT(jzchan->id)) {
return false;
}
jzchan->transfer_type = data->transfer_type;
return true;
}
static struct dma_chan *jz4780_of_dma_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct jz4780_dma_dev *jzdma = ofdma->of_dma_data;
dma_cap_mask_t mask = jzdma->dma_device.cap_mask;
struct jz4780_dma_filter_data data;
if (dma_spec->args_count != 2)
return NULL;
data.of_node = ofdma->of_node;
data.transfer_type = dma_spec->args[0];
data.channel = dma_spec->args[1];
if (data.channel > -1) {
if (data.channel >= JZ_DMA_NR_CHANNELS) {
dev_err(jzdma->dma_device.dev,
"device requested non-existent channel %u\n",
data.channel);
return NULL;
}
/* Can only select a channel marked as reserved. */
if (!(jzdma->chan_reserved & BIT(data.channel))) {
dev_err(jzdma->dma_device.dev,
"device requested unreserved channel %u\n",
data.channel);
return NULL;
}
jzdma->chan[data.channel].transfer_type = data.transfer_type;
return dma_get_slave_channel(
&jzdma->chan[data.channel].vchan.chan);
} else {
return dma_request_channel(mask, jz4780_dma_filter_fn, &data);
}
}
static int jz4780_dma_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct jz4780_dma_dev *jzdma;
struct jz4780_dma_chan *jzchan;
struct dma_device *dd;
struct resource *res;
int i, ret;
if (!dev->of_node) {
dev_err(dev, "This driver must be probed from devicetree\n");
return -EINVAL;
}
jzdma = devm_kzalloc(dev, sizeof(*jzdma), GFP_KERNEL);
if (!jzdma)
return -ENOMEM;
platform_set_drvdata(pdev, jzdma);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(dev, "failed to get I/O memory\n");
return -EINVAL;
}
jzdma->base = devm_ioremap_resource(dev, res);
if (IS_ERR(jzdma->base))
return PTR_ERR(jzdma->base);
ret = platform_get_irq(pdev, 0);
if (ret < 0) {
dev_err(dev, "failed to get IRQ: %d\n", ret);
return ret;
}
jzdma->irq = ret;
ret = request_irq(jzdma->irq, jz4780_dma_irq_handler, 0, dev_name(dev),
jzdma);
if (ret) {
dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq);
return ret;
}
jzdma->clk = devm_clk_get(dev, NULL);
if (IS_ERR(jzdma->clk)) {
dev_err(dev, "failed to get clock\n");
ret = PTR_ERR(jzdma->clk);
goto err_free_irq;
}
clk_prepare_enable(jzdma->clk);
/* Property is optional, if it doesn't exist the value will remain 0. */
of_property_read_u32_index(dev->of_node, "ingenic,reserved-channels",
0, &jzdma->chan_reserved);
dd = &jzdma->dma_device;
dma_cap_set(DMA_MEMCPY, dd->cap_mask);
dma_cap_set(DMA_SLAVE, dd->cap_mask);
dma_cap_set(DMA_CYCLIC, dd->cap_mask);
dd->dev = dev;
dd->copy_align = DMAENGINE_ALIGN_4_BYTES;
dd->device_alloc_chan_resources = jz4780_dma_alloc_chan_resources;
dd->device_free_chan_resources = jz4780_dma_free_chan_resources;
dd->device_prep_slave_sg = jz4780_dma_prep_slave_sg;
dd->device_prep_dma_cyclic = jz4780_dma_prep_dma_cyclic;
dd->device_prep_dma_memcpy = jz4780_dma_prep_dma_memcpy;
dd->device_config = jz4780_dma_config;
dd->device_terminate_all = jz4780_dma_terminate_all;
dd->device_tx_status = jz4780_dma_tx_status;
dd->device_issue_pending = jz4780_dma_issue_pending;
dd->src_addr_widths = JZ_DMA_BUSWIDTHS;
dd->dst_addr_widths = JZ_DMA_BUSWIDTHS;
dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
/*
* Enable DMA controller, mark all channels as not programmable.
* Also set the FMSC bit - it increases MSC performance, so it makes
* little sense not to enable it.
*/
jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC,
JZ_DMA_DMAC_DMAE | JZ_DMA_DMAC_FMSC);
jz4780_dma_writel(jzdma, JZ_DMA_REG_DMACP, 0);
INIT_LIST_HEAD(&dd->channels);
for (i = 0; i < JZ_DMA_NR_CHANNELS; i++) {
jzchan = &jzdma->chan[i];
jzchan->id = i;
vchan_init(&jzchan->vchan, dd);
jzchan->vchan.desc_free = jz4780_dma_desc_free;
}
ret = dma_async_device_register(dd);
if (ret) {
dev_err(dev, "failed to register device\n");
goto err_disable_clk;
}
/* Register with OF DMA helpers. */
ret = of_dma_controller_register(dev->of_node, jz4780_of_dma_xlate,
jzdma);
if (ret) {
dev_err(dev, "failed to register OF DMA controller\n");
goto err_unregister_dev;
}
dev_info(dev, "JZ4780 DMA controller initialised\n");
return 0;
err_unregister_dev:
dma_async_device_unregister(dd);
err_disable_clk:
clk_disable_unprepare(jzdma->clk);
err_free_irq:
free_irq(jzdma->irq, jzdma);
return ret;
}
static int jz4780_dma_remove(struct platform_device *pdev)
{
struct jz4780_dma_dev *jzdma = platform_get_drvdata(pdev);
int i;
of_dma_controller_free(pdev->dev.of_node);
free_irq(jzdma->irq, jzdma);
for (i = 0; i < JZ_DMA_NR_CHANNELS; i++)
tasklet_kill(&jzdma->chan[i].vchan.task);
dma_async_device_unregister(&jzdma->dma_device);
return 0;
}
static const struct of_device_id jz4780_dma_dt_match[] = {
{ .compatible = "ingenic,jz4780-dma", .data = NULL },
{},
};
MODULE_DEVICE_TABLE(of, jz4780_dma_dt_match);
static struct platform_driver jz4780_dma_driver = {
.probe = jz4780_dma_probe,
.remove = jz4780_dma_remove,
.driver = {
.name = "jz4780-dma",
.of_match_table = of_match_ptr(jz4780_dma_dt_match),
},
};
static int __init jz4780_dma_init(void)
{
return platform_driver_register(&jz4780_dma_driver);
}
subsys_initcall(jz4780_dma_init);
static void __exit jz4780_dma_exit(void)
{
platform_driver_unregister(&jz4780_dma_driver);
}
module_exit(jz4780_dma_exit);
MODULE_AUTHOR("Alex Smith <alex@alex-smith.me.uk>");
MODULE_DESCRIPTION("Ingenic JZ4780 DMA controller driver");
MODULE_LICENSE("GPL");