--- /dev/null
+/*
+ * Topcliff PCH DMA controller driver
+ * Copyright (c) 2010 Intel Corporation
+ * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pch_dma.h>
+
+#include "dmaengine.h"
+
+#define DRV_NAME "pch-dma"
+
+#define DMA_CTL0_DISABLE 0x0
+#define DMA_CTL0_SG 0x1
+#define DMA_CTL0_ONESHOT 0x2
+#define DMA_CTL0_MODE_MASK_BITS 0x3
+#define DMA_CTL0_DIR_SHIFT_BITS 2
+#define DMA_CTL0_BITS_PER_CH 4
+
+#define DMA_CTL2_START_SHIFT_BITS 8
+#define DMA_CTL2_IRQ_ENABLE_MASK ((1UL << DMA_CTL2_START_SHIFT_BITS) - 1)
+
+#define DMA_STATUS_IDLE 0x0
+#define DMA_STATUS_DESC_READ 0x1
+#define DMA_STATUS_WAIT 0x2
+#define DMA_STATUS_ACCESS 0x3
+#define DMA_STATUS_BITS_PER_CH 2
+#define DMA_STATUS_MASK_BITS 0x3
+#define DMA_STATUS_SHIFT_BITS 16
+#define DMA_STATUS_IRQ(x) (0x1 << (x))
+#define DMA_STATUS0_ERR(x) (0x1 << ((x) + 8))
+#define DMA_STATUS2_ERR(x) (0x1 << (x))
+
+#define DMA_DESC_WIDTH_SHIFT_BITS 12
+#define DMA_DESC_WIDTH_1_BYTE (0x3 << DMA_DESC_WIDTH_SHIFT_BITS)
+#define DMA_DESC_WIDTH_2_BYTES (0x2 << DMA_DESC_WIDTH_SHIFT_BITS)
+#define DMA_DESC_WIDTH_4_BYTES (0x0 << DMA_DESC_WIDTH_SHIFT_BITS)
+#define DMA_DESC_MAX_COUNT_1_BYTE 0x3FF
+#define DMA_DESC_MAX_COUNT_2_BYTES 0x3FF
+#define DMA_DESC_MAX_COUNT_4_BYTES 0x7FF
+#define DMA_DESC_END_WITHOUT_IRQ 0x0
+#define DMA_DESC_END_WITH_IRQ 0x1
+#define DMA_DESC_FOLLOW_WITHOUT_IRQ 0x2
+#define DMA_DESC_FOLLOW_WITH_IRQ 0x3
+
+#define MAX_CHAN_NR 12
+
+#define DMA_MASK_CTL0_MODE 0x33333333
+#define DMA_MASK_CTL2_MODE 0x00003333
+
+static unsigned int init_nr_desc_per_channel = 64;
+module_param(init_nr_desc_per_channel, uint, 0644);
+MODULE_PARM_DESC(init_nr_desc_per_channel,
+ "initial descriptors per channel (default: 64)");
+
+struct pch_dma_desc_regs {
+ u32 dev_addr;
+ u32 mem_addr;
+ u32 size;
+ u32 next;
+};
+
+struct pch_dma_regs {
+ u32 dma_ctl0;
+ u32 dma_ctl1;
+ u32 dma_ctl2;
+ u32 dma_ctl3;
+ u32 dma_sts0;
+ u32 dma_sts1;
+ u32 dma_sts2;
+ u32 reserved3;
+ struct pch_dma_desc_regs desc[MAX_CHAN_NR];
+};
+
+struct pch_dma_desc {
+ struct pch_dma_desc_regs regs;
+ struct dma_async_tx_descriptor txd;
+ struct list_head desc_node;
+ struct list_head tx_list;
+};
+
+struct pch_dma_chan {
+ struct dma_chan chan;
+ void __iomem *membase;
+ enum dma_transfer_direction dir;
+ struct tasklet_struct tasklet;
+ unsigned long err_status;
+
+ spinlock_t lock;
+
+ struct list_head active_list;
+ struct list_head queue;
+ struct list_head free_list;
+ unsigned int descs_allocated;
+};
+
+#define PDC_DEV_ADDR 0x00
+#define PDC_MEM_ADDR 0x04
+#define PDC_SIZE 0x08
+#define PDC_NEXT 0x0C
+
+#define channel_readl(pdc, name) \
+ readl((pdc)->membase + PDC_##name)
+#define channel_writel(pdc, name, val) \
+ writel((val), (pdc)->membase + PDC_##name)
+
+struct pch_dma {
+ struct dma_device dma;
+ void __iomem *membase;
+ struct pci_pool *pool;
+ struct pch_dma_regs regs;
+ struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR];
+ struct pch_dma_chan channels[MAX_CHAN_NR];
+};
+
+#define PCH_DMA_CTL0 0x00
+#define PCH_DMA_CTL1 0x04
+#define PCH_DMA_CTL2 0x08
+#define PCH_DMA_CTL3 0x0C
+#define PCH_DMA_STS0 0x10
+#define PCH_DMA_STS1 0x14
+#define PCH_DMA_STS2 0x18
+
+#define dma_readl(pd, name) \
+ readl((pd)->membase + PCH_DMA_##name)
+#define dma_writel(pd, name, val) \
+ writel((val), (pd)->membase + PCH_DMA_##name)
+
+static inline
+struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd)
+{
+ return container_of(txd, struct pch_dma_desc, txd);
+}
+
+static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan)
+{
+ return container_of(chan, struct pch_dma_chan, chan);
+}
+
+static inline struct pch_dma *to_pd(struct dma_device *ddev)
+{
+ return container_of(ddev, struct pch_dma, dma);
+}
+
+static inline struct device *chan2dev(struct dma_chan *chan)
+{
+ return &chan->dev->device;
+}
+
+static inline struct device *chan2parent(struct dma_chan *chan)
+{
+ return chan->dev->device.parent;
+}
+
+static inline
+struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan)
+{
+ return list_first_entry(&pd_chan->active_list,
+ struct pch_dma_desc, desc_node);
+}
+
+static inline
+struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan)
+{
+ return list_first_entry(&pd_chan->queue,
+ struct pch_dma_desc, desc_node);
+}
+
+static void pdc_enable_irq(struct dma_chan *chan, int enable)
+{
+ struct pch_dma *pd = to_pd(chan->device);
+ u32 val;
+ int pos;
+
+ if (chan->chan_id < 8)
+ pos = chan->chan_id;
+ else
+ pos = chan->chan_id + 8;
+
+ val = dma_readl(pd, CTL2);
+
+ if (enable)
+ val |= 0x1 << pos;
+ else
+ val &= ~(0x1 << pos);
+
+ dma_writel(pd, CTL2, val);
+
+ dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n",
+ chan->chan_id, val);
+}
+
+static void pdc_set_dir(struct dma_chan *chan)
+{
+ struct pch_dma_chan *pd_chan = to_pd_chan(chan);
+ struct pch_dma *pd = to_pd(chan->device);
+ u32 val;
+ u32 mask_mode;
+ u32 mask_ctl;
+
+ if (chan->chan_id < 8) {
+ val = dma_readl(pd, CTL0);
+
+ mask_mode = DMA_CTL0_MODE_MASK_BITS <<
+ (DMA_CTL0_BITS_PER_CH * chan->chan_id);
+ mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
+ (DMA_CTL0_BITS_PER_CH * chan->chan_id));
+ val &= mask_mode;
+ if (pd_chan->dir == DMA_MEM_TO_DEV)
+ val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
+ DMA_CTL0_DIR_SHIFT_BITS);
+ else
+ val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
+ DMA_CTL0_DIR_SHIFT_BITS));
+
+ val |= mask_ctl;
+ dma_writel(pd, CTL0, val);
+ } else {
+ int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
+ val = dma_readl(pd, CTL3);
+
+ mask_mode = DMA_CTL0_MODE_MASK_BITS <<
+ (DMA_CTL0_BITS_PER_CH * ch);
+ mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
+ (DMA_CTL0_BITS_PER_CH * ch));
+ val &= mask_mode;
+ if (pd_chan->dir == DMA_MEM_TO_DEV)
+ val |= 0x1 << (DMA_CTL0_BITS_PER_CH * ch +
+ DMA_CTL0_DIR_SHIFT_BITS);
+ else
+ val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * ch +
+ DMA_CTL0_DIR_SHIFT_BITS));
+ val |= mask_ctl;
+ dma_writel(pd, CTL3, val);
+ }
+
+ dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n",
+ chan->chan_id, val);
+}
+
+static void pdc_set_mode(struct dma_chan *chan, u32 mode)
+{
+ struct pch_dma *pd = to_pd(chan->device);
+ u32 val;
+ u32 mask_ctl;
+ u32 mask_dir;
+
+ if (chan->chan_id < 8) {
+ mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
+ (DMA_CTL0_BITS_PER_CH * chan->chan_id));
+ mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +\
+ DMA_CTL0_DIR_SHIFT_BITS);
+ val = dma_readl(pd, CTL0);
+ val &= mask_dir;
+ val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id);
+ val |= mask_ctl;
+ dma_writel(pd, CTL0, val);
+ } else {
+ int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
+ mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
+ (DMA_CTL0_BITS_PER_CH * ch));
+ mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * ch +\
+ DMA_CTL0_DIR_SHIFT_BITS);
+ val = dma_readl(pd, CTL3);
+ val &= mask_dir;
+ val |= mode << (DMA_CTL0_BITS_PER_CH * ch);
+ val |= mask_ctl;
+ dma_writel(pd, CTL3, val);
+ }
+
+ dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n",
+ chan->chan_id, val);
+}
+
+static u32 pdc_get_status0(struct pch_dma_chan *pd_chan)
+{
+ struct pch_dma *pd = to_pd(pd_chan->chan.device);
+ u32 val;
+
+ val = dma_readl(pd, STS0);
+ return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
+ DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id));
+}
+
+static u32 pdc_get_status2(struct pch_dma_chan *pd_chan)
+{
+ struct pch_dma *pd = to_pd(pd_chan->chan.device);
+ u32 val;
+
+ val = dma_readl(pd, STS2);
+ return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
+ DMA_STATUS_BITS_PER_CH * (pd_chan->chan.chan_id - 8)));
+}
+
+static bool pdc_is_idle(struct pch_dma_chan *pd_chan)
+{
+ u32 sts;
+
+ if (pd_chan->chan.chan_id < 8)
+ sts = pdc_get_status0(pd_chan);
+ else
+ sts = pdc_get_status2(pd_chan);
+
+
+ if (sts == DMA_STATUS_IDLE)
+ return true;
+ else
+ return false;
+}
+
+static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
+{
+ if (!pdc_is_idle(pd_chan)) {
+ dev_err(chan2dev(&pd_chan->chan),
+ "BUG: Attempt to start non-idle channel\n");
+ return;
+ }
+
+ dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",
+ pd_chan->chan.chan_id, desc->regs.dev_addr);
+ dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",
+ pd_chan->chan.chan_id, desc->regs.mem_addr);
+ dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n",
+ pd_chan->chan.chan_id, desc->regs.size);
+ dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",
+ pd_chan->chan.chan_id, desc->regs.next);
+
+ if (list_empty(&desc->tx_list)) {
+ channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
+ channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
+ channel_writel(pd_chan, SIZE, desc->regs.size);
+ channel_writel(pd_chan, NEXT, desc->regs.next);
+ pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);
+ } else {
+ channel_writel(pd_chan, NEXT, desc->txd.phys);
+ pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);
+ }
+}
+
+static void pdc_chain_complete(struct pch_dma_chan *pd_chan,
+ struct pch_dma_desc *desc)
+{
+ struct dma_async_tx_descriptor *txd = &desc->txd;
+ dma_async_tx_callback callback = txd->callback;
+ void *param = txd->callback_param;
+
+ list_splice_init(&desc->tx_list, &pd_chan->free_list);
+ list_move(&desc->desc_node, &pd_chan->free_list);
+
+ if (callback)
+ callback(param);
+}
+
+static void pdc_complete_all(struct pch_dma_chan *pd_chan)
+{
+ struct pch_dma_desc *desc, *_d;
+ LIST_HEAD(list);
+
+ BUG_ON(!pdc_is_idle(pd_chan));
+
+ if (!list_empty(&pd_chan->queue))
+ pdc_dostart(pd_chan, pdc_first_queued(pd_chan));
+
+ list_splice_init(&pd_chan->active_list, &list);
+ list_splice_init(&pd_chan->queue, &pd_chan->active_list);
+
+ list_for_each_entry_safe(desc, _d, &list, desc_node)
+ pdc_chain_complete(pd_chan, desc);
+}
+
+static void pdc_handle_error(struct pch_dma_chan *pd_chan)
+{
+ struct pch_dma_desc *bad_desc;
+
+ bad_desc = pdc_first_active(pd_chan);
+ list_del(&bad_desc->desc_node);
+
+ list_splice_init(&pd_chan->queue, pd_chan->active_list.prev);
+
+ if (!list_empty(&pd_chan->active_list))
+ pdc_dostart(pd_chan, pdc_first_active(pd_chan));
+
+ dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n");
+ dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n",
+ bad_desc->txd.cookie);
+
+ pdc_chain_complete(pd_chan, bad_desc);
+}
+
+static void pdc_advance_work(struct pch_dma_chan *pd_chan)
+{
+ if (list_empty(&pd_chan->active_list) ||
+ list_is_singular(&pd_chan->active_list)) {
+ pdc_complete_all(pd_chan);
+ } else {
+ pdc_chain_complete(pd_chan, pdc_first_active(pd_chan));
+ pdc_dostart(pd_chan, pdc_first_active(pd_chan));
+ }
+}
+
+static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
+{
+ struct pch_dma_desc *desc = to_pd_desc(txd);
+ struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan);
+ dma_cookie_t cookie;
+
+ spin_lock(&pd_chan->lock);
+ cookie = dma_cookie_assign(txd);
+
+ if (list_empty(&pd_chan->active_list)) {
+ list_add_tail(&desc->desc_node, &pd_chan->active_list);
+ pdc_dostart(pd_chan, desc);
+ } else {
+ list_add_tail(&desc->desc_node, &pd_chan->queue);
+ }
+
+ spin_unlock(&pd_chan->lock);
+ return 0;
+}
+
+static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags)
+{
+ struct pch_dma_desc *desc = NULL;
+ struct pch_dma *pd = to_pd(chan->device);
+ dma_addr_t addr;
+
+ desc = pci_pool_alloc(pd->pool, flags, &addr);
+ if (desc) {
+ memset(desc, 0, sizeof(struct pch_dma_desc));
+ INIT_LIST_HEAD(&desc->tx_list);
+ dma_async_tx_descriptor_init(&desc->txd, chan);
+ desc->txd.tx_submit = pd_tx_submit;
+ desc->txd.flags = DMA_CTRL_ACK;
+ desc->txd.phys = addr;
+ }
+
+ return desc;
+}
+
+static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan)
+{
+ struct pch_dma_desc *desc, *_d;
+ struct pch_dma_desc *ret = NULL;
+ int i = 0;
+
+ spin_lock(&pd_chan->lock);
+ list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) {
+ i++;
+ if (async_tx_test_ack(&desc->txd)) {
+ list_del(&desc->desc_node);
+ ret = desc;
+ break;
+ }
+ dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc);
+ }
+ spin_unlock(&pd_chan->lock);
+ dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i);
+
+ if (!ret) {
+ ret = pdc_alloc_desc(&pd_chan->chan, GFP_ATOMIC);
+ if (ret) {
+ spin_lock(&pd_chan->lock);
+ pd_chan->descs_allocated++;
+ spin_unlock(&pd_chan->lock);
+ } else {
+ dev_err(chan2dev(&pd_chan->chan),
+ "failed to alloc desc\n");
+ }
+ }
+
+ return ret;
+}
+
+static void pdc_desc_put(struct pch_dma_chan *pd_chan,
+ struct pch_dma_desc *desc)
+{
+ if (desc) {
+ spin_lock(&pd_chan->lock);
+ list_splice_init(&desc->tx_list, &pd_chan->free_list);
+ list_add(&desc->desc_node, &pd_chan->free_list);
+ spin_unlock(&pd_chan->lock);
+ }
+}
+
+static int pd_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct pch_dma_chan *pd_chan = to_pd_chan(chan);
+ struct pch_dma_desc *desc;
+ LIST_HEAD(tmp_list);
+ int i;
+
+ if (!pdc_is_idle(pd_chan)) {
+ dev_dbg(chan2dev(chan), "DMA channel not idle ?\n");
+ return -EIO;
+ }
+
+ if (!list_empty(&pd_chan->free_list))
+ return pd_chan->descs_allocated;
+
+ for (i = 0; i < init_nr_desc_per_channel; i++) {
+ desc = pdc_alloc_desc(chan, GFP_KERNEL);
+
+ if (!desc) {
+ dev_warn(chan2dev(chan),
+ "Only allocated %d initial descriptors\n", i);
+ break;
+ }
+
+ list_add_tail(&desc->desc_node, &tmp_list);
+ }
+
+ spin_lock_irq(&pd_chan->lock);
+ list_splice(&tmp_list, &pd_chan->free_list);
+ pd_chan->descs_allocated = i;
+ dma_cookie_init(chan);
+ spin_unlock_irq(&pd_chan->lock);
+
+ pdc_enable_irq(chan, 1);
+
+ return pd_chan->descs_allocated;
+}
+
+static void pd_free_chan_resources(struct dma_chan *chan)
+{
+ struct pch_dma_chan *pd_chan = to_pd_chan(chan);
+ struct pch_dma *pd = to_pd(chan->device);
+ struct pch_dma_desc *desc, *_d;
+ LIST_HEAD(tmp_list);
+
+ BUG_ON(!pdc_is_idle(pd_chan));
+ BUG_ON(!list_empty(&pd_chan->active_list));
+ BUG_ON(!list_empty(&pd_chan->queue));
+
+ spin_lock_irq(&pd_chan->lock);
+ list_splice_init(&pd_chan->free_list, &tmp_list);
+ pd_chan->descs_allocated = 0;
+ spin_unlock_irq(&pd_chan->lock);
+
+ list_for_each_entry_safe(desc, _d, &tmp_list, desc_node)
+ pci_pool_free(pd->pool, desc, desc->txd.phys);
+
+ pdc_enable_irq(chan, 0);
+}
+
+static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ return dma_cookie_status(chan, cookie, txstate);
+}
+
+static void pd_issue_pending(struct dma_chan *chan)
+{
+ struct pch_dma_chan *pd_chan = to_pd_chan(chan);
+
+ if (pdc_is_idle(pd_chan)) {
+ spin_lock(&pd_chan->lock);
+ pdc_advance_work(pd_chan);
+ spin_unlock(&pd_chan->lock);
+ }
+}
+
+static struct dma_async_tx_descriptor *pd_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 pch_dma_chan *pd_chan = to_pd_chan(chan);
+ struct pch_dma_slave *pd_slave = chan->private;
+ struct pch_dma_desc *first = NULL;
+ struct pch_dma_desc *prev = NULL;
+ struct pch_dma_desc *desc = NULL;
+ struct scatterlist *sg;
+ dma_addr_t reg;
+ int i;
+
+ if (unlikely(!sg_len)) {
+ dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n");
+ return NULL;
+ }
+
+ if (direction == DMA_DEV_TO_MEM)
+ reg = pd_slave->rx_reg;
+ else if (direction == DMA_MEM_TO_DEV)
+ reg = pd_slave->tx_reg;
+ else
+ return NULL;
+
+ pd_chan->dir = direction;
+ pdc_set_dir(chan);
+
+ for_each_sg(sgl, sg, sg_len, i) {
+ desc = pdc_desc_get(pd_chan);
+
+ if (!desc)
+ goto err_desc_get;
+
+ desc->regs.dev_addr = reg;
+ desc->regs.mem_addr = sg_dma_address(sg);
+ desc->regs.size = sg_dma_len(sg);
+ desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ;
+
+ switch (pd_slave->width) {
+ case PCH_DMA_WIDTH_1_BYTE:
+ if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE)
+ goto err_desc_get;
+ desc->regs.size |= DMA_DESC_WIDTH_1_BYTE;
+ break;
+ case PCH_DMA_WIDTH_2_BYTES:
+ if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES)
+ goto err_desc_get;
+ desc->regs.size |= DMA_DESC_WIDTH_2_BYTES;
+ break;
+ case PCH_DMA_WIDTH_4_BYTES:
+ if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES)
+ goto err_desc_get;
+ desc->regs.size |= DMA_DESC_WIDTH_4_BYTES;
+ break;
+ default:
+ goto err_desc_get;
+ }
+
+ if (!first) {
+ first = desc;
+ } else {
+ prev->regs.next |= desc->txd.phys;
+ list_add_tail(&desc->desc_node, &first->tx_list);
+ }
+
+ prev = desc;
+ }
+
+ if (flags & DMA_PREP_INTERRUPT)
+ desc->regs.next = DMA_DESC_END_WITH_IRQ;
+ else
+ desc->regs.next = DMA_DESC_END_WITHOUT_IRQ;
+
+ first->txd.cookie = -EBUSY;
+ desc->txd.flags = flags;
+
+ return &first->txd;
+
+err_desc_get:
+ dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n");
+ pdc_desc_put(pd_chan, first);
+ return NULL;
+}
+
+static int pd_device_terminate_all(struct dma_chan *chan)
+{
+ struct pch_dma_chan *pd_chan = to_pd_chan(chan);
+ struct pch_dma_desc *desc, *_d;
+ LIST_HEAD(list);
+
+ spin_lock_irq(&pd_chan->lock);
+
+ pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE);
+
+ list_splice_init(&pd_chan->active_list, &list);
+ list_splice_init(&pd_chan->queue, &list);
+
+ list_for_each_entry_safe(desc, _d, &list, desc_node)
+ pdc_chain_complete(pd_chan, desc);
+
+ spin_unlock_irq(&pd_chan->lock);
+
+ return 0;
+}
+
+static void pdc_tasklet(unsigned long data)
+{
+ struct pch_dma_chan *pd_chan = (struct pch_dma_chan *)data;
+ unsigned long flags;
+
+ if (!pdc_is_idle(pd_chan)) {
+ dev_err(chan2dev(&pd_chan->chan),
+ "BUG: handle non-idle channel in tasklet\n");
+ return;
+ }
+
+ spin_lock_irqsave(&pd_chan->lock, flags);
+ if (test_and_clear_bit(0, &pd_chan->err_status))
+ pdc_handle_error(pd_chan);
+ else
+ pdc_advance_work(pd_chan);
+ spin_unlock_irqrestore(&pd_chan->lock, flags);
+}
+
+static irqreturn_t pd_irq(int irq, void *devid)
+{
+ struct pch_dma *pd = (struct pch_dma *)devid;
+ struct pch_dma_chan *pd_chan;
+ u32 sts0;
+ u32 sts2;
+ int i;
+ int ret0 = IRQ_NONE;
+ int ret2 = IRQ_NONE;
+
+ sts0 = dma_readl(pd, STS0);
+ sts2 = dma_readl(pd, STS2);
+
+ dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0);
+
+ for (i = 0; i < pd->dma.chancnt; i++) {
+ pd_chan = &pd->channels[i];
+
+ if (i < 8) {
+ if (sts0 & DMA_STATUS_IRQ(i)) {
+ if (sts0 & DMA_STATUS0_ERR(i))
+ set_bit(0, &pd_chan->err_status);
+
+ tasklet_schedule(&pd_chan->tasklet);
+ ret0 = IRQ_HANDLED;
+ }
+ } else {
+ if (sts2 & DMA_STATUS_IRQ(i - 8)) {
+ if (sts2 & DMA_STATUS2_ERR(i))
+ set_bit(0, &pd_chan->err_status);
+
+ tasklet_schedule(&pd_chan->tasklet);
+ ret2 = IRQ_HANDLED;
+ }
+ }
+ }
+
+ /* clear interrupt bits in status register */
+ if (ret0)
+ dma_writel(pd, STS0, sts0);
+ if (ret2)
+ dma_writel(pd, STS2, sts2);
+
+ return ret0 | ret2;
+}
+
+#ifdef CONFIG_PM
+static void pch_dma_save_regs(struct pch_dma *pd)
+{
+ struct pch_dma_chan *pd_chan;
+ struct dma_chan *chan, *_c;
+ int i = 0;
+
+ pd->regs.dma_ctl0 = dma_readl(pd, CTL0);
+ pd->regs.dma_ctl1 = dma_readl(pd, CTL1);
+ pd->regs.dma_ctl2 = dma_readl(pd, CTL2);
+ pd->regs.dma_ctl3 = dma_readl(pd, CTL3);
+
+ list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
+ pd_chan = to_pd_chan(chan);
+
+ pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);
+ pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);
+ pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);
+ pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);
+
+ i++;
+ }
+}
+
+static void pch_dma_restore_regs(struct pch_dma *pd)
+{
+ struct pch_dma_chan *pd_chan;
+ struct dma_chan *chan, *_c;
+ int i = 0;
+
+ dma_writel(pd, CTL0, pd->regs.dma_ctl0);
+ dma_writel(pd, CTL1, pd->regs.dma_ctl1);
+ dma_writel(pd, CTL2, pd->regs.dma_ctl2);
+ dma_writel(pd, CTL3, pd->regs.dma_ctl3);
+
+ list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
+ pd_chan = to_pd_chan(chan);
+
+ channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr);
+ channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr);
+ channel_writel(pd_chan, SIZE, pd->ch_regs[i].size);
+ channel_writel(pd_chan, NEXT, pd->ch_regs[i].next);
+
+ i++;
+ }
+}
+
+static int pch_dma_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+ struct pch_dma *pd = pci_get_drvdata(pdev);
+
+ if (pd)
+ pch_dma_save_regs(pd);
+
+ pci_save_state(pdev);
+ pci_disable_device(pdev);
+ pci_set_power_state(pdev, pci_choose_state(pdev, state));
+
+ return 0;
+}
+
+static int pch_dma_resume(struct pci_dev *pdev)
+{
+ struct pch_dma *pd = pci_get_drvdata(pdev);
+ int err;
+
+ pci_set_power_state(pdev, PCI_D0);
+ pci_restore_state(pdev);
+
+ err = pci_enable_device(pdev);
+ if (err) {
+ dev_dbg(&pdev->dev, "failed to enable device\n");
+ return err;
+ }
+
+ if (pd)
+ pch_dma_restore_regs(pd);
+
+ return 0;
+}
+#endif
+
+static int pch_dma_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct pch_dma *pd;
+ struct pch_dma_regs *regs;
+ unsigned int nr_channels;
+ int err;
+ int i;
+
+ nr_channels = id->driver_data;
+ pd = kzalloc(sizeof(*pd), GFP_KERNEL);
+ if (!pd)
+ return -ENOMEM;
+
+ pci_set_drvdata(pdev, pd);
+
+ err = pci_enable_device(pdev);
+ if (err) {
+ dev_err(&pdev->dev, "Cannot enable PCI device\n");
+ goto err_free_mem;
+ }
+
+ if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) {
+ dev_err(&pdev->dev, "Cannot find proper base address\n");
+ err = -ENODEV;
+ goto err_disable_pdev;
+ }
+
+ err = pci_request_regions(pdev, DRV_NAME);
+ if (err) {
+ dev_err(&pdev->dev, "Cannot obtain PCI resources\n");
+ goto err_disable_pdev;
+ }
+
+ err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (err) {
+ dev_err(&pdev->dev, "Cannot set proper DMA config\n");
+ goto err_free_res;
+ }
+
+ regs = pd->membase = pci_iomap(pdev, 1, 0);
+ if (!pd->membase) {
+ dev_err(&pdev->dev, "Cannot map MMIO registers\n");
+ err = -ENOMEM;
+ goto err_free_res;
+ }
+
+ pci_set_master(pdev);
+
+ err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to request IRQ\n");
+ goto err_iounmap;
+ }
+
+ pd->pool = pci_pool_create("pch_dma_desc_pool", pdev,
+ sizeof(struct pch_dma_desc), 4, 0);
+ if (!pd->pool) {
+ dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n");
+ err = -ENOMEM;
+ goto err_free_irq;
+ }
+
+ pd->dma.dev = &pdev->dev;
+
+ INIT_LIST_HEAD(&pd->dma.channels);
+
+ for (i = 0; i < nr_channels; i++) {
+ struct pch_dma_chan *pd_chan = &pd->channels[i];
+
+ pd_chan->chan.device = &pd->dma;
+ dma_cookie_init(&pd_chan->chan);
+
+ pd_chan->membase = ®s->desc[i];
+
+ spin_lock_init(&pd_chan->lock);
+
+ INIT_LIST_HEAD(&pd_chan->active_list);
+ INIT_LIST_HEAD(&pd_chan->queue);
+ INIT_LIST_HEAD(&pd_chan->free_list);
+
+ tasklet_init(&pd_chan->tasklet, pdc_tasklet,
+ (unsigned long)pd_chan);
+ list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels);
+ }
+
+ dma_cap_zero(pd->dma.cap_mask);
+ dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask);
+ dma_cap_set(DMA_SLAVE, pd->dma.cap_mask);
+
+ pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources;
+ pd->dma.device_free_chan_resources = pd_free_chan_resources;
+ pd->dma.device_tx_status = pd_tx_status;
+ pd->dma.device_issue_pending = pd_issue_pending;
+ pd->dma.device_prep_slave_sg = pd_prep_slave_sg;
+ pd->dma.device_terminate_all = pd_device_terminate_all;
+
+ err = dma_async_device_register(&pd->dma);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to register DMA device\n");
+ goto err_free_pool;
+ }
+
+ return 0;
+
+err_free_pool:
+ pci_pool_destroy(pd->pool);
+err_free_irq:
+ free_irq(pdev->irq, pd);
+err_iounmap:
+ pci_iounmap(pdev, pd->membase);
+err_free_res:
+ pci_release_regions(pdev);
+err_disable_pdev:
+ pci_disable_device(pdev);
+err_free_mem:
+ kfree(pd);
+ return err;
+}
+
+static void pch_dma_remove(struct pci_dev *pdev)
+{
+ struct pch_dma *pd = pci_get_drvdata(pdev);
+ struct pch_dma_chan *pd_chan;
+ struct dma_chan *chan, *_c;
+
+ if (pd) {
+ dma_async_device_unregister(&pd->dma);
+
+ free_irq(pdev->irq, pd);
+
+ list_for_each_entry_safe(chan, _c, &pd->dma.channels,
+ device_node) {
+ pd_chan = to_pd_chan(chan);
+
+ tasklet_kill(&pd_chan->tasklet);
+ }
+
+ pci_pool_destroy(pd->pool);
+ pci_iounmap(pdev, pd->membase);
+ pci_release_regions(pdev);
+ pci_disable_device(pdev);
+ kfree(pd);
+ }
+}
+
+/* PCI Device ID of DMA device */
+#define PCI_VENDOR_ID_ROHM 0x10DB
+#define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH 0x8810
+#define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH 0x8815
+#define PCI_DEVICE_ID_ML7213_DMA1_8CH 0x8026
+#define PCI_DEVICE_ID_ML7213_DMA2_8CH 0x802B
+#define PCI_DEVICE_ID_ML7213_DMA3_4CH 0x8034
+#define PCI_DEVICE_ID_ML7213_DMA4_12CH 0x8032
+#define PCI_DEVICE_ID_ML7223_DMA1_4CH 0x800B
+#define PCI_DEVICE_ID_ML7223_DMA2_4CH 0x800E
+#define PCI_DEVICE_ID_ML7223_DMA3_4CH 0x8017
+#define PCI_DEVICE_ID_ML7223_DMA4_4CH 0x803B
+#define PCI_DEVICE_ID_ML7831_DMA1_8CH 0x8810
+#define PCI_DEVICE_ID_ML7831_DMA2_4CH 0x8815
+
+static const struct pci_device_id pch_dma_id_table[] = {
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 },
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 },
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA4_12CH), 12}, /* I2S */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA1_4CH), 4}, /* UART */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA2_4CH), 4}, /* Video SPI */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA3_4CH), 4}, /* Security */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA4_4CH), 4}, /* FPGA */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA1_8CH), 8}, /* UART */
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA2_4CH), 4}, /* SPI */
+ { 0, },
+};
+
+static struct pci_driver pch_dma_driver = {
+ .name = DRV_NAME,
+ .id_table = pch_dma_id_table,
+ .probe = pch_dma_probe,
+ .remove = pch_dma_remove,
+#ifdef CONFIG_PM
+ .suspend = pch_dma_suspend,
+ .resume = pch_dma_resume,
+#endif
+};
+
+module_pci_driver(pch_dma_driver);
+
+MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH "
+ "DMA controller driver");
+MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(pci, pch_dma_id_table);
Code Review / kvmfornfv.git / blobdiff