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dmaengine: mediatek: Add MediaTek Command-Queue DMA controller for MT6765 SoC 

MediaTek Command-Queue DMA controller (CQDMA) on MT6765 SoC is dedicated
to memory-to-memory transfer through queue based descriptor management.

There are only 3 physical channels inside CQDMA, while the driver is
extended to support 32 virtual channels for multiple dma users to issue
dma requests onto the CQDMA simultaneously.

Signed-off-by: Shun-Chih Yu <shun-chih.yu@mediatek.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Shun-Chih Yu 2018-10-18 15:49:11 +08:00 committed by Vinod Koul
parent 651022382c
commit b1f01e48df
3 changed files with 965 additions and 0 deletions
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13
drivers/dma/mediatek/Kconfig
View File

@ -11,3 +11,16 @@ config MTK_HSDMA
This controller provides the channels which is dedicated to This controller provides the channels which is dedicated to
memory-to-memory transfer to offload from CPU through ring- memory-to-memory transfer to offload from CPU through ring-
based descriptor management. based descriptor management.
config MTK_CQDMA
tristate "MediaTek Command-Queue DMA controller support"
depends on ARCH_MEDIATEK || COMPILE_TEST
select DMA_ENGINE
select DMA_VIRTUAL_CHANNELS
select ASYNC_TX_ENABLE_CHANNEL_SWITCH
help
Enable support for Command-Queue DMA controller on MediaTek
SoCs.
This controller provides the channels which is dedicated to
memory-to-memory transfer to offload from CPU.

1
drivers/dma/mediatek/Makefile
View File

@ -1 +1,2 @@
obj-$(CONFIG_MTK_HSDMA) += mtk-hsdma.o obj-$(CONFIG_MTK_HSDMA) += mtk-hsdma.o
obj-$(CONFIG_MTK_CQDMA) += mtk-cqdma.o

951
drivers/dma/mediatek/mtk-cqdma.c Normal file
View File

@ -0,0 +1,951 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018-2019 MediaTek Inc.
/*
* Driver for MediaTek Command-Queue DMA Controller
*
* Author: Shun-Chih Yu <shun-chih.yu@mediatek.com>
*
*/
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/iopoll.h>
#include <linux/interrupt.h>
#include <linux/list.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/refcount.h>
#include <linux/slab.h>
#include "../virt-dma.h"
#define MTK_CQDMA_USEC_POLL 10
#define MTK_CQDMA_TIMEOUT_POLL 1000
#define MTK_CQDMA_DMA_BUSWIDTHS BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
#define MTK_CQDMA_ALIGN_SIZE 1
/* The default number of virtual channel */
#define MTK_CQDMA_NR_VCHANS 32
/* The default number of physical channel */
#define MTK_CQDMA_NR_PCHANS 3
/* Registers for underlying dma manipulation */
#define MTK_CQDMA_INT_FLAG 0x0
#define MTK_CQDMA_INT_EN 0x4
#define MTK_CQDMA_EN 0x8
#define MTK_CQDMA_RESET 0xc
#define MTK_CQDMA_FLUSH 0x14
#define MTK_CQDMA_SRC 0x1c
#define MTK_CQDMA_DST 0x20
#define MTK_CQDMA_LEN1 0x24
#define MTK_CQDMA_LEN2 0x28
#define MTK_CQDMA_SRC2 0x60
#define MTK_CQDMA_DST2 0x64
/* Registers setting */
#define MTK_CQDMA_EN_BIT BIT(0)
#define MTK_CQDMA_INT_FLAG_BIT BIT(0)
#define MTK_CQDMA_INT_EN_BIT BIT(0)
#define MTK_CQDMA_FLUSH_BIT BIT(0)
#define MTK_CQDMA_WARM_RST_BIT BIT(0)
#define MTK_CQDMA_HARD_RST_BIT BIT(1)
#define MTK_CQDMA_MAX_LEN GENMASK(27, 0)
#define MTK_CQDMA_ADDR_LIMIT GENMASK(31, 0)
#define MTK_CQDMA_ADDR2_SHFIT (32)
/**
* struct mtk_cqdma_vdesc - The struct holding info describing virtual
* descriptor (CVD)
* @vd: An instance for struct virt_dma_desc
* @len: The total data size device wants to move
* @residue: The remaining data size device will move
* @dest: The destination address device wants to move to
* @src: The source address device wants to move from
* @ch: The pointer to the corresponding dma channel
* @node: The lise_head struct to build link-list for VDs
* @parent: The pointer to the parent CVD
*/
struct mtk_cqdma_vdesc {
struct virt_dma_desc vd;
size_t len;
size_t residue;
dma_addr_t dest;
dma_addr_t src;
struct dma_chan *ch;
struct list_head node;
struct mtk_cqdma_vdesc *parent;
};
/**
* struct mtk_cqdma_pchan - The struct holding info describing physical
* channel (PC)
* @queue: Queue for the PDs issued to this PC
* @base: The mapped register I/O base of this PC
* @irq: The IRQ that this PC are using
* @refcnt: Track how many VCs are using this PC
* @tasklet: Tasklet for this PC
* @lock: Lock protect agaisting multiple VCs access PC
*/
struct mtk_cqdma_pchan {
struct list_head queue;
void __iomem *base;
u32 irq;
refcount_t refcnt;
struct tasklet_struct tasklet;
/* lock to protect PC */
spinlock_t lock;
};
/**
* struct mtk_cqdma_vchan - The struct holding info describing virtual
* channel (VC)
* @vc: An instance for struct virt_dma_chan
* @pc: The pointer to the underlying PC
* @issue_completion: The wait for all issued descriptors completited
* @issue_synchronize: Bool indicating channel synchronization starts
*/
struct mtk_cqdma_vchan {
struct virt_dma_chan vc;
struct mtk_cqdma_pchan *pc;
struct completion issue_completion;
bool issue_synchronize;
};
/**
* struct mtk_cqdma_device - The struct holding info describing CQDMA
* device
* @ddev: An instance for struct dma_device
* @clk: The clock that device internal is using
* @dma_requests: The number of VCs the device supports to
* @dma_channels: The number of PCs the device supports to
* @vc: The pointer to all available VCs
* @pc: The pointer to all the underlying PCs
*/
struct mtk_cqdma_device {
struct dma_device ddev;
struct clk *clk;
u32 dma_requests;
u32 dma_channels;
struct mtk_cqdma_vchan *vc;
struct mtk_cqdma_pchan **pc;
};
static struct mtk_cqdma_device *to_cqdma_dev(struct dma_chan *chan)
{
return container_of(chan->device, struct mtk_cqdma_device, ddev);
}
static struct mtk_cqdma_vchan *to_cqdma_vchan(struct dma_chan *chan)
{
return container_of(chan, struct mtk_cqdma_vchan, vc.chan);
}
static struct mtk_cqdma_vdesc *to_cqdma_vdesc(struct virt_dma_desc *vd)
{
return container_of(vd, struct mtk_cqdma_vdesc, vd);
}
static struct device *cqdma2dev(struct mtk_cqdma_device *cqdma)
{
return cqdma->ddev.dev;
}
static u32 mtk_dma_read(struct mtk_cqdma_pchan *pc, u32 reg)
{
return readl(pc->base + reg);
}
static void mtk_dma_write(struct mtk_cqdma_pchan *pc, u32 reg, u32 val)
{
writel_relaxed(val, pc->base + reg);
}
static void mtk_dma_rmw(struct mtk_cqdma_pchan *pc, u32 reg,
u32 mask, u32 set)
{
u32 val;
val = mtk_dma_read(pc, reg);
val &= ~mask;
val |= set;
mtk_dma_write(pc, reg, val);
}
static void mtk_dma_set(struct mtk_cqdma_pchan *pc, u32 reg, u32 val)
{
mtk_dma_rmw(pc, reg, 0, val);
}
static void mtk_dma_clr(struct mtk_cqdma_pchan *pc, u32 reg, u32 val)
{
mtk_dma_rmw(pc, reg, val, 0);
}
static void mtk_cqdma_vdesc_free(struct virt_dma_desc *vd)
{
kfree(to_cqdma_vdesc(vd));
}
static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc, bool atomic)
{
u32 status = 0;
if (!atomic)
return readl_poll_timeout(pc->base + MTK_CQDMA_EN,
status,
!(status & MTK_CQDMA_EN_BIT),
MTK_CQDMA_USEC_POLL,
MTK_CQDMA_TIMEOUT_POLL);
return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN,
status,
!(status & MTK_CQDMA_EN_BIT),
MTK_CQDMA_USEC_POLL,
MTK_CQDMA_TIMEOUT_POLL);
}
static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc)
{
mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT);
mtk_dma_clr(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT);
return mtk_cqdma_poll_engine_done(pc, false);
}
static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc,
struct mtk_cqdma_vdesc *cvd)
{
/* wait for the previous transaction done */
if (mtk_cqdma_poll_engine_done(pc, true) < 0)
dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma wait transaction timeout\n");
/* warm reset the dma engine for the new transaction */
mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_WARM_RST_BIT);
if (mtk_cqdma_poll_engine_done(pc, true) < 0)
dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma warm reset timeout\n");
/* setup the source */
mtk_dma_set(pc, MTK_CQDMA_SRC, cvd->src & MTK_CQDMA_ADDR_LIMIT);
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
mtk_dma_set(pc, MTK_CQDMA_SRC2, cvd->src >> MTK_CQDMA_ADDR2_SHFIT);
#else
mtk_dma_set(pc, MTK_CQDMA_SRC2, 0);
#endif
/* setup the destination */
mtk_dma_set(pc, MTK_CQDMA_DST, cvd->dest & MTK_CQDMA_ADDR_LIMIT);
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
mtk_dma_set(pc, MTK_CQDMA_DST2, cvd->dest >> MTK_CQDMA_ADDR2_SHFIT);
#else
mtk_dma_set(pc, MTK_CQDMA_SRC2, 0);
#endif
/* setup the length */
mtk_dma_set(pc, MTK_CQDMA_LEN1, cvd->len);
/* start dma engine */
mtk_dma_set(pc, MTK_CQDMA_EN, MTK_CQDMA_EN_BIT);
}
static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc)
{
struct virt_dma_desc *vd, *vd2;
struct mtk_cqdma_pchan *pc = cvc->pc;
struct mtk_cqdma_vdesc *cvd;
bool trigger_engine = false;
lockdep_assert_held(&cvc->vc.lock);
lockdep_assert_held(&pc->lock);
list_for_each_entry_safe(vd, vd2, &cvc->vc.desc_issued, node) {
/* need to trigger dma engine if PC's queue is empty */
if (list_empty(&pc->queue))
trigger_engine = true;
cvd = to_cqdma_vdesc(vd);
/* add VD into PC's queue */
list_add_tail(&cvd->node, &pc->queue);
/* start the dma engine */
if (trigger_engine)
mtk_cqdma_start(pc, cvd);
/* remove VD from list desc_issued */
list_del(&vd->node);
}
}
/*
* return true if this VC is active,
* meaning that there are VDs under processing by the PC
*/
static bool mtk_cqdma_is_vchan_active(struct mtk_cqdma_vchan *cvc)
{
struct mtk_cqdma_vdesc *cvd;
list_for_each_entry(cvd, &cvc->pc->queue, node)
if (cvc == to_cqdma_vchan(cvd->ch))
return true;
return false;
}
/*
* return the pointer of the CVD that is just consumed by the PC
*/
static struct mtk_cqdma_vdesc
*mtk_cqdma_consume_work_queue(struct mtk_cqdma_pchan *pc)
{
struct mtk_cqdma_vchan *cvc;
struct mtk_cqdma_vdesc *cvd, *ret = NULL;
/* consume a CVD from PC's queue */
cvd = list_first_entry_or_null(&pc->queue,
struct mtk_cqdma_vdesc, node);
if (unlikely(!cvd || !cvd->parent))
return NULL;
cvc = to_cqdma_vchan(cvd->ch);
ret = cvd;
/* update residue of the parent CVD */
cvd->parent->residue -= cvd->len;
/* delete CVD from PC's queue */
list_del(&cvd->node);
spin_lock(&cvc->vc.lock);
/* check whether all the child CVDs completed */
if (!cvd->parent->residue) {
/* add the parent VD into list desc_completed */
vchan_cookie_complete(&cvd->parent->vd);
/* setup completion if this VC is under synchronization */
if (cvc->issue_synchronize && !mtk_cqdma_is_vchan_active(cvc)) {
complete(&cvc->issue_completion);
cvc->issue_synchronize = false;
}
}
spin_unlock(&cvc->vc.lock);
/* start transaction for next CVD in the queue */
cvd = list_first_entry_or_null(&pc->queue,
struct mtk_cqdma_vdesc, node);
if (cvd)
mtk_cqdma_start(pc, cvd);
return ret;
}
static void mtk_cqdma_tasklet_cb(unsigned long data)
{
struct mtk_cqdma_pchan *pc = (struct mtk_cqdma_pchan *)data;
struct mtk_cqdma_vdesc *cvd = NULL;
unsigned long flags;
spin_lock_irqsave(&pc->lock, flags);
/* consume the queue */
cvd = mtk_cqdma_consume_work_queue(pc);
spin_unlock_irqrestore(&pc->lock, flags);
/* submit the next CVD */
if (cvd) {
dma_run_dependencies(&cvd->vd.tx);
/*
* free child CVD after completion.
* the parent CVD would be freeed with desc_free by user.
*/
if (cvd->parent != cvd)
kfree(cvd);
}
/* re-enable interrupt before leaving tasklet */
enable_irq(pc->irq);
}
static irqreturn_t mtk_cqdma_irq(int irq, void *devid)
{
struct mtk_cqdma_device *cqdma = devid;
irqreturn_t ret = IRQ_NONE;
bool schedule_tasklet = false;
u32 i;
/* clear interrupt flags for each PC */
for (i = 0; i < cqdma->dma_channels; ++i, schedule_tasklet = false) {
spin_lock(&cqdma->pc[i]->lock);
if (mtk_dma_read(cqdma->pc[i],
MTK_CQDMA_INT_FLAG) & MTK_CQDMA_INT_FLAG_BIT) {
/* clear interrupt */
mtk_dma_clr(cqdma->pc[i], MTK_CQDMA_INT_FLAG,
MTK_CQDMA_INT_FLAG_BIT);
schedule_tasklet = true;
ret = IRQ_HANDLED;
}
spin_unlock(&cqdma->pc[i]->lock);
if (schedule_tasklet) {
/* disable interrupt */
disable_irq_nosync(cqdma->pc[i]->irq);
/* schedule the tasklet to handle the transactions */
tasklet_schedule(&cqdma->pc[i]->tasklet);
}
}
return ret;
}
static struct virt_dma_desc *mtk_cqdma_find_active_desc(struct dma_chan *c,
dma_cookie_t cookie)
{
struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);
struct virt_dma_desc *vd;
unsigned long flags;
spin_lock_irqsave(&cvc->pc->lock, flags);
list_for_each_entry(vd, &cvc->pc->queue, node)
if (vd->tx.cookie == cookie) {
spin_unlock_irqrestore(&cvc->pc->lock, flags);
return vd;
}
spin_unlock_irqrestore(&cvc->pc->lock, flags);
list_for_each_entry(vd, &cvc->vc.desc_issued, node)
if (vd->tx.cookie == cookie)
return vd;
return NULL;
}
static enum dma_status mtk_cqdma_tx_status(struct dma_chan *c,
dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);
struct mtk_cqdma_vdesc *cvd;
struct virt_dma_desc *vd;
enum dma_status ret;
unsigned long flags;
size_t bytes = 0;
ret = dma_cookie_status(c, cookie, txstate);
if (ret == DMA_COMPLETE || !txstate)
return ret;
spin_lock_irqsave(&cvc->vc.lock, flags);
vd = mtk_cqdma_find_active_desc(c, cookie);
spin_unlock_irqrestore(&cvc->vc.lock, flags);
if (vd) {
cvd = to_cqdma_vdesc(vd);
bytes = cvd->residue;
}
dma_set_residue(txstate, bytes);
return ret;
}
static void mtk_cqdma_issue_pending(struct dma_chan *c)
{
struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);
unsigned long pc_flags;
unsigned long vc_flags;
/* acquire PC's lock before VS's lock for lock dependency in tasklet */
spin_lock_irqsave(&cvc->pc->lock, pc_flags);
spin_lock_irqsave(&cvc->vc.lock, vc_flags);
if (vchan_issue_pending(&cvc->vc))
mtk_cqdma_issue_vchan_pending(cvc);
spin_unlock_irqrestore(&cvc->vc.lock, vc_flags);
spin_unlock_irqrestore(&cvc->pc->lock, pc_flags);
}
static struct dma_async_tx_descriptor *
mtk_cqdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest,
dma_addr_t src, size_t len, unsigned long flags)
{
struct mtk_cqdma_vdesc **cvd;
struct dma_async_tx_descriptor *tx = NULL, *prev_tx = NULL;
size_t i, tlen, nr_vd;
/*
* In the case that trsanction length is larger than the
* DMA engine supports, a single memcpy transaction needs
* to be separated into several DMA transactions.
* Each DMA transaction would be described by a CVD,
* and the first one is referred as the parent CVD,
* while the others are child CVDs.
* The parent CVD's tx descriptor is the only tx descriptor
* returned to the DMA user, and it should not be completed
* until all the child CVDs completed.
*/
nr_vd = DIV_ROUND_UP(len, MTK_CQDMA_MAX_LEN);
cvd = kcalloc(nr_vd, sizeof(*cvd), GFP_NOWAIT);
if (!cvd)
return NULL;
for (i = 0; i < nr_vd; ++i) {
cvd[i] = kzalloc(sizeof(*cvd[i]), GFP_NOWAIT);
if (!cvd[i]) {
for (; i > 0; --i)
kfree(cvd[i - 1]);
return NULL;
}
/* setup dma channel */
cvd[i]->ch = c;
/* setup sourece, destination, and length */
tlen = (len > MTK_CQDMA_MAX_LEN) ? MTK_CQDMA_MAX_LEN : len;
cvd[i]->len = tlen;
cvd[i]->src = src;
cvd[i]->dest = dest;
/* setup tx descriptor */
tx = vchan_tx_prep(to_virt_chan(c), &cvd[i]->vd, flags);
tx->next = NULL;
if (!i) {
cvd[0]->residue = len;
} else {
prev_tx->next = tx;
cvd[i]->residue = tlen;
}
cvd[i]->parent = cvd[0];
/* update the src, dest, len, prev_tx for the next CVD */
src += tlen;
dest += tlen;
len -= tlen;
prev_tx = tx;
}
return &cvd[0]->vd.tx;
}
static void mtk_cqdma_free_inactive_desc(struct dma_chan *c)
{
struct virt_dma_chan *vc = to_virt_chan(c);
unsigned long flags;
LIST_HEAD(head);
/*
* set desc_allocated, desc_submitted,
* and desc_issued as the candicates to be freed
*/
spin_lock_irqsave(&vc->lock, flags);
list_splice_tail_init(&vc->desc_allocated, &head);
list_splice_tail_init(&vc->desc_submitted, &head);
list_splice_tail_init(&vc->desc_issued, &head);
spin_unlock_irqrestore(&vc->lock, flags);
/* free descriptor lists */
vchan_dma_desc_free_list(vc, &head);
}
static void mtk_cqdma_free_active_desc(struct dma_chan *c)
{
struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);
bool sync_needed = false;
unsigned long pc_flags;
unsigned long vc_flags;
/* acquire PC's lock first due to lock dependency in dma ISR */
spin_lock_irqsave(&cvc->pc->lock, pc_flags);
spin_lock_irqsave(&cvc->vc.lock, vc_flags);
/* synchronization is required if this VC is active */
if (mtk_cqdma_is_vchan_active(cvc)) {
cvc->issue_synchronize = true;
sync_needed = true;
}
spin_unlock_irqrestore(&cvc->vc.lock, vc_flags);
spin_unlock_irqrestore(&cvc->pc->lock, pc_flags);
/* waiting for the completion of this VC */
if (sync_needed)
wait_for_completion(&cvc->issue_completion);
/* free all descriptors in list desc_completed */
vchan_synchronize(&cvc->vc);
WARN_ONCE(!list_empty(&cvc->vc.desc_completed),
"Desc pending still in list desc_completed\n");
}
static int mtk_cqdma_terminate_all(struct dma_chan *c)
{
/* free descriptors not processed yet by hardware */
mtk_cqdma_free_inactive_desc(c);
/* free descriptors being processed by hardware */
mtk_cqdma_free_active_desc(c);
return 0;
}
static int mtk_cqdma_alloc_chan_resources(struct dma_chan *c)
{
struct mtk_cqdma_device *cqdma = to_cqdma_dev(c);
struct mtk_cqdma_vchan *vc = to_cqdma_vchan(c);
struct mtk_cqdma_pchan *pc = NULL;
u32 i, min_refcnt = U32_MAX, refcnt;
unsigned long flags;
/* allocate PC with the minimun refcount */
for (i = 0; i < cqdma->dma_channels; ++i) {
refcnt = refcount_read(&cqdma->pc[i]->refcnt);
if (refcnt < min_refcnt) {
pc = cqdma->pc[i];
min_refcnt = refcnt;
}
}
if (!pc)
return -ENOSPC;
spin_lock_irqsave(&pc->lock, flags);
if (!refcount_read(&pc->refcnt)) {
/* allocate PC when the refcount is zero */
mtk_cqdma_hard_reset(pc);
/* enable interrupt for this PC */
mtk_dma_set(pc, MTK_CQDMA_INT_EN, MTK_CQDMA_INT_EN_BIT);
/*
* refcount_inc would complain increment on 0; use-after-free.
* Thus, we need to explicitly set it as 1 initially.
*/
refcount_set(&pc->refcnt, 1);
} else {
refcount_inc(&pc->refcnt);
}
spin_unlock_irqrestore(&pc->lock, flags);
vc->pc = pc;
return 0;
}
static void mtk_cqdma_free_chan_resources(struct dma_chan *c)
{
struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c);
unsigned long flags;
/* free all descriptors in all lists on the VC */
mtk_cqdma_terminate_all(c);
spin_lock_irqsave(&cvc->pc->lock, flags);
/* PC is not freed until there is no VC mapped to it */
if (refcount_dec_and_test(&cvc->pc->refcnt)) {
/* start the flush operation and stop the engine */
mtk_dma_set(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT);
/* wait for the completion of flush operation */
if (mtk_cqdma_poll_engine_done(cvc->pc, false) < 0)
dev_err(cqdma2dev(to_cqdma_dev(c)), "cqdma flush timeout\n");
/* clear the flush bit and interrupt flag */
mtk_dma_clr(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT);
mtk_dma_clr(cvc->pc, MTK_CQDMA_INT_FLAG,
MTK_CQDMA_INT_FLAG_BIT);
/* disable interrupt for this PC */
mtk_dma_clr(cvc->pc, MTK_CQDMA_INT_EN, MTK_CQDMA_INT_EN_BIT);
}
spin_unlock_irqrestore(&cvc->pc->lock, flags);
}
static int mtk_cqdma_hw_init(struct mtk_cqdma_device *cqdma)
{
unsigned long flags;
int err;
u32 i;
pm_runtime_enable(cqdma2dev(cqdma));
pm_runtime_get_sync(cqdma2dev(cqdma));
err = clk_prepare_enable(cqdma->clk);
if (err) {
pm_runtime_put_sync(cqdma2dev(cqdma));
pm_runtime_disable(cqdma2dev(cqdma));
return err;
}
/* reset all PCs */
for (i = 0; i < cqdma->dma_channels; ++i) {
spin_lock_irqsave(&cqdma->pc[i]->lock, flags);
if (mtk_cqdma_hard_reset(cqdma->pc[i]) < 0) {
dev_err(cqdma2dev(cqdma), "cqdma hard reset timeout\n");
spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);
clk_disable_unprepare(cqdma->clk);
pm_runtime_put_sync(cqdma2dev(cqdma));
pm_runtime_disable(cqdma2dev(cqdma));
return -EINVAL;
}
spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);
}
return 0;
}
static void mtk_cqdma_hw_deinit(struct mtk_cqdma_device *cqdma)
{
unsigned long flags;
u32 i;
/* reset all PCs */
for (i = 0; i < cqdma->dma_channels; ++i) {
spin_lock_irqsave(&cqdma->pc[i]->lock, flags);
if (mtk_cqdma_hard_reset(cqdma->pc[i]) < 0)
dev_err(cqdma2dev(cqdma), "cqdma hard reset timeout\n");
spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);
}
clk_disable_unprepare(cqdma->clk);
pm_runtime_put_sync(cqdma2dev(cqdma));
pm_runtime_disable(cqdma2dev(cqdma));
}
static const struct of_device_id mtk_cqdma_match[] = {
{ .compatible = "mediatek,mt6765-cqdma" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mtk_cqdma_match);
static int mtk_cqdma_probe(struct platform_device *pdev)
{
struct mtk_cqdma_device *cqdma;
struct mtk_cqdma_vchan *vc;
struct dma_device *dd;
struct resource *res;
int err;
u32 i;
cqdma = devm_kzalloc(&pdev->dev, sizeof(*cqdma), GFP_KERNEL);
if (!cqdma)
return -ENOMEM;
dd = &cqdma->ddev;
cqdma->clk = devm_clk_get(&pdev->dev, "cqdma");
if (IS_ERR(cqdma->clk)) {
dev_err(&pdev->dev, "No clock for %s\n",
dev_name(&pdev->dev));
return PTR_ERR(cqdma->clk);
}
dma_cap_set(DMA_MEMCPY, dd->cap_mask);
dd->copy_align = MTK_CQDMA_ALIGN_SIZE;
dd->device_alloc_chan_resources = mtk_cqdma_alloc_chan_resources;
dd->device_free_chan_resources = mtk_cqdma_free_chan_resources;
dd->device_tx_status = mtk_cqdma_tx_status;
dd->device_issue_pending = mtk_cqdma_issue_pending;
dd->device_prep_dma_memcpy = mtk_cqdma_prep_dma_memcpy;
dd->device_terminate_all = mtk_cqdma_terminate_all;
dd->src_addr_widths = MTK_CQDMA_DMA_BUSWIDTHS;
dd->dst_addr_widths = MTK_CQDMA_DMA_BUSWIDTHS;
dd->directions = BIT(DMA_MEM_TO_MEM);
dd->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
dd->dev = &pdev->dev;
INIT_LIST_HEAD(&dd->channels);
if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,
"dma-requests",
&cqdma->dma_requests)) {
dev_info(&pdev->dev,
"Using %u as missing dma-requests property\n",
MTK_CQDMA_NR_VCHANS);
cqdma->dma_requests = MTK_CQDMA_NR_VCHANS;
}
if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,
"dma-channels",
&cqdma->dma_channels)) {
dev_info(&pdev->dev,
"Using %u as missing dma-channels property\n",
MTK_CQDMA_NR_PCHANS);
cqdma->dma_channels = MTK_CQDMA_NR_PCHANS;
}
cqdma->pc = devm_kcalloc(&pdev->dev, cqdma->dma_channels,
sizeof(*cqdma->pc), GFP_KERNEL);
if (!cqdma->pc)
return -ENOMEM;
/* initialization for PCs */
for (i = 0; i < cqdma->dma_channels; ++i) {
cqdma->pc[i] = devm_kcalloc(&pdev->dev, 1,
sizeof(**cqdma->pc), GFP_KERNEL);
if (!cqdma->pc[i])
return -ENOMEM;
INIT_LIST_HEAD(&cqdma->pc[i]->queue);
spin_lock_init(&cqdma->pc[i]->lock);
refcount_set(&cqdma->pc[i]->refcnt, 0);
res = platform_get_resource(pdev, IORESOURCE_MEM, i);
if (!res) {
dev_err(&pdev->dev, "No mem resource for %s\n",
dev_name(&pdev->dev));
return -EINVAL;
}
cqdma->pc[i]->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(cqdma->pc[i]->base))
return PTR_ERR(cqdma->pc[i]->base);
/* allocate IRQ resource */
res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
if (!res) {
dev_err(&pdev->dev, "No irq resource for %s\n",
dev_name(&pdev->dev));
return -EINVAL;
}
cqdma->pc[i]->irq = res->start;
err = devm_request_irq(&pdev->dev, cqdma->pc[i]->irq,
mtk_cqdma_irq, 0, dev_name(&pdev->dev),
cqdma);
if (err) {
dev_err(&pdev->dev,
"request_irq failed with err %d\n", err);
return -EINVAL;
}
}
/* allocate resource for VCs */
cqdma->vc = devm_kcalloc(&pdev->dev, cqdma->dma_requests,
sizeof(*cqdma->vc), GFP_KERNEL);
if (!cqdma->vc)
return -ENOMEM;
for (i = 0; i < cqdma->dma_requests; i++) {
vc = &cqdma->vc[i];
vc->vc.desc_free = mtk_cqdma_vdesc_free;
vchan_init(&vc->vc, dd);
init_completion(&vc->issue_completion);
}
err = dma_async_device_register(dd);
if (err)
return err;
err = of_dma_controller_register(pdev->dev.of_node,
of_dma_xlate_by_chan_id, cqdma);
if (err) {
dev_err(&pdev->dev,
"MediaTek CQDMA OF registration failed %d\n", err);
goto err_unregister;
}
err = mtk_cqdma_hw_init(cqdma);
if (err) {
dev_err(&pdev->dev,
"MediaTek CQDMA HW initialization failed %d\n", err);
goto err_unregister;
}
platform_set_drvdata(pdev, cqdma);
/* initialize tasklet for each PC */
for (i = 0; i < cqdma->dma_channels; ++i)
tasklet_init(&cqdma->pc[i]->tasklet, mtk_cqdma_tasklet_cb,
(unsigned long)cqdma->pc[i]);
dev_info(&pdev->dev, "MediaTek CQDMA driver registered\n");
return 0;
err_unregister:
dma_async_device_unregister(dd);
return err;
}
static int mtk_cqdma_remove(struct platform_device *pdev)
{
struct mtk_cqdma_device *cqdma = platform_get_drvdata(pdev);
struct mtk_cqdma_vchan *vc;
unsigned long flags;
int i;
/* kill VC task */
for (i = 0; i < cqdma->dma_requests; i++) {
vc = &cqdma->vc[i];
list_del(&vc->vc.chan.device_node);
tasklet_kill(&vc->vc.task);
}
/* disable interrupt */
for (i = 0; i < cqdma->dma_channels; i++) {
spin_lock_irqsave(&cqdma->pc[i]->lock, flags);
mtk_dma_clr(cqdma->pc[i], MTK_CQDMA_INT_EN,
MTK_CQDMA_INT_EN_BIT);
spin_unlock_irqrestore(&cqdma->pc[i]->lock, flags);
/* Waits for any pending IRQ handlers to complete */
synchronize_irq(cqdma->pc[i]->irq);
tasklet_kill(&cqdma->pc[i]->tasklet);
}
/* disable hardware */
mtk_cqdma_hw_deinit(cqdma);
dma_async_device_unregister(&cqdma->ddev);
of_dma_controller_free(pdev->dev.of_node);
return 0;
}
static struct platform_driver mtk_cqdma_driver = {
.probe = mtk_cqdma_probe,
.remove = mtk_cqdma_remove,
.driver = {
.name = KBUILD_MODNAME,
.of_match_table = mtk_cqdma_match,
},
};
module_platform_driver(mtk_cqdma_driver);
MODULE_DESCRIPTION("MediaTek CQDMA Controller Driver");
MODULE_AUTHOR("Shun-Chih Yu <shun-chih.yu@mediatek.com>");
MODULE_LICENSE("GPL v2");