diff options
Diffstat (limited to 'drivers/dma/pch_dma.c')
| -rw-r--r-- | drivers/dma/pch_dma.c | 957 |
1 files changed, 957 insertions, 0 deletions
diff --git a/drivers/dma/pch_dma.c b/drivers/dma/pch_dma.c new file mode 100644 index 000000000000..3533948b88ba --- /dev/null +++ b/drivers/dma/pch_dma.c @@ -0,0 +1,957 @@ +/* + * Topcliff PCH DMA controller driver + * Copyright (c) 2010 Intel Corporation + * + * 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/interrupt.h> +#include <linux/module.h> +#include <linux/pch_dma.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_STATUS_ERR(x) (0x1 << ((x) + 8)) + +#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 8 + +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 reserved1; + u32 dma_sts0; + u32 dma_sts1; + u32 reserved2; + u32 reserved3; + struct pch_dma_desc_regs desc[0]; +}; + +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_data_direction dir; + struct tasklet_struct tasklet; + unsigned long err_status; + + spinlock_t lock; + + dma_cookie_t completed_cookie; + 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[0]; +}; + +#define PCH_DMA_CTL0 0x00 +#define PCH_DMA_CTL1 0x04 +#define PCH_DMA_CTL2 0x08 +#define PCH_DMA_STS0 0x10 +#define PCH_DMA_STS1 0x14 + +#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; + + val = dma_readl(pd, CTL2); + + if (enable) + val |= 0x1 << chan->chan_id; + else + val &= ~(0x1 << chan->chan_id); + + 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; + + val = dma_readl(pd, CTL0); + + if (pd_chan->dir == DMA_TO_DEVICE) + 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)); + + dma_writel(pd, CTL0, 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; + + val = dma_readl(pd, CTL0); + + val &= ~(DMA_CTL0_MODE_MASK_BITS << + (DMA_CTL0_BITS_PER_CH * chan->chan_id)); + val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id); + + dma_writel(pd, CTL0, val); + + dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n", + chan->chan_id, val); +} + +static u32 pdc_get_status(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 bool pdc_is_idle(struct pch_dma_chan *pd_chan) +{ + if (pdc_get_status(pd_chan) == DMA_STATUS_IDLE) + return true; + else + return false; +} + +static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc) +{ + struct pch_dma *pd = to_pd(pd_chan->chan.device); + u32 val; + + if (!pdc_is_idle(pd_chan)) { + dev_err(chan2dev(&pd_chan->chan), + "BUG: Attempt to start non-idle channel\n"); + return; + } + + 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); + + 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)) + pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT); + else + pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG); + + val = dma_readl(pd, CTL2); + val |= 1 << (DMA_CTL2_START_SHIFT_BITS + pd_chan->chan.chan_id); + dma_writel(pd, CTL2, val); +} + +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 pdc_assign_cookie(struct pch_dma_chan *pd_chan, + struct pch_dma_desc *desc) +{ + dma_cookie_t cookie = pd_chan->chan.cookie; + + if (++cookie < 0) + cookie = 1; + + pd_chan->chan.cookie = cookie; + desc->txd.cookie = cookie; + + return cookie; +} + +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_bh(&pd_chan->lock); + cookie = pdc_assign_cookie(pd_chan, desc); + + 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_bh(&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, GFP_KERNEL, &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; + + spin_lock_bh(&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_bh(&pd_chan->lock); + dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i); + + if (!ret) { + ret = pdc_alloc_desc(&pd_chan->chan, GFP_NOIO); + if (ret) { + spin_lock_bh(&pd_chan->lock); + pd_chan->descs_allocated++; + spin_unlock_bh(&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_bh(&pd_chan->lock); + list_splice_init(&desc->tx_list, &pd_chan->free_list); + list_add(&desc->desc_node, &pd_chan->free_list); + spin_unlock_bh(&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_bh(&pd_chan->lock); + list_splice(&tmp_list, &pd_chan->free_list); + pd_chan->descs_allocated = i; + pd_chan->completed_cookie = chan->cookie = 1; + spin_unlock_bh(&pd_chan->lock); + + pdc_enable_irq(chan, 1); + pdc_set_dir(chan); + + 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_bh(&pd_chan->lock); + list_splice_init(&pd_chan->free_list, &tmp_list); + pd_chan->descs_allocated = 0; + spin_unlock_bh(&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) +{ + struct pch_dma_chan *pd_chan = to_pd_chan(chan); + dma_cookie_t last_used; + dma_cookie_t last_completed; + int ret; + + spin_lock_bh(&pd_chan->lock); + last_completed = pd_chan->completed_cookie; + last_used = chan->cookie; + spin_unlock_bh(&pd_chan->lock); + + ret = dma_async_is_complete(cookie, last_completed, last_used); + + dma_set_tx_state(txstate, last_completed, last_used, 0); + + return ret; +} + +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_bh(&pd_chan->lock); + pdc_advance_work(pd_chan); + spin_unlock_bh(&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_data_direction direction, unsigned long flags) +{ + 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_FROM_DEVICE) + reg = pd_slave->rx_reg; + else if (direction == DMA_TO_DEVICE) + reg = pd_slave->tx_reg; + else + return NULL; + + 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_phys(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_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, + unsigned long arg) +{ + struct pch_dma_chan *pd_chan = to_pd_chan(chan); + struct pch_dma_desc *desc, *_d; + LIST_HEAD(list); + + if (cmd != DMA_TERMINATE_ALL) + return -ENXIO; + + spin_lock_bh(&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_bh(&pd_chan->lock); + + + return 0; +} + +static void pdc_tasklet(unsigned long data) +{ + struct pch_dma_chan *pd_chan = (struct pch_dma_chan *)data; + + if (!pdc_is_idle(pd_chan)) { + dev_err(chan2dev(&pd_chan->chan), + "BUG: handle non-idle channel in tasklet\n"); + return; + } + + spin_lock_bh(&pd_chan->lock); + if (test_and_clear_bit(0, &pd_chan->err_status)) + pdc_handle_error(pd_chan); + else + pdc_advance_work(pd_chan); + spin_unlock_bh(&pd_chan->lock); +} + +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; + int i; + int ret = IRQ_NONE; + + sts0 = dma_readl(pd, STS0); + + 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 (sts0 & DMA_STATUS_IRQ(i)) { + if (sts0 & DMA_STATUS_ERR(i)) + set_bit(0, &pd_chan->err_status); + + tasklet_schedule(&pd_chan->tasklet); + ret = IRQ_HANDLED; + } + + } + + /* clear interrupt bits in status register */ + dma_writel(pd, STS0, sts0); + + return ret; +} + +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); + + 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); + + 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; +} + +static int __devinit 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(struct pch_dma)+ + sizeof(struct pch_dma_chan) * nr_channels, 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"); + 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; + pd->dma.chancnt = nr_channels; + + 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; + pd_chan->chan.cookie = 1; + pd_chan->chan.chan_id = i; + + pd_chan->membase = ®s->desc[i]; + + pd_chan->dir = (i % 2) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + + 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_control = pd_device_control; + + 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: + return err; +} + +static void __devexit 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); + + list_for_each_entry_safe(chan, _c, &pd->dma.channels, + device_node) { + pd_chan = to_pd_chan(chan); + + tasklet_disable(&pd_chan->tasklet); + tasklet_kill(&pd_chan->tasklet); + } + + pci_pool_destroy(pd->pool); + free_irq(pdev->irq, pd); + pci_iounmap(pdev, pd->membase); + pci_release_regions(pdev); + pci_disable_device(pdev); + kfree(pd); + } +} + +/* PCI Device ID of DMA device */ +#define PCI_DEVICE_ID_PCH_DMA_8CH 0x8810 +#define PCI_DEVICE_ID_PCH_DMA_4CH 0x8815 + +static const struct pci_device_id pch_dma_id_table[] = { + { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_DMA_8CH), 8 }, + { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_DMA_4CH), 4 }, +}; + +static struct pci_driver pch_dma_driver = { + .name = DRV_NAME, + .id_table = pch_dma_id_table, + .probe = pch_dma_probe, + .remove = __devexit_p(pch_dma_remove), +#ifdef CONFIG_PM + .suspend = pch_dma_suspend, + .resume = pch_dma_resume, +#endif +}; + +static int __init pch_dma_init(void) +{ + return pci_register_driver(&pch_dma_driver); +} + +static void __exit pch_dma_exit(void) +{ + pci_unregister_driver(&pch_dma_driver); +} + +module_init(pch_dma_init); +module_exit(pch_dma_exit); + +MODULE_DESCRIPTION("Topcliff PCH DMA controller driver"); +MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>"); +MODULE_LICENSE("GPL v2"); |