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-rw-r--r--target/linux/ramips/patches-4.9/0047-DMA-ralink-add-rt2880-dma-engine.patch1757
1 files changed, 1757 insertions, 0 deletions
diff --git a/target/linux/ramips/patches-4.9/0047-DMA-ralink-add-rt2880-dma-engine.patch b/target/linux/ramips/patches-4.9/0047-DMA-ralink-add-rt2880-dma-engine.patch
new file mode 100644
index 0000000000..9b45cf4573
--- /dev/null
+++ b/target/linux/ramips/patches-4.9/0047-DMA-ralink-add-rt2880-dma-engine.patch
@@ -0,0 +1,1757 @@
+From f1c4d9e622c800e1f38b3818f933ec7597d1ccfb Mon Sep 17 00:00:00 2001
+From: John Crispin <blogic@openwrt.org>
+Date: Sun, 27 Jul 2014 09:29:51 +0100
+Subject: [PATCH 47/53] DMA: ralink: add rt2880 dma engine
+
+Signed-off-by: John Crispin <blogic@openwrt.org>
+---
+ drivers/dma/Kconfig | 6 +
+ drivers/dma/Makefile | 1 +
+ drivers/dma/ralink-gdma.c | 577 +++++++++++++++++++++++++++++++++++++++++++++
+ include/linux/dmaengine.h | 1 +
+ 4 files changed, 585 insertions(+)
+ create mode 100644 drivers/dma/ralink-gdma.c
+
+--- a/drivers/dma/Kconfig
++++ b/drivers/dma/Kconfig
+@@ -40,6 +40,18 @@ config ASYNC_TX_ENABLE_CHANNEL_SWITCH
+ config ARCH_HAS_ASYNC_TX_FIND_CHANNEL
+ bool
+
++config DMA_RALINK
++ tristate "RALINK DMA support"
++ depends on RALINK && !SOC_RT288X
++ select DMA_ENGINE
++ select DMA_VIRTUAL_CHANNELS
++
++config MTK_HSDMA
++ tristate "MTK HSDMA support"
++ depends on RALINK && SOC_MT7621
++ select DMA_ENGINE
++ select DMA_VIRTUAL_CHANNELS
++
+ config DMA_ENGINE
+ bool
+
+--- a/drivers/dma/Makefile
++++ b/drivers/dma/Makefile
+@@ -67,6 +67,8 @@ obj-$(CONFIG_TI_DMA_CROSSBAR) += ti-dma-
+ obj-$(CONFIG_TI_EDMA) += edma.o
+ obj-$(CONFIG_XGENE_DMA) += xgene-dma.o
+ obj-$(CONFIG_ZX_DMA) += zx296702_dma.o
++obj-$(CONFIG_DMA_RALINK) += ralink-gdma.o
++obj-$(CONFIG_MTK_HSDMA) += mtk-hsdma.o
+
+ obj-y += qcom/
+ obj-y += xilinx/
+--- /dev/null
++++ b/drivers/dma/ralink-gdma.c
+@@ -0,0 +1,928 @@
++/*
++ * Copyright (C) 2013, Lars-Peter Clausen <lars@metafoo.de>
++ * GDMA4740 DMAC support
++ *
++ * 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/dmaengine.h>
++#include <linux/dma-mapping.h>
++#include <linux/err.h>
++#include <linux/init.h>
++#include <linux/list.h>
++#include <linux/module.h>
++#include <linux/platform_device.h>
++#include <linux/slab.h>
++#include <linux/spinlock.h>
++#include <linux/irq.h>
++#include <linux/of_dma.h>
++#include <linux/reset.h>
++#include <linux/of_device.h>
++
++#include "virt-dma.h"
++
++#define GDMA_REG_SRC_ADDR(x) (0x00 + (x) * 0x10)
++#define GDMA_REG_DST_ADDR(x) (0x04 + (x) * 0x10)
++
++#define GDMA_REG_CTRL0(x) (0x08 + (x) * 0x10)
++#define GDMA_REG_CTRL0_TX_MASK 0xffff
++#define GDMA_REG_CTRL0_TX_SHIFT 16
++#define GDMA_REG_CTRL0_CURR_MASK 0xff
++#define GDMA_REG_CTRL0_CURR_SHIFT 8
++#define GDMA_REG_CTRL0_SRC_ADDR_FIXED BIT(7)
++#define GDMA_REG_CTRL0_DST_ADDR_FIXED BIT(6)
++#define GDMA_REG_CTRL0_BURST_MASK 0x7
++#define GDMA_REG_CTRL0_BURST_SHIFT 3
++#define GDMA_REG_CTRL0_DONE_INT BIT(2)
++#define GDMA_REG_CTRL0_ENABLE BIT(1)
++#define GDMA_REG_CTRL0_SW_MODE BIT(0)
++
++#define GDMA_REG_CTRL1(x) (0x0c + (x) * 0x10)
++#define GDMA_REG_CTRL1_SEG_MASK 0xf
++#define GDMA_REG_CTRL1_SEG_SHIFT 22
++#define GDMA_REG_CTRL1_REQ_MASK 0x3f
++#define GDMA_REG_CTRL1_SRC_REQ_SHIFT 16
++#define GDMA_REG_CTRL1_DST_REQ_SHIFT 8
++#define GDMA_REG_CTRL1_CONTINOUS BIT(14)
++#define GDMA_REG_CTRL1_NEXT_MASK 0x1f
++#define GDMA_REG_CTRL1_NEXT_SHIFT 3
++#define GDMA_REG_CTRL1_COHERENT BIT(2)
++#define GDMA_REG_CTRL1_FAIL BIT(1)
++#define GDMA_REG_CTRL1_MASK BIT(0)
++
++#define GDMA_REG_UNMASK_INT 0x200
++#define GDMA_REG_DONE_INT 0x204
++
++#define GDMA_REG_GCT 0x220
++#define GDMA_REG_GCT_CHAN_MASK 0x3
++#define GDMA_REG_GCT_CHAN_SHIFT 3
++#define GDMA_REG_GCT_VER_MASK 0x3
++#define GDMA_REG_GCT_VER_SHIFT 1
++#define GDMA_REG_GCT_ARBIT_RR BIT(0)
++
++#define GDMA_REG_REQSTS 0x2a0
++#define GDMA_REG_ACKSTS 0x2a4
++#define GDMA_REG_FINSTS 0x2a8
++
++/* for RT305X gdma registers */
++#define GDMA_RT305X_CTRL0_REQ_MASK 0xf
++#define GDMA_RT305X_CTRL0_SRC_REQ_SHIFT 12
++#define GDMA_RT305X_CTRL0_DST_REQ_SHIFT 8
++
++#define GDMA_RT305X_CTRL1_FAIL BIT(4)
++#define GDMA_RT305X_CTRL1_NEXT_MASK 0x7
++#define GDMA_RT305X_CTRL1_NEXT_SHIFT 1
++
++#define GDMA_RT305X_STATUS_INT 0x80
++#define GDMA_RT305X_STATUS_SIGNAL 0x84
++#define GDMA_RT305X_GCT 0x88
++
++/* for MT7621 gdma registers */
++#define GDMA_REG_PERF_START(x) (0x230 + (x) * 0x8)
++#define GDMA_REG_PERF_END(x) (0x234 + (x) * 0x8)
++
++enum gdma_dma_transfer_size {
++ GDMA_TRANSFER_SIZE_4BYTE = 0,
++ GDMA_TRANSFER_SIZE_8BYTE = 1,
++ GDMA_TRANSFER_SIZE_16BYTE = 2,
++ GDMA_TRANSFER_SIZE_32BYTE = 3,
++ GDMA_TRANSFER_SIZE_64BYTE = 4,
++};
++
++struct gdma_dma_sg {
++ dma_addr_t src_addr;
++ dma_addr_t dst_addr;
++ u32 len;
++};
++
++struct gdma_dma_desc {
++ struct virt_dma_desc vdesc;
++
++ enum dma_transfer_direction direction;
++ bool cyclic;
++
++ u32 residue;
++ unsigned int num_sgs;
++ struct gdma_dma_sg sg[];
++};
++
++struct gdma_dmaengine_chan {
++ struct virt_dma_chan vchan;
++ unsigned int id;
++ unsigned int slave_id;
++
++ dma_addr_t fifo_addr;
++ enum gdma_dma_transfer_size burst_size;
++
++ struct gdma_dma_desc *desc;
++ unsigned int next_sg;
++};
++
++struct gdma_dma_dev {
++ struct dma_device ddev;
++ struct device_dma_parameters dma_parms;
++ struct gdma_data *data;
++ void __iomem *base;
++ struct tasklet_struct task;
++ volatile unsigned long chan_issued;
++ atomic_t cnt;
++
++ struct gdma_dmaengine_chan chan[];
++};
++
++struct gdma_data
++{
++ int chancnt;
++ u32 done_int_reg;
++ void (*init)(struct gdma_dma_dev *dma_dev);
++ int (*start_transfer)(struct gdma_dmaengine_chan *chan);
++};
++
++static struct gdma_dma_dev *gdma_dma_chan_get_dev(
++ struct gdma_dmaengine_chan *chan)
++{
++ return container_of(chan->vchan.chan.device, struct gdma_dma_dev,
++ ddev);
++}
++
++static struct gdma_dmaengine_chan *to_gdma_dma_chan(struct dma_chan *c)
++{
++ return container_of(c, struct gdma_dmaengine_chan, vchan.chan);
++}
++
++static struct gdma_dma_desc *to_gdma_dma_desc(struct virt_dma_desc *vdesc)
++{
++ return container_of(vdesc, struct gdma_dma_desc, vdesc);
++}
++
++static inline uint32_t gdma_dma_read(struct gdma_dma_dev *dma_dev,
++ unsigned int reg)
++{
++ return readl(dma_dev->base + reg);
++}
++
++static inline void gdma_dma_write(struct gdma_dma_dev *dma_dev,
++ unsigned reg, uint32_t val)
++{
++ writel(val, dma_dev->base + reg);
++}
++
++static struct gdma_dma_desc *gdma_dma_alloc_desc(unsigned int num_sgs)
++{
++ return kzalloc(sizeof(struct gdma_dma_desc) +
++ sizeof(struct gdma_dma_sg) * num_sgs, GFP_ATOMIC);
++}
++
++static enum gdma_dma_transfer_size gdma_dma_maxburst(u32 maxburst)
++{
++ if (maxburst < 2)
++ return GDMA_TRANSFER_SIZE_4BYTE;
++ else if (maxburst < 4)
++ return GDMA_TRANSFER_SIZE_8BYTE;
++ else if (maxburst < 8)
++ return GDMA_TRANSFER_SIZE_16BYTE;
++ else if (maxburst < 16)
++ return GDMA_TRANSFER_SIZE_32BYTE;
++ else
++ return GDMA_TRANSFER_SIZE_64BYTE;
++}
++
++static int gdma_dma_config(struct dma_chan *c,
++ struct dma_slave_config *config)
++{
++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
++
++ if (config->device_fc) {
++ dev_err(dma_dev->ddev.dev, "not support flow controller\n");
++ return -EINVAL;
++ }
++
++ switch (config->direction) {
++ case DMA_MEM_TO_DEV:
++ if (config->dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) {
++ dev_err(dma_dev->ddev.dev, "only support 4 byte buswidth\n");
++ return -EINVAL;
++ }
++ chan->slave_id = config->slave_id;
++ chan->fifo_addr = config->dst_addr;
++ chan->burst_size = gdma_dma_maxburst(config->dst_maxburst);
++ break;
++ case DMA_DEV_TO_MEM:
++ if (config->src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) {
++ dev_err(dma_dev->ddev.dev, "only support 4 byte buswidth\n");
++ return -EINVAL;
++ }
++ chan->slave_id = config->slave_id;
++ chan->fifo_addr = config->src_addr;
++ chan->burst_size = gdma_dma_maxburst(config->src_maxburst);
++ break;
++ default:
++ dev_err(dma_dev->ddev.dev, "direction type %d error\n",
++ config->direction);
++ return -EINVAL;
++ }
++
++ return 0;
++}
++
++static int gdma_dma_terminate_all(struct dma_chan *c)
++{
++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
++ unsigned long flags, timeout;
++ LIST_HEAD(head);
++ int i = 0;
++
++ spin_lock_irqsave(&chan->vchan.lock, flags);
++ chan->desc = NULL;
++ clear_bit(chan->id, &dma_dev->chan_issued);
++ vchan_get_all_descriptors(&chan->vchan, &head);
++ spin_unlock_irqrestore(&chan->vchan.lock, flags);
++
++ vchan_dma_desc_free_list(&chan->vchan, &head);
++
++ /* wait dma transfer complete */
++ timeout = jiffies + msecs_to_jiffies(5000);
++ while (gdma_dma_read(dma_dev, GDMA_REG_CTRL0(chan->id)) &
++ GDMA_REG_CTRL0_ENABLE) {
++ if (time_after_eq(jiffies, timeout)) {
++ dev_err(dma_dev->ddev.dev, "chan %d wait timeout\n",
++ chan->id);
++ /* restore to init value */
++ gdma_dma_write(dma_dev, GDMA_REG_CTRL0(chan->id), 0);
++ break;
++ }
++ cpu_relax();
++ i++;
++ }
++
++ if (i)
++ dev_dbg(dma_dev->ddev.dev, "terminate chan %d loops %d\n",
++ chan->id, i);
++
++ return 0;
++}
++
++static void rt305x_dump_reg(struct gdma_dma_dev *dma_dev, int id)
++{
++ dev_dbg(dma_dev->ddev.dev, "chan %d, src %08x, dst %08x, ctr0 %08x, " \
++ "ctr1 %08x, intr %08x, signal %08x\n", id,
++ gdma_dma_read(dma_dev, GDMA_REG_SRC_ADDR(id)),
++ gdma_dma_read(dma_dev, GDMA_REG_DST_ADDR(id)),
++ gdma_dma_read(dma_dev, GDMA_REG_CTRL0(id)),
++ gdma_dma_read(dma_dev, GDMA_REG_CTRL1(id)),
++ gdma_dma_read(dma_dev, GDMA_RT305X_STATUS_INT),
++ gdma_dma_read(dma_dev, GDMA_RT305X_STATUS_SIGNAL));
++}
++
++static int rt305x_gdma_start_transfer(struct gdma_dmaengine_chan *chan)
++{
++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
++ dma_addr_t src_addr, dst_addr;
++ struct gdma_dma_sg *sg;
++ uint32_t ctrl0, ctrl1;
++
++ /* verify chan is already stopped */
++ ctrl0 = gdma_dma_read(dma_dev, GDMA_REG_CTRL0(chan->id));
++ if (unlikely(ctrl0 & GDMA_REG_CTRL0_ENABLE)) {
++ dev_err(dma_dev->ddev.dev, "chan %d is start(%08x).\n",
++ chan->id, ctrl0);
++ rt305x_dump_reg(dma_dev, chan->id);
++ return -EINVAL;
++ }
++
++ sg = &chan->desc->sg[chan->next_sg];
++ if (chan->desc->direction == DMA_MEM_TO_DEV) {
++ src_addr = sg->src_addr;
++ dst_addr = chan->fifo_addr;
++ ctrl0 = GDMA_REG_CTRL0_DST_ADDR_FIXED | \
++ (8 << GDMA_RT305X_CTRL0_SRC_REQ_SHIFT) | \
++ (chan->slave_id << GDMA_RT305X_CTRL0_DST_REQ_SHIFT);
++ } else if (chan->desc->direction == DMA_DEV_TO_MEM) {
++ src_addr = chan->fifo_addr;
++ dst_addr = sg->dst_addr;
++ ctrl0 = GDMA_REG_CTRL0_SRC_ADDR_FIXED | \
++ (chan->slave_id << GDMA_RT305X_CTRL0_SRC_REQ_SHIFT) | \
++ (8 << GDMA_RT305X_CTRL0_DST_REQ_SHIFT);
++ } else if (chan->desc->direction == DMA_MEM_TO_MEM) {
++ /*
++ * TODO: memcpy function have bugs. sometime it will copy
++ * more 8 bytes data when using dmatest verify.
++ */
++ src_addr = sg->src_addr;
++ dst_addr = sg->dst_addr;
++ ctrl0 = GDMA_REG_CTRL0_SW_MODE | \
++ (8 << GDMA_REG_CTRL1_SRC_REQ_SHIFT) | \
++ (8 << GDMA_REG_CTRL1_DST_REQ_SHIFT);
++ } else {
++ dev_err(dma_dev->ddev.dev, "direction type %d error\n",
++ chan->desc->direction);
++ return -EINVAL;
++ }
++
++ ctrl0 |= (sg->len << GDMA_REG_CTRL0_TX_SHIFT) | \
++ (chan->burst_size << GDMA_REG_CTRL0_BURST_SHIFT) | \
++ GDMA_REG_CTRL0_DONE_INT | GDMA_REG_CTRL0_ENABLE;
++ ctrl1 = chan->id << GDMA_REG_CTRL1_NEXT_SHIFT;
++
++ chan->next_sg++;
++ gdma_dma_write(dma_dev, GDMA_REG_SRC_ADDR(chan->id), src_addr);
++ gdma_dma_write(dma_dev, GDMA_REG_DST_ADDR(chan->id), dst_addr);
++ gdma_dma_write(dma_dev, GDMA_REG_CTRL1(chan->id), ctrl1);
++
++ /* make sure next_sg is update */
++ wmb();
++ gdma_dma_write(dma_dev, GDMA_REG_CTRL0(chan->id), ctrl0);
++
++ return 0;
++}
++
++static void rt3883_dump_reg(struct gdma_dma_dev *dma_dev, int id)
++{
++ dev_dbg(dma_dev->ddev.dev, "chan %d, src %08x, dst %08x, ctr0 %08x, " \
++ "ctr1 %08x, unmask %08x, done %08x, " \
++ "req %08x, ack %08x, fin %08x\n", id,
++ gdma_dma_read(dma_dev, GDMA_REG_SRC_ADDR(id)),
++ gdma_dma_read(dma_dev, GDMA_REG_DST_ADDR(id)),
++ gdma_dma_read(dma_dev, GDMA_REG_CTRL0(id)),
++ gdma_dma_read(dma_dev, GDMA_REG_CTRL1(id)),
++ gdma_dma_read(dma_dev, GDMA_REG_UNMASK_INT),
++ gdma_dma_read(dma_dev, GDMA_REG_DONE_INT),
++ gdma_dma_read(dma_dev, GDMA_REG_REQSTS),
++ gdma_dma_read(dma_dev, GDMA_REG_ACKSTS),
++ gdma_dma_read(dma_dev, GDMA_REG_FINSTS));
++}
++
++static int rt3883_gdma_start_transfer(struct gdma_dmaengine_chan *chan)
++{
++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
++ dma_addr_t src_addr, dst_addr;
++ struct gdma_dma_sg *sg;
++ uint32_t ctrl0, ctrl1;
++
++ /* verify chan is already stopped */
++ ctrl0 = gdma_dma_read(dma_dev, GDMA_REG_CTRL0(chan->id));
++ if (unlikely(ctrl0 & GDMA_REG_CTRL0_ENABLE)) {
++ dev_err(dma_dev->ddev.dev, "chan %d is start(%08x).\n",
++ chan->id, ctrl0);
++ rt3883_dump_reg(dma_dev, chan->id);
++ return -EINVAL;
++ }
++
++ sg = &chan->desc->sg[chan->next_sg];
++ if (chan->desc->direction == DMA_MEM_TO_DEV) {
++ src_addr = sg->src_addr;
++ dst_addr = chan->fifo_addr;
++ ctrl0 = GDMA_REG_CTRL0_DST_ADDR_FIXED;
++ ctrl1 = (32 << GDMA_REG_CTRL1_SRC_REQ_SHIFT) | \
++ (chan->slave_id << GDMA_REG_CTRL1_DST_REQ_SHIFT);
++ } else if (chan->desc->direction == DMA_DEV_TO_MEM) {
++ src_addr = chan->fifo_addr;
++ dst_addr = sg->dst_addr;
++ ctrl0 = GDMA_REG_CTRL0_SRC_ADDR_FIXED;
++ ctrl1 = (chan->slave_id << GDMA_REG_CTRL1_SRC_REQ_SHIFT) | \
++ (32 << GDMA_REG_CTRL1_DST_REQ_SHIFT) | \
++ GDMA_REG_CTRL1_COHERENT;
++ } else if (chan->desc->direction == DMA_MEM_TO_MEM) {
++ src_addr = sg->src_addr;
++ dst_addr = sg->dst_addr;
++ ctrl0 = GDMA_REG_CTRL0_SW_MODE;
++ ctrl1 = (32 << GDMA_REG_CTRL1_SRC_REQ_SHIFT) | \
++ (32 << GDMA_REG_CTRL1_DST_REQ_SHIFT) | \
++ GDMA_REG_CTRL1_COHERENT;
++ } else {
++ dev_err(dma_dev->ddev.dev, "direction type %d error\n",
++ chan->desc->direction);
++ return -EINVAL;
++ }
++
++ ctrl0 |= (sg->len << GDMA_REG_CTRL0_TX_SHIFT) | \
++ (chan->burst_size << GDMA_REG_CTRL0_BURST_SHIFT) | \
++ GDMA_REG_CTRL0_DONE_INT | GDMA_REG_CTRL0_ENABLE;
++ ctrl1 |= chan->id << GDMA_REG_CTRL1_NEXT_SHIFT;
++
++ chan->next_sg++;
++ gdma_dma_write(dma_dev, GDMA_REG_SRC_ADDR(chan->id), src_addr);
++ gdma_dma_write(dma_dev, GDMA_REG_DST_ADDR(chan->id), dst_addr);
++ gdma_dma_write(dma_dev, GDMA_REG_CTRL1(chan->id), ctrl1);
++
++ /* make sure next_sg is update */
++ wmb();
++ gdma_dma_write(dma_dev, GDMA_REG_CTRL0(chan->id), ctrl0);
++
++ return 0;
++}
++
++static inline int gdma_start_transfer(struct gdma_dma_dev *dma_dev,
++ struct gdma_dmaengine_chan *chan)
++{
++ return dma_dev->data->start_transfer(chan);
++}
++
++static int gdma_next_desc(struct gdma_dmaengine_chan *chan)
++{
++ struct virt_dma_desc *vdesc;
++
++ vdesc = vchan_next_desc(&chan->vchan);
++ if (!vdesc) {
++ chan->desc = NULL;
++ return 0;
++ }
++ chan->desc = to_gdma_dma_desc(vdesc);
++ chan->next_sg = 0;
++
++ return 1;
++}
++
++static void gdma_dma_chan_irq(struct gdma_dma_dev *dma_dev,
++ struct gdma_dmaengine_chan *chan)
++{
++ struct gdma_dma_desc *desc;
++ unsigned long flags;
++ int chan_issued;
++
++ chan_issued = 0;
++ spin_lock_irqsave(&chan->vchan.lock, flags);
++ desc = chan->desc;
++ if (desc) {
++ if (desc->cyclic) {
++ vchan_cyclic_callback(&desc->vdesc);
++ if (chan->next_sg == desc->num_sgs)
++ chan->next_sg = 0;
++ chan_issued = 1;
++ } else {
++ desc->residue -= desc->sg[chan->next_sg - 1].len;
++ if (chan->next_sg == desc->num_sgs) {
++ list_del(&desc->vdesc.node);
++ vchan_cookie_complete(&desc->vdesc);
++ chan_issued = gdma_next_desc(chan);
++ } else
++ chan_issued = 1;
++ }
++ } else
++ dev_dbg(dma_dev->ddev.dev, "chan %d no desc to complete\n",
++ chan->id);
++ if (chan_issued)
++ set_bit(chan->id, &dma_dev->chan_issued);
++ spin_unlock_irqrestore(&chan->vchan.lock, flags);
++}
++
++static irqreturn_t gdma_dma_irq(int irq, void *devid)
++{
++ struct gdma_dma_dev *dma_dev = devid;
++ u32 done, done_reg;
++ unsigned int i;
++
++ done_reg = dma_dev->data->done_int_reg;
++ done = gdma_dma_read(dma_dev, done_reg);
++ if (unlikely(!done))
++ return IRQ_NONE;
++
++ /* clean done bits */
++ gdma_dma_write(dma_dev, done_reg, done);
++
++ i = 0;
++ while (done) {
++ if (done & 0x1) {
++ gdma_dma_chan_irq(dma_dev, &dma_dev->chan[i]);
++ atomic_dec(&dma_dev->cnt);
++ }
++ done >>= 1;
++ i++;
++ }
++
++ /* start only have work to do */
++ if (dma_dev->chan_issued)
++ tasklet_schedule(&dma_dev->task);
++
++ return IRQ_HANDLED;
++}
++
++static void gdma_dma_issue_pending(struct dma_chan *c)
++{
++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
++ struct gdma_dma_dev *dma_dev = gdma_dma_chan_get_dev(chan);
++ unsigned long flags;
++
++ spin_lock_irqsave(&chan->vchan.lock, flags);
++ if (vchan_issue_pending(&chan->vchan) && !chan->desc) {
++ if (gdma_next_desc(chan)) {
++ set_bit(chan->id, &dma_dev->chan_issued);
++ tasklet_schedule(&dma_dev->task);
++ } else
++ dev_dbg(dma_dev->ddev.dev, "chan %d no desc to issue\n",
++ chan->id);
++ }
++ spin_unlock_irqrestore(&chan->vchan.lock, flags);
++}
++
++static struct dma_async_tx_descriptor *gdma_dma_prep_slave_sg(
++ struct dma_chan *c, struct scatterlist *sgl,
++ unsigned int sg_len, enum dma_transfer_direction direction,
++ unsigned long flags, void *context)
++{
++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
++ struct gdma_dma_desc *desc;
++ struct scatterlist *sg;
++ unsigned int i;
++
++ desc = gdma_dma_alloc_desc(sg_len);
++ if (!desc) {
++ dev_err(c->device->dev, "alloc sg decs error\n");
++ return NULL;
++ }
++ desc->residue = 0;
++
++ for_each_sg(sgl, sg, sg_len, i) {
++ if (direction == DMA_MEM_TO_DEV)
++ desc->sg[i].src_addr = sg_dma_address(sg);
++ else if (direction == DMA_DEV_TO_MEM)
++ desc->sg[i].dst_addr = sg_dma_address(sg);
++ else {
++ dev_err(c->device->dev, "direction type %d error\n",
++ direction);
++ goto free_desc;
++ }
++
++ if (unlikely(sg_dma_len(sg) > GDMA_REG_CTRL0_TX_MASK)) {
++ dev_err(c->device->dev, "sg len too large %d\n",
++ sg_dma_len(sg));
++ goto free_desc;
++ }
++ desc->sg[i].len = sg_dma_len(sg);
++ desc->residue += sg_dma_len(sg);
++ }
++
++ desc->num_sgs = sg_len;
++ desc->direction = direction;
++ desc->cyclic = false;
++
++ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
++
++free_desc:
++ kfree(desc);
++ return NULL;
++}
++
++static struct dma_async_tx_descriptor * gdma_dma_prep_dma_memcpy(
++ struct dma_chan *c, dma_addr_t dest, dma_addr_t src,
++ size_t len, unsigned long flags)
++{
++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
++ struct gdma_dma_desc *desc;
++ unsigned int num_periods, i;
++ size_t xfer_count;
++
++ if (len <= 0)
++ return NULL;
++
++ chan->burst_size = gdma_dma_maxburst(len >> 2);
++
++ xfer_count = GDMA_REG_CTRL0_TX_MASK;
++ num_periods = DIV_ROUND_UP(len, xfer_count);
++
++ desc = gdma_dma_alloc_desc(num_periods);
++ if (!desc) {
++ dev_err(c->device->dev, "alloc memcpy decs error\n");
++ return NULL;
++ }
++ desc->residue = len;
++
++ for (i = 0; i < num_periods; i++) {
++ desc->sg[i].src_addr = src;
++ desc->sg[i].dst_addr = dest;
++ if (len > xfer_count) {
++ desc->sg[i].len = xfer_count;
++ } else {
++ desc->sg[i].len = len;
++ }
++ src += desc->sg[i].len;
++ dest += desc->sg[i].len;
++ len -= desc->sg[i].len;
++ }
++
++ desc->num_sgs = num_periods;
++ desc->direction = DMA_MEM_TO_MEM;
++ desc->cyclic = false;
++
++ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
++}
++
++static struct dma_async_tx_descriptor *gdma_dma_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 gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
++ struct gdma_dma_desc *desc;
++ unsigned int num_periods, i;
++
++ if (buf_len % period_len)
++ return NULL;
++
++ if (period_len > GDMA_REG_CTRL0_TX_MASK) {
++ dev_err(c->device->dev, "cyclic len too large %d\n",
++ period_len);
++ return NULL;
++ }
++
++ num_periods = buf_len / period_len;
++ desc = gdma_dma_alloc_desc(num_periods);
++ if (!desc) {
++ dev_err(c->device->dev, "alloc cyclic decs error\n");
++ return NULL;
++ }
++ desc->residue = buf_len;
++
++ for (i = 0; i < num_periods; i++) {
++ if (direction == DMA_MEM_TO_DEV)
++ desc->sg[i].src_addr = buf_addr;
++ else if (direction == DMA_DEV_TO_MEM)
++ desc->sg[i].dst_addr = buf_addr;
++ else {
++ dev_err(c->device->dev, "direction type %d error\n",
++ direction);
++ goto free_desc;
++ }
++ desc->sg[i].len = period_len;
++ buf_addr += period_len;
++ }
++
++ desc->num_sgs = num_periods;
++ desc->direction = direction;
++ desc->cyclic = true;
++
++ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
++
++free_desc:
++ kfree(desc);
++ return NULL;
++}
++
++static enum dma_status gdma_dma_tx_status(struct dma_chan *c,
++ dma_cookie_t cookie, struct dma_tx_state *state)
++{
++ struct gdma_dmaengine_chan *chan = to_gdma_dma_chan(c);
++ struct virt_dma_desc *vdesc;
++ enum dma_status status;
++ unsigned long flags;
++ struct gdma_dma_desc *desc;
++
++ status = dma_cookie_status(c, cookie, state);
++ if (status == DMA_COMPLETE || !state)
++ return status;
++
++ spin_lock_irqsave(&chan->vchan.lock, flags);
++ desc = chan->desc;
++ if (desc && (cookie == desc->vdesc.tx.cookie)) {
++ /*
++ * We never update edesc->residue in the cyclic case, so we
++ * can tell the remaining room to the end of the circular
++ * buffer.
++ */
++ if (desc->cyclic)
++ state->residue = desc->residue -
++ ((chan->next_sg - 1) * desc->sg[0].len);
++ else
++ state->residue = desc->residue;
++ } else if ((vdesc = vchan_find_desc(&chan->vchan, cookie)))
++ state->residue = to_gdma_dma_desc(vdesc)->residue;
++ spin_unlock_irqrestore(&chan->vchan.lock, flags);
++
++ dev_dbg(c->device->dev, "tx residue %d bytes\n", state->residue);
++
++ return status;
++}
++
++static void gdma_dma_free_chan_resources(struct dma_chan *c)
++{
++ vchan_free_chan_resources(to_virt_chan(c));
++}
++
++static void gdma_dma_desc_free(struct virt_dma_desc *vdesc)
++{
++ kfree(container_of(vdesc, struct gdma_dma_desc, vdesc));
++}
++
++static void gdma_dma_tasklet(unsigned long arg)
++{
++ struct gdma_dma_dev *dma_dev = (struct gdma_dma_dev *)arg;
++ struct gdma_dmaengine_chan *chan;
++ static unsigned int last_chan;
++ unsigned int i, chan_mask;
++
++ /* record last chan to round robin all chans */
++ i = last_chan;
++ chan_mask = dma_dev->data->chancnt - 1;
++ do {
++ /*
++ * on mt7621. when verify with dmatest with all
++ * channel is enable. we need to limit only two
++ * channel is working at the same time. otherwise the
++ * data will have problem.
++ */
++ if (atomic_read(&dma_dev->cnt) >= 2) {
++ last_chan = i;
++ break;
++ }
++
++ if (test_and_clear_bit(i, &dma_dev->chan_issued)) {
++ chan = &dma_dev->chan[i];
++ if (chan->desc) {
++ atomic_inc(&dma_dev->cnt);
++ gdma_start_transfer(dma_dev, chan);
++ } else
++ dev_dbg(dma_dev->ddev.dev, "chan %d no desc to issue\n", chan->id);
++
++ if (!dma_dev->chan_issued)
++ break;
++ }
++
++ i = (i + 1) & chan_mask;
++ } while (i != last_chan);
++}
++
++static void rt305x_gdma_init(struct gdma_dma_dev *dma_dev)
++{
++ uint32_t gct;
++
++ /* all chans round robin */
++ gdma_dma_write(dma_dev, GDMA_RT305X_GCT, GDMA_REG_GCT_ARBIT_RR);
++
++ gct = gdma_dma_read(dma_dev, GDMA_RT305X_GCT);
++ dev_info(dma_dev->ddev.dev, "revision: %d, channels: %d\n",
++ (gct >> GDMA_REG_GCT_VER_SHIFT) & GDMA_REG_GCT_VER_MASK,
++ 8 << ((gct >> GDMA_REG_GCT_CHAN_SHIFT) &
++ GDMA_REG_GCT_CHAN_MASK));
++}
++
++static void rt3883_gdma_init(struct gdma_dma_dev *dma_dev)
++{
++ uint32_t gct;
++
++ /* all chans round robin */
++ gdma_dma_write(dma_dev, GDMA_REG_GCT, GDMA_REG_GCT_ARBIT_RR);
++
++ gct = gdma_dma_read(dma_dev, GDMA_REG_GCT);
++ dev_info(dma_dev->ddev.dev, "revision: %d, channels: %d\n",
++ (gct >> GDMA_REG_GCT_VER_SHIFT) & GDMA_REG_GCT_VER_MASK,
++ 8 << ((gct >> GDMA_REG_GCT_CHAN_SHIFT) &
++ GDMA_REG_GCT_CHAN_MASK));
++}
++
++static struct gdma_data rt305x_gdma_data = {
++ .chancnt = 8,
++ .done_int_reg = GDMA_RT305X_STATUS_INT,
++ .init = rt305x_gdma_init,
++ .start_transfer = rt305x_gdma_start_transfer,
++};
++
++static struct gdma_data rt3883_gdma_data = {
++ .chancnt = 16,
++ .done_int_reg = GDMA_REG_DONE_INT,
++ .init = rt3883_gdma_init,
++ .start_transfer = rt3883_gdma_start_transfer,
++};
++
++static const struct of_device_id gdma_of_match_table[] = {
++ { .compatible = "ralink,rt305x-gdma", .data = &rt305x_gdma_data },
++ { .compatible = "ralink,rt3883-gdma", .data = &rt3883_gdma_data },
++ { },
++};
++
++static int gdma_dma_probe(struct platform_device *pdev)
++{
++ const struct of_device_id *match;
++ struct gdma_dmaengine_chan *chan;
++ struct gdma_dma_dev *dma_dev;
++ struct dma_device *dd;
++ unsigned int i;
++ struct resource *res;
++ int ret;
++ int irq;
++ void __iomem *base;
++ struct gdma_data *data;
++
++ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
++ if (ret)
++ return ret;
++
++ match = of_match_device(gdma_of_match_table, &pdev->dev);
++ if (!match)
++ return -EINVAL;
++ data = (struct gdma_data *) match->data;
++
++ dma_dev = devm_kzalloc(&pdev->dev, sizeof(*dma_dev) +
++ (sizeof(struct gdma_dmaengine_chan) * data->chancnt),
++ GFP_KERNEL);
++ if (!dma_dev) {
++ dev_err(&pdev->dev, "alloc dma device failed\n");
++ return -EINVAL;
++ }
++ dma_dev->data = data;
++
++ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++ base = devm_ioremap_resource(&pdev->dev, res);
++ if (IS_ERR(base))
++ return PTR_ERR(base);
++ dma_dev->base = base;
++ tasklet_init(&dma_dev->task, gdma_dma_tasklet, (unsigned long)dma_dev);
++
++ irq = platform_get_irq(pdev, 0);
++ if (irq < 0) {
++ dev_err(&pdev->dev, "failed to get irq\n");
++ return -EINVAL;
++ }
++ ret = devm_request_irq(&pdev->dev, irq, gdma_dma_irq,
++ 0, dev_name(&pdev->dev), dma_dev);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to request irq\n");
++ return ret;
++ }
++
++ device_reset(&pdev->dev);
++
++ dd = &dma_dev->ddev;
++ 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->device_free_chan_resources = gdma_dma_free_chan_resources;
++ dd->device_prep_dma_memcpy = gdma_dma_prep_dma_memcpy;
++ dd->device_prep_slave_sg = gdma_dma_prep_slave_sg;
++ dd->device_prep_dma_cyclic = gdma_dma_prep_dma_cyclic;
++ dd->device_config = gdma_dma_config;
++ dd->device_terminate_all = gdma_dma_terminate_all;
++ dd->device_tx_status = gdma_dma_tx_status;
++ dd->device_issue_pending = gdma_dma_issue_pending;
++
++ dd->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
++ dd->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
++ dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
++ dd->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
++
++ dd->dev = &pdev->dev;
++ dd->dev->dma_parms = &dma_dev->dma_parms;
++ dma_set_max_seg_size(dd->dev, GDMA_REG_CTRL0_TX_MASK);
++ INIT_LIST_HEAD(&dd->channels);
++
++ for (i = 0; i < data->chancnt; i++) {
++ chan = &dma_dev->chan[i];
++ chan->id = i;
++ chan->vchan.desc_free = gdma_dma_desc_free;
++ vchan_init(&chan->vchan, dd);
++ }
++
++ /* init hardware */
++ data->init(dma_dev);
++
++ ret = dma_async_device_register(dd);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to register dma device\n");
++ return ret;
++ }
++
++ ret = of_dma_controller_register(pdev->dev.of_node,
++ of_dma_xlate_by_chan_id, dma_dev);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to register of dma controller\n");
++ goto err_unregister;
++ }
++
++ platform_set_drvdata(pdev, dma_dev);
++
++ return 0;
++
++err_unregister:
++ dma_async_device_unregister(dd);
++ return ret;
++}
++
++static int gdma_dma_remove(struct platform_device *pdev)
++{
++ struct gdma_dma_dev *dma_dev = platform_get_drvdata(pdev);
++
++ tasklet_kill(&dma_dev->task);
++ of_dma_controller_free(pdev->dev.of_node);
++ dma_async_device_unregister(&dma_dev->ddev);
++
++ return 0;
++}
++
++static struct platform_driver gdma_dma_driver = {
++ .probe = gdma_dma_probe,
++ .remove = gdma_dma_remove,
++ .driver = {
++ .name = "gdma-rt2880",
++ .of_match_table = gdma_of_match_table,
++ },
++};
++module_platform_driver(gdma_dma_driver);
++
++MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
++MODULE_DESCRIPTION("Ralink/MTK DMA driver");
++MODULE_LICENSE("GPL v2");
+--- a/include/linux/dmaengine.h
++++ b/include/linux/dmaengine.h
+@@ -514,6 +514,7 @@ static inline void dma_set_unmap(struct
+ struct dmaengine_unmap_data *
+ dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags);
+ void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap);
++struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
+ #else
+ static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
+ struct dmaengine_unmap_data *unmap)
+--- /dev/null
++++ b/drivers/dma/mtk-hsdma.c
+@@ -0,0 +1,767 @@
++/*
++ * Copyright (C) 2015, Michael Lee <igvtee@gmail.com>
++ * MTK HSDMA support
++ *
++ * 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/dmaengine.h>
++#include <linux/dma-mapping.h>
++#include <linux/err.h>
++#include <linux/init.h>
++#include <linux/list.h>
++#include <linux/module.h>
++#include <linux/platform_device.h>
++#include <linux/slab.h>
++#include <linux/spinlock.h>
++#include <linux/irq.h>
++#include <linux/of_dma.h>
++#include <linux/reset.h>
++#include <linux/of_device.h>
++
++#include "virt-dma.h"
++
++#define HSDMA_BASE_OFFSET 0x800
++
++#define HSDMA_REG_TX_BASE 0x00
++#define HSDMA_REG_TX_CNT 0x04
++#define HSDMA_REG_TX_CTX 0x08
++#define HSDMA_REG_TX_DTX 0x0c
++#define HSDMA_REG_RX_BASE 0x100
++#define HSDMA_REG_RX_CNT 0x104
++#define HSDMA_REG_RX_CRX 0x108
++#define HSDMA_REG_RX_DRX 0x10c
++#define HSDMA_REG_INFO 0x200
++#define HSDMA_REG_GLO_CFG 0x204
++#define HSDMA_REG_RST_CFG 0x208
++#define HSDMA_REG_DELAY_INT 0x20c
++#define HSDMA_REG_FREEQ_THRES 0x210
++#define HSDMA_REG_INT_STATUS 0x220
++#define HSDMA_REG_INT_MASK 0x228
++#define HSDMA_REG_SCH_Q01 0x280
++#define HSDMA_REG_SCH_Q23 0x284
++
++#define HSDMA_DESCS_MAX 0xfff
++#define HSDMA_DESCS_NUM 8
++#define HSDMA_DESCS_MASK (HSDMA_DESCS_NUM - 1)
++#define HSDMA_NEXT_DESC(x) (((x) + 1) & HSDMA_DESCS_MASK)
++
++/* HSDMA_REG_INFO */
++#define HSDMA_INFO_INDEX_MASK 0xf
++#define HSDMA_INFO_INDEX_SHIFT 24
++#define HSDMA_INFO_BASE_MASK 0xff
++#define HSDMA_INFO_BASE_SHIFT 16
++#define HSDMA_INFO_RX_MASK 0xff
++#define HSDMA_INFO_RX_SHIFT 8
++#define HSDMA_INFO_TX_MASK 0xff
++#define HSDMA_INFO_TX_SHIFT 0
++
++/* HSDMA_REG_GLO_CFG */
++#define HSDMA_GLO_TX_2B_OFFSET BIT(31)
++#define HSDMA_GLO_CLK_GATE BIT(30)
++#define HSDMA_GLO_BYTE_SWAP BIT(29)
++#define HSDMA_GLO_MULTI_DMA BIT(10)
++#define HSDMA_GLO_TWO_BUF BIT(9)
++#define HSDMA_GLO_32B_DESC BIT(8)
++#define HSDMA_GLO_BIG_ENDIAN BIT(7)
++#define HSDMA_GLO_TX_DONE BIT(6)
++#define HSDMA_GLO_BT_MASK 0x3
++#define HSDMA_GLO_BT_SHIFT 4
++#define HSDMA_GLO_RX_BUSY BIT(3)
++#define HSDMA_GLO_RX_DMA BIT(2)
++#define HSDMA_GLO_TX_BUSY BIT(1)
++#define HSDMA_GLO_TX_DMA BIT(0)
++
++#define HSDMA_BT_SIZE_16BYTES (0 << HSDMA_GLO_BT_SHIFT)
++#define HSDMA_BT_SIZE_32BYTES (1 << HSDMA_GLO_BT_SHIFT)
++#define HSDMA_BT_SIZE_64BYTES (2 << HSDMA_GLO_BT_SHIFT)
++#define HSDMA_BT_SIZE_128BYTES (3 << HSDMA_GLO_BT_SHIFT)
++
++#define HSDMA_GLO_DEFAULT (HSDMA_GLO_MULTI_DMA | \
++ HSDMA_GLO_RX_DMA | HSDMA_GLO_TX_DMA | HSDMA_BT_SIZE_32BYTES)
++
++/* HSDMA_REG_RST_CFG */
++#define HSDMA_RST_RX_SHIFT 16
++#define HSDMA_RST_TX_SHIFT 0
++
++/* HSDMA_REG_DELAY_INT */
++#define HSDMA_DELAY_INT_EN BIT(15)
++#define HSDMA_DELAY_PEND_OFFSET 8
++#define HSDMA_DELAY_TIME_OFFSET 0
++#define HSDMA_DELAY_TX_OFFSET 16
++#define HSDMA_DELAY_RX_OFFSET 0
++
++#define HSDMA_DELAY_INIT(x) (HSDMA_DELAY_INT_EN | \
++ ((x) << HSDMA_DELAY_PEND_OFFSET))
++#define HSDMA_DELAY(x) ((HSDMA_DELAY_INIT(x) << \
++ HSDMA_DELAY_TX_OFFSET) | HSDMA_DELAY_INIT(x))
++
++/* HSDMA_REG_INT_STATUS */
++#define HSDMA_INT_DELAY_RX_COH BIT(31)
++#define HSDMA_INT_DELAY_RX_INT BIT(30)
++#define HSDMA_INT_DELAY_TX_COH BIT(29)
++#define HSDMA_INT_DELAY_TX_INT BIT(28)
++#define HSDMA_INT_RX_MASK 0x3
++#define HSDMA_INT_RX_SHIFT 16
++#define HSDMA_INT_RX_Q0 BIT(16)
++#define HSDMA_INT_TX_MASK 0xf
++#define HSDMA_INT_TX_SHIFT 0
++#define HSDMA_INT_TX_Q0 BIT(0)
++
++/* tx/rx dma desc flags */
++#define HSDMA_PLEN_MASK 0x3fff
++#define HSDMA_DESC_DONE BIT(31)
++#define HSDMA_DESC_LS0 BIT(30)
++#define HSDMA_DESC_PLEN0(_x) (((_x) & HSDMA_PLEN_MASK) << 16)
++#define HSDMA_DESC_TAG BIT(15)
++#define HSDMA_DESC_LS1 BIT(14)
++#define HSDMA_DESC_PLEN1(_x) ((_x) & HSDMA_PLEN_MASK)
++
++/* align 4 bytes */
++#define HSDMA_ALIGN_SIZE 3
++/* align size 128bytes */
++#define HSDMA_MAX_PLEN 0x3f80
++
++struct hsdma_desc {
++ u32 addr0;
++ u32 flags;
++ u32 addr1;
++ u32 unused;
++};
++
++struct mtk_hsdma_sg {
++ dma_addr_t src_addr;
++ dma_addr_t dst_addr;
++ u32 len;
++};
++
++struct mtk_hsdma_desc {
++ struct virt_dma_desc vdesc;
++ unsigned int num_sgs;
++ struct mtk_hsdma_sg sg[1];
++};
++
++struct mtk_hsdma_chan {
++ struct virt_dma_chan vchan;
++ unsigned int id;
++ dma_addr_t desc_addr;
++ int tx_idx;
++ int rx_idx;
++ struct hsdma_desc *tx_ring;
++ struct hsdma_desc *rx_ring;
++ struct mtk_hsdma_desc *desc;
++ unsigned int next_sg;
++};
++
++struct mtk_hsdam_engine {
++ struct dma_device ddev;
++ struct device_dma_parameters dma_parms;
++ void __iomem *base;
++ struct tasklet_struct task;
++ volatile unsigned long chan_issued;
++
++ struct mtk_hsdma_chan chan[1];
++};
++
++static inline struct mtk_hsdam_engine *mtk_hsdma_chan_get_dev(
++ struct mtk_hsdma_chan *chan)
++{
++ return container_of(chan->vchan.chan.device, struct mtk_hsdam_engine,
++ ddev);
++}
++
++static inline struct mtk_hsdma_chan *to_mtk_hsdma_chan(struct dma_chan *c)
++{
++ return container_of(c, struct mtk_hsdma_chan, vchan.chan);
++}
++
++static inline struct mtk_hsdma_desc *to_mtk_hsdma_desc(
++ struct virt_dma_desc *vdesc)
++{
++ return container_of(vdesc, struct mtk_hsdma_desc, vdesc);
++}
++
++static inline u32 mtk_hsdma_read(struct mtk_hsdam_engine *hsdma, u32 reg)
++{
++ return readl(hsdma->base + reg);
++}
++
++static inline void mtk_hsdma_write(struct mtk_hsdam_engine *hsdma,
++ unsigned reg, u32 val)
++{
++ writel(val, hsdma->base + reg);
++}
++
++static void mtk_hsdma_reset_chan(struct mtk_hsdam_engine *hsdma,
++ struct mtk_hsdma_chan *chan)
++{
++ chan->tx_idx = 0;
++ chan->rx_idx = HSDMA_DESCS_NUM - 1;
++
++ mtk_hsdma_write(hsdma, HSDMA_REG_TX_CTX, chan->tx_idx);
++ mtk_hsdma_write(hsdma, HSDMA_REG_RX_CRX, chan->rx_idx);
++
++ mtk_hsdma_write(hsdma, HSDMA_REG_RST_CFG,
++ 0x1 << (chan->id + HSDMA_RST_TX_SHIFT));
++ mtk_hsdma_write(hsdma, HSDMA_REG_RST_CFG,
++ 0x1 << (chan->id + HSDMA_RST_RX_SHIFT));
++}
++
++static void hsdma_dump_reg(struct mtk_hsdam_engine *hsdma)
++{
++ dev_dbg(hsdma->ddev.dev, "tbase %08x, tcnt %08x, " \
++ "tctx %08x, tdtx: %08x, rbase %08x, " \
++ "rcnt %08x, rctx %08x, rdtx %08x\n",
++ mtk_hsdma_read(hsdma, HSDMA_REG_TX_BASE),
++ mtk_hsdma_read(hsdma, HSDMA_REG_TX_CNT),
++ mtk_hsdma_read(hsdma, HSDMA_REG_TX_CTX),
++ mtk_hsdma_read(hsdma, HSDMA_REG_TX_DTX),
++ mtk_hsdma_read(hsdma, HSDMA_REG_RX_BASE),
++ mtk_hsdma_read(hsdma, HSDMA_REG_RX_CNT),
++ mtk_hsdma_read(hsdma, HSDMA_REG_RX_CRX),
++ mtk_hsdma_read(hsdma, HSDMA_REG_RX_DRX));
++
++ dev_dbg(hsdma->ddev.dev, "info %08x, glo %08x, delay %08x, " \
++ "intr_stat %08x, intr_mask %08x\n",
++ mtk_hsdma_read(hsdma, HSDMA_REG_INFO),
++ mtk_hsdma_read(hsdma, HSDMA_REG_GLO_CFG),
++ mtk_hsdma_read(hsdma, HSDMA_REG_DELAY_INT),
++ mtk_hsdma_read(hsdma, HSDMA_REG_INT_STATUS),
++ mtk_hsdma_read(hsdma, HSDMA_REG_INT_MASK));
++}
++
++static void hsdma_dump_desc(struct mtk_hsdam_engine *hsdma,
++ struct mtk_hsdma_chan *chan)
++{
++ struct hsdma_desc *tx_desc;
++ struct hsdma_desc *rx_desc;
++ int i;
++
++ dev_dbg(hsdma->ddev.dev, "tx idx: %d, rx idx: %d\n",
++ chan->tx_idx, chan->rx_idx);
++
++ for (i = 0; i < HSDMA_DESCS_NUM; i++) {
++ tx_desc = &chan->tx_ring[i];
++ rx_desc = &chan->rx_ring[i];
++
++ dev_dbg(hsdma->ddev.dev, "%d tx addr0: %08x, flags %08x, " \
++ "tx addr1: %08x, rx addr0 %08x, flags %08x\n",
++ i, tx_desc->addr0, tx_desc->flags, \
++ tx_desc->addr1, rx_desc->addr0, rx_desc->flags);
++ }
++}
++
++static void mtk_hsdma_reset(struct mtk_hsdam_engine *hsdma,
++ struct mtk_hsdma_chan *chan)
++{
++ int i;
++
++ /* disable dma */
++ mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, 0);
++
++ /* disable intr */
++ mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, 0);
++
++ /* init desc value */
++ for (i = 0; i < HSDMA_DESCS_NUM; i++) {
++ chan->tx_ring[i].addr0 = 0;
++ chan->tx_ring[i].flags = HSDMA_DESC_LS0 |
++ HSDMA_DESC_DONE;
++ }
++ for (i = 0; i < HSDMA_DESCS_NUM; i++) {
++ chan->rx_ring[i].addr0 = 0;
++ chan->rx_ring[i].flags = 0;
++ }
++
++ /* reset */
++ mtk_hsdma_reset_chan(hsdma, chan);
++
++ /* enable intr */
++ mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, HSDMA_INT_RX_Q0);
++
++ /* enable dma */
++ mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, HSDMA_GLO_DEFAULT);
++}
++
++static int mtk_hsdma_terminate_all(struct dma_chan *c)
++{
++ struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
++ struct mtk_hsdam_engine *hsdma = mtk_hsdma_chan_get_dev(chan);
++ unsigned long timeout;
++ LIST_HEAD(head);
++
++ spin_lock_bh(&chan->vchan.lock);
++ chan->desc = NULL;
++ clear_bit(chan->id, &hsdma->chan_issued);
++ vchan_get_all_descriptors(&chan->vchan, &head);
++ spin_unlock_bh(&chan->vchan.lock);
++
++ vchan_dma_desc_free_list(&chan->vchan, &head);
++
++ /* wait dma transfer complete */
++ timeout = jiffies + msecs_to_jiffies(2000);
++ while (mtk_hsdma_read(hsdma, HSDMA_REG_GLO_CFG) &
++ (HSDMA_GLO_RX_BUSY | HSDMA_GLO_TX_BUSY)) {
++ if (time_after_eq(jiffies, timeout)) {
++ hsdma_dump_desc(hsdma, chan);
++ mtk_hsdma_reset(hsdma, chan);
++ dev_err(hsdma->ddev.dev, "timeout, reset it\n");
++ break;
++ }
++ cpu_relax();
++ }
++
++ return 0;
++}
++
++static int mtk_hsdma_start_transfer(struct mtk_hsdam_engine *hsdma,
++ struct mtk_hsdma_chan *chan)
++{
++ dma_addr_t src, dst;
++ size_t len, tlen;
++ struct hsdma_desc *tx_desc, *rx_desc;
++ struct mtk_hsdma_sg *sg;
++ unsigned int i;
++ int rx_idx;
++
++ sg = &chan->desc->sg[0];
++ len = sg->len;
++ chan->desc->num_sgs = DIV_ROUND_UP(len, HSDMA_MAX_PLEN);
++
++ /* tx desc */
++ src = sg->src_addr;
++ for (i = 0; i < chan->desc->num_sgs; i++) {
++ if (len > HSDMA_MAX_PLEN)
++ tlen = HSDMA_MAX_PLEN;
++ else
++ tlen = len;
++
++ if (i & 0x1) {
++ tx_desc->addr1 = src;
++ tx_desc->flags |= HSDMA_DESC_PLEN1(tlen);
++ } else {
++ tx_desc = &chan->tx_ring[chan->tx_idx];
++ tx_desc->addr0 = src;
++ tx_desc->flags = HSDMA_DESC_PLEN0(tlen);
++
++ /* update index */
++ chan->tx_idx = HSDMA_NEXT_DESC(chan->tx_idx);
++ }
++
++ src += tlen;
++ len -= tlen;
++ }
++ if (i & 0x1)
++ tx_desc->flags |= HSDMA_DESC_LS0;
++ else
++ tx_desc->flags |= HSDMA_DESC_LS1;
++
++ /* rx desc */
++ rx_idx = HSDMA_NEXT_DESC(chan->rx_idx);
++ len = sg->len;
++ dst = sg->dst_addr;
++ for (i = 0; i < chan->desc->num_sgs; i++) {
++ rx_desc = &chan->rx_ring[rx_idx];
++ if (len > HSDMA_MAX_PLEN)
++ tlen = HSDMA_MAX_PLEN;
++ else
++ tlen = len;
++
++ rx_desc->addr0 = dst;
++ rx_desc->flags = HSDMA_DESC_PLEN0(tlen);
++
++ dst += tlen;
++ len -= tlen;
++
++ /* update index */
++ rx_idx = HSDMA_NEXT_DESC(rx_idx);
++ }
++
++ /* make sure desc and index all up to date */
++ wmb();
++ mtk_hsdma_write(hsdma, HSDMA_REG_TX_CTX, chan->tx_idx);
++
++ return 0;
++}
++
++static int gdma_next_desc(struct mtk_hsdma_chan *chan)
++{
++ struct virt_dma_desc *vdesc;
++
++ vdesc = vchan_next_desc(&chan->vchan);
++ if (!vdesc) {
++ chan->desc = NULL;
++ return 0;
++ }
++ chan->desc = to_mtk_hsdma_desc(vdesc);
++ chan->next_sg = 0;
++
++ return 1;
++}
++
++static void mtk_hsdma_chan_done(struct mtk_hsdam_engine *hsdma,
++ struct mtk_hsdma_chan *chan)
++{
++ struct mtk_hsdma_desc *desc;
++ int chan_issued;
++
++ chan_issued = 0;
++ spin_lock_bh(&chan->vchan.lock);
++ desc = chan->desc;
++ if (likely(desc)) {
++ if (chan->next_sg == desc->num_sgs) {
++ list_del(&desc->vdesc.node);
++ vchan_cookie_complete(&desc->vdesc);
++ chan_issued = gdma_next_desc(chan);
++ }
++ } else
++ dev_dbg(hsdma->ddev.dev, "no desc to complete\n");
++
++ if (chan_issued)
++ set_bit(chan->id, &hsdma->chan_issued);
++ spin_unlock_bh(&chan->vchan.lock);
++}
++
++static irqreturn_t mtk_hsdma_irq(int irq, void *devid)
++{
++ struct mtk_hsdam_engine *hsdma = devid;
++ u32 status;
++
++ status = mtk_hsdma_read(hsdma, HSDMA_REG_INT_STATUS);
++ if (unlikely(!status))
++ return IRQ_NONE;
++
++ if (likely(status & HSDMA_INT_RX_Q0))
++ tasklet_schedule(&hsdma->task);
++ else
++ dev_dbg(hsdma->ddev.dev, "unhandle irq status %08x\n",
++ status);
++ /* clean intr bits */
++ mtk_hsdma_write(hsdma, HSDMA_REG_INT_STATUS, status);
++
++ return IRQ_HANDLED;
++}
++
++static void mtk_hsdma_issue_pending(struct dma_chan *c)
++{
++ struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
++ struct mtk_hsdam_engine *hsdma = mtk_hsdma_chan_get_dev(chan);
++
++ spin_lock_bh(&chan->vchan.lock);
++ if (vchan_issue_pending(&chan->vchan) && !chan->desc) {
++ if (gdma_next_desc(chan)) {
++ set_bit(chan->id, &hsdma->chan_issued);
++ tasklet_schedule(&hsdma->task);
++ } else
++ dev_dbg(hsdma->ddev.dev, "no desc to issue\n");
++ }
++ spin_unlock_bh(&chan->vchan.lock);
++}
++
++static struct dma_async_tx_descriptor * mtk_hsdma_prep_dma_memcpy(
++ struct dma_chan *c, dma_addr_t dest, dma_addr_t src,
++ size_t len, unsigned long flags)
++{
++ struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
++ struct mtk_hsdma_desc *desc;
++
++ if (len <= 0)
++ return NULL;
++
++ desc = kzalloc(sizeof(struct mtk_hsdma_desc), GFP_ATOMIC);
++ if (!desc) {
++ dev_err(c->device->dev, "alloc memcpy decs error\n");
++ return NULL;
++ }
++
++ desc->sg[0].src_addr = src;
++ desc->sg[0].dst_addr = dest;
++ desc->sg[0].len = len;
++
++ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
++}
++
++static enum dma_status mtk_hsdma_tx_status(struct dma_chan *c,
++ dma_cookie_t cookie, struct dma_tx_state *state)
++{
++ return dma_cookie_status(c, cookie, state);
++}
++
++static void mtk_hsdma_free_chan_resources(struct dma_chan *c)
++{
++ vchan_free_chan_resources(to_virt_chan(c));
++}
++
++static void mtk_hsdma_desc_free(struct virt_dma_desc *vdesc)
++{
++ kfree(container_of(vdesc, struct mtk_hsdma_desc, vdesc));
++}
++
++static void mtk_hsdma_tx(struct mtk_hsdam_engine *hsdma)
++{
++ struct mtk_hsdma_chan *chan;
++
++ if (test_and_clear_bit(0, &hsdma->chan_issued)) {
++ chan = &hsdma->chan[0];
++ if (chan->desc) {
++ mtk_hsdma_start_transfer(hsdma, chan);
++ } else
++ dev_dbg(hsdma->ddev.dev,"chan 0 no desc to issue\n");
++ }
++}
++
++static void mtk_hsdma_rx(struct mtk_hsdam_engine *hsdma)
++{
++ struct mtk_hsdma_chan *chan;
++ int next_idx, drx_idx, cnt;
++
++ chan = &hsdma->chan[0];
++ next_idx = HSDMA_NEXT_DESC(chan->rx_idx);
++ drx_idx = mtk_hsdma_read(hsdma, HSDMA_REG_RX_DRX);
++
++ cnt = (drx_idx - next_idx) & HSDMA_DESCS_MASK;
++ if (!cnt)
++ return;
++
++ chan->next_sg += cnt;
++ chan->rx_idx = (chan->rx_idx + cnt) & HSDMA_DESCS_MASK;
++
++ /* update rx crx */
++ wmb();
++ mtk_hsdma_write(hsdma, HSDMA_REG_RX_CRX, chan->rx_idx);
++
++ mtk_hsdma_chan_done(hsdma, chan);
++}
++
++static void mtk_hsdma_tasklet(unsigned long arg)
++{
++ struct mtk_hsdam_engine *hsdma = (struct mtk_hsdam_engine *)arg;
++
++ mtk_hsdma_rx(hsdma);
++ mtk_hsdma_tx(hsdma);
++}
++
++static int mtk_hsdam_alloc_desc(struct mtk_hsdam_engine *hsdma,
++ struct mtk_hsdma_chan *chan)
++{
++ int i;
++
++ chan->tx_ring = dma_alloc_coherent(hsdma->ddev.dev,
++ 2 * HSDMA_DESCS_NUM * sizeof(*chan->tx_ring),
++ &chan->desc_addr, GFP_ATOMIC | __GFP_ZERO);
++ if (!chan->tx_ring)
++ goto no_mem;
++
++ chan->rx_ring = &chan->tx_ring[HSDMA_DESCS_NUM];
++
++ /* init tx ring value */
++ for (i = 0; i < HSDMA_DESCS_NUM; i++)
++ chan->tx_ring[i].flags = HSDMA_DESC_LS0 | HSDMA_DESC_DONE;
++
++ return 0;
++no_mem:
++ return -ENOMEM;
++}
++
++static void mtk_hsdam_free_desc(struct mtk_hsdam_engine *hsdma,
++ struct mtk_hsdma_chan *chan)
++{
++ if (chan->tx_ring) {
++ dma_free_coherent(hsdma->ddev.dev,
++ 2 * HSDMA_DESCS_NUM * sizeof(*chan->tx_ring),
++ chan->tx_ring, chan->desc_addr);
++ chan->tx_ring = NULL;
++ chan->rx_ring = NULL;
++ }
++}
++
++static int mtk_hsdma_init(struct mtk_hsdam_engine *hsdma)
++{
++ struct mtk_hsdma_chan *chan;
++ int ret;
++ u32 reg;
++
++ /* init desc */
++ chan = &hsdma->chan[0];
++ ret = mtk_hsdam_alloc_desc(hsdma, chan);
++ if (ret)
++ return ret;
++
++ /* tx */
++ mtk_hsdma_write(hsdma, HSDMA_REG_TX_BASE, chan->desc_addr);
++ mtk_hsdma_write(hsdma, HSDMA_REG_TX_CNT, HSDMA_DESCS_NUM);
++ /* rx */
++ mtk_hsdma_write(hsdma, HSDMA_REG_RX_BASE, chan->desc_addr +
++ (sizeof(struct hsdma_desc) * HSDMA_DESCS_NUM));
++ mtk_hsdma_write(hsdma, HSDMA_REG_RX_CNT, HSDMA_DESCS_NUM);
++ /* reset */
++ mtk_hsdma_reset_chan(hsdma, chan);
++
++ /* enable rx intr */
++ mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, HSDMA_INT_RX_Q0);
++
++ /* enable dma */
++ mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, HSDMA_GLO_DEFAULT);
++
++ /* hardware info */
++ reg = mtk_hsdma_read(hsdma, HSDMA_REG_INFO);
++ dev_info(hsdma->ddev.dev, "rx: %d, tx: %d\n",
++ (reg >> HSDMA_INFO_RX_SHIFT) & HSDMA_INFO_RX_MASK,
++ (reg >> HSDMA_INFO_TX_SHIFT) & HSDMA_INFO_TX_MASK);
++
++ hsdma_dump_reg(hsdma);
++
++ return ret;
++}
++
++static void mtk_hsdma_uninit(struct mtk_hsdam_engine *hsdma)
++{
++ struct mtk_hsdma_chan *chan;
++
++ /* disable dma */
++ mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, 0);
++
++ /* disable intr */
++ mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, 0);
++
++ /* free desc */
++ chan = &hsdma->chan[0];
++ mtk_hsdam_free_desc(hsdma, chan);
++
++ /* tx */
++ mtk_hsdma_write(hsdma, HSDMA_REG_TX_BASE, 0);
++ mtk_hsdma_write(hsdma, HSDMA_REG_TX_CNT, 0);
++ /* rx */
++ mtk_hsdma_write(hsdma, HSDMA_REG_RX_BASE, 0);
++ mtk_hsdma_write(hsdma, HSDMA_REG_RX_CNT, 0);
++ /* reset */
++ mtk_hsdma_reset_chan(hsdma, chan);
++}
++
++static const struct of_device_id mtk_hsdma_of_match[] = {
++ { .compatible = "mediatek,mt7621-hsdma" },
++ { },
++};
++
++static int mtk_hsdma_probe(struct platform_device *pdev)
++{
++ const struct of_device_id *match;
++ struct mtk_hsdma_chan *chan;
++ struct mtk_hsdam_engine *hsdma;
++ struct dma_device *dd;
++ struct resource *res;
++ int ret;
++ int irq;
++ void __iomem *base;
++
++ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
++ if (ret)
++ return ret;
++
++ match = of_match_device(mtk_hsdma_of_match, &pdev->dev);
++ if (!match)
++ return -EINVAL;
++
++ hsdma = devm_kzalloc(&pdev->dev, sizeof(*hsdma), GFP_KERNEL);
++ if (!hsdma) {
++ dev_err(&pdev->dev, "alloc dma device failed\n");
++ return -EINVAL;
++ }
++
++ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++ base = devm_ioremap_resource(&pdev->dev, res);
++ if (IS_ERR(base))
++ return PTR_ERR(base);
++ hsdma->base = base + HSDMA_BASE_OFFSET;
++ tasklet_init(&hsdma->task, mtk_hsdma_tasklet, (unsigned long)hsdma);
++
++ irq = platform_get_irq(pdev, 0);
++ if (irq < 0) {
++ dev_err(&pdev->dev, "failed to get irq\n");
++ return -EINVAL;
++ }
++ ret = devm_request_irq(&pdev->dev, irq, mtk_hsdma_irq,
++ 0, dev_name(&pdev->dev), hsdma);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to request irq\n");
++ return ret;
++ }
++
++ device_reset(&pdev->dev);
++
++ dd = &hsdma->ddev;
++ dma_cap_set(DMA_MEMCPY, dd->cap_mask);
++ dd->copy_align = HSDMA_ALIGN_SIZE;
++ dd->device_free_chan_resources = mtk_hsdma_free_chan_resources;
++ dd->device_prep_dma_memcpy = mtk_hsdma_prep_dma_memcpy;
++ dd->device_terminate_all = mtk_hsdma_terminate_all;
++ dd->device_tx_status = mtk_hsdma_tx_status;
++ dd->device_issue_pending = mtk_hsdma_issue_pending;
++ dd->dev = &pdev->dev;
++ dd->dev->dma_parms = &hsdma->dma_parms;
++ dma_set_max_seg_size(dd->dev, HSDMA_MAX_PLEN);
++ INIT_LIST_HEAD(&dd->channels);
++
++ chan = &hsdma->chan[0];
++ chan->id = 0;
++ chan->vchan.desc_free = mtk_hsdma_desc_free;
++ vchan_init(&chan->vchan, dd);
++
++ /* init hardware */
++ ret = mtk_hsdma_init(hsdma);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to alloc ring descs\n");
++ return ret;
++ }
++
++ ret = dma_async_device_register(dd);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to register dma device\n");
++ return ret;
++ }
++
++ ret = of_dma_controller_register(pdev->dev.of_node,
++ of_dma_xlate_by_chan_id, hsdma);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to register of dma controller\n");
++ goto err_unregister;
++ }
++
++ platform_set_drvdata(pdev, hsdma);
++
++ return 0;
++
++err_unregister:
++ dma_async_device_unregister(dd);
++ return ret;
++}
++
++static int mtk_hsdma_remove(struct platform_device *pdev)
++{
++ struct mtk_hsdam_engine *hsdma = platform_get_drvdata(pdev);
++
++ mtk_hsdma_uninit(hsdma);
++
++ of_dma_controller_free(pdev->dev.of_node);
++ dma_async_device_unregister(&hsdma->ddev);
++
++ return 0;
++}
++
++static struct platform_driver mtk_hsdma_driver = {
++ .probe = mtk_hsdma_probe,
++ .remove = mtk_hsdma_remove,
++ .driver = {
++ .name = "hsdma-mt7621",
++ .of_match_table = mtk_hsdma_of_match,
++ },
++};
++module_platform_driver(mtk_hsdma_driver);
++
++MODULE_AUTHOR("Michael Lee <igvtee@gmail.com>");
++MODULE_DESCRIPTION("MTK HSDMA driver");
++MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-14 04:06:19 +0000