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-rw-r--r--drivers/dma/mv_xor.c1468
1 files changed, 1468 insertions, 0 deletions
diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
new file mode 100644
index 000000000..23b232b57
--- /dev/null
+++ b/drivers/dma/mv_xor.c
@@ -0,0 +1,1468 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * offload engine driver for the Marvell XOR engine
+ * Copyright (C) 2007, 2008, Marvell International Ltd.
+ */
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/memory.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/cpumask.h>
+#include <linux/platform_data/dma-mv_xor.h>
+
+#include "dmaengine.h"
+#include "mv_xor.h"
+
+enum mv_xor_type {
+ XOR_ORION,
+ XOR_ARMADA_38X,
+ XOR_ARMADA_37XX,
+};
+
+enum mv_xor_mode {
+ XOR_MODE_IN_REG,
+ XOR_MODE_IN_DESC,
+};
+
+static void mv_xor_issue_pending(struct dma_chan *chan);
+
+#define to_mv_xor_chan(chan) \
+ container_of(chan, struct mv_xor_chan, dmachan)
+
+#define to_mv_xor_slot(tx) \
+ container_of(tx, struct mv_xor_desc_slot, async_tx)
+
+#define mv_chan_to_devp(chan) \
+ ((chan)->dmadev.dev)
+
+static void mv_desc_init(struct mv_xor_desc_slot *desc,
+ dma_addr_t addr, u32 byte_count,
+ enum dma_ctrl_flags flags)
+{
+ struct mv_xor_desc *hw_desc = desc->hw_desc;
+
+ hw_desc->status = XOR_DESC_DMA_OWNED;
+ hw_desc->phy_next_desc = 0;
+ /* Enable end-of-descriptor interrupts only for DMA_PREP_INTERRUPT */
+ hw_desc->desc_command = (flags & DMA_PREP_INTERRUPT) ?
+ XOR_DESC_EOD_INT_EN : 0;
+ hw_desc->phy_dest_addr = addr;
+ hw_desc->byte_count = byte_count;
+}
+
+static void mv_desc_set_mode(struct mv_xor_desc_slot *desc)
+{
+ struct mv_xor_desc *hw_desc = desc->hw_desc;
+
+ switch (desc->type) {
+ case DMA_XOR:
+ case DMA_INTERRUPT:
+ hw_desc->desc_command |= XOR_DESC_OPERATION_XOR;
+ break;
+ case DMA_MEMCPY:
+ hw_desc->desc_command |= XOR_DESC_OPERATION_MEMCPY;
+ break;
+ default:
+ BUG();
+ return;
+ }
+}
+
+static void mv_desc_set_next_desc(struct mv_xor_desc_slot *desc,
+ u32 next_desc_addr)
+{
+ struct mv_xor_desc *hw_desc = desc->hw_desc;
+ BUG_ON(hw_desc->phy_next_desc);
+ hw_desc->phy_next_desc = next_desc_addr;
+}
+
+static void mv_desc_set_src_addr(struct mv_xor_desc_slot *desc,
+ int index, dma_addr_t addr)
+{
+ struct mv_xor_desc *hw_desc = desc->hw_desc;
+ hw_desc->phy_src_addr[mv_phy_src_idx(index)] = addr;
+ if (desc->type == DMA_XOR)
+ hw_desc->desc_command |= (1 << index);
+}
+
+static u32 mv_chan_get_current_desc(struct mv_xor_chan *chan)
+{
+ return readl_relaxed(XOR_CURR_DESC(chan));
+}
+
+static void mv_chan_set_next_descriptor(struct mv_xor_chan *chan,
+ u32 next_desc_addr)
+{
+ writel_relaxed(next_desc_addr, XOR_NEXT_DESC(chan));
+}
+
+static void mv_chan_unmask_interrupts(struct mv_xor_chan *chan)
+{
+ u32 val = readl_relaxed(XOR_INTR_MASK(chan));
+ val |= XOR_INTR_MASK_VALUE << (chan->idx * 16);
+ writel_relaxed(val, XOR_INTR_MASK(chan));
+}
+
+static u32 mv_chan_get_intr_cause(struct mv_xor_chan *chan)
+{
+ u32 intr_cause = readl_relaxed(XOR_INTR_CAUSE(chan));
+ intr_cause = (intr_cause >> (chan->idx * 16)) & 0xFFFF;
+ return intr_cause;
+}
+
+static void mv_chan_clear_eoc_cause(struct mv_xor_chan *chan)
+{
+ u32 val;
+
+ val = XOR_INT_END_OF_DESC | XOR_INT_END_OF_CHAIN | XOR_INT_STOPPED;
+ val = ~(val << (chan->idx * 16));
+ dev_dbg(mv_chan_to_devp(chan), "%s, val 0x%08x\n", __func__, val);
+ writel_relaxed(val, XOR_INTR_CAUSE(chan));
+}
+
+static void mv_chan_clear_err_status(struct mv_xor_chan *chan)
+{
+ u32 val = 0xFFFF0000 >> (chan->idx * 16);
+ writel_relaxed(val, XOR_INTR_CAUSE(chan));
+}
+
+static void mv_chan_set_mode(struct mv_xor_chan *chan,
+ u32 op_mode)
+{
+ u32 config = readl_relaxed(XOR_CONFIG(chan));
+
+ config &= ~0x7;
+ config |= op_mode;
+
+#if defined(__BIG_ENDIAN)
+ config |= XOR_DESCRIPTOR_SWAP;
+#else
+ config &= ~XOR_DESCRIPTOR_SWAP;
+#endif
+
+ writel_relaxed(config, XOR_CONFIG(chan));
+}
+
+static void mv_chan_activate(struct mv_xor_chan *chan)
+{
+ dev_dbg(mv_chan_to_devp(chan), " activate chan.\n");
+
+ /* writel ensures all descriptors are flushed before activation */
+ writel(BIT(0), XOR_ACTIVATION(chan));
+}
+
+static char mv_chan_is_busy(struct mv_xor_chan *chan)
+{
+ u32 state = readl_relaxed(XOR_ACTIVATION(chan));
+
+ state = (state >> 4) & 0x3;
+
+ return (state == 1) ? 1 : 0;
+}
+
+/*
+ * mv_chan_start_new_chain - program the engine to operate on new
+ * chain headed by sw_desc
+ * Caller must hold &mv_chan->lock while calling this function
+ */
+static void mv_chan_start_new_chain(struct mv_xor_chan *mv_chan,
+ struct mv_xor_desc_slot *sw_desc)
+{
+ dev_dbg(mv_chan_to_devp(mv_chan), "%s %d: sw_desc %p\n",
+ __func__, __LINE__, sw_desc);
+
+ /* set the hardware chain */
+ mv_chan_set_next_descriptor(mv_chan, sw_desc->async_tx.phys);
+
+ mv_chan->pending++;
+ mv_xor_issue_pending(&mv_chan->dmachan);
+}
+
+static dma_cookie_t
+mv_desc_run_tx_complete_actions(struct mv_xor_desc_slot *desc,
+ struct mv_xor_chan *mv_chan,
+ dma_cookie_t cookie)
+{
+ BUG_ON(desc->async_tx.cookie < 0);
+
+ if (desc->async_tx.cookie > 0) {
+ cookie = desc->async_tx.cookie;
+
+ dma_descriptor_unmap(&desc->async_tx);
+ /* call the callback (must not sleep or submit new
+ * operations to this channel)
+ */
+ dmaengine_desc_get_callback_invoke(&desc->async_tx, NULL);
+ }
+
+ /* run dependent operations */
+ dma_run_dependencies(&desc->async_tx);
+
+ return cookie;
+}
+
+static int
+mv_chan_clean_completed_slots(struct mv_xor_chan *mv_chan)
+{
+ struct mv_xor_desc_slot *iter, *_iter;
+
+ dev_dbg(mv_chan_to_devp(mv_chan), "%s %d\n", __func__, __LINE__);
+ list_for_each_entry_safe(iter, _iter, &mv_chan->completed_slots,
+ node) {
+
+ if (async_tx_test_ack(&iter->async_tx)) {
+ list_move_tail(&iter->node, &mv_chan->free_slots);
+ if (!list_empty(&iter->sg_tx_list)) {
+ list_splice_tail_init(&iter->sg_tx_list,
+ &mv_chan->free_slots);
+ }
+ }
+ }
+ return 0;
+}
+
+static int
+mv_desc_clean_slot(struct mv_xor_desc_slot *desc,
+ struct mv_xor_chan *mv_chan)
+{
+ dev_dbg(mv_chan_to_devp(mv_chan), "%s %d: desc %p flags %d\n",
+ __func__, __LINE__, desc, desc->async_tx.flags);
+
+ /* the client is allowed to attach dependent operations
+ * until 'ack' is set
+ */
+ if (!async_tx_test_ack(&desc->async_tx)) {
+ /* move this slot to the completed_slots */
+ list_move_tail(&desc->node, &mv_chan->completed_slots);
+ if (!list_empty(&desc->sg_tx_list)) {
+ list_splice_tail_init(&desc->sg_tx_list,
+ &mv_chan->completed_slots);
+ }
+ } else {
+ list_move_tail(&desc->node, &mv_chan->free_slots);
+ if (!list_empty(&desc->sg_tx_list)) {
+ list_splice_tail_init(&desc->sg_tx_list,
+ &mv_chan->free_slots);
+ }
+ }
+
+ return 0;
+}
+
+/* This function must be called with the mv_xor_chan spinlock held */
+static void mv_chan_slot_cleanup(struct mv_xor_chan *mv_chan)
+{
+ struct mv_xor_desc_slot *iter, *_iter;
+ dma_cookie_t cookie = 0;
+ int busy = mv_chan_is_busy(mv_chan);
+ u32 current_desc = mv_chan_get_current_desc(mv_chan);
+ int current_cleaned = 0;
+ struct mv_xor_desc *hw_desc;
+
+ dev_dbg(mv_chan_to_devp(mv_chan), "%s %d\n", __func__, __LINE__);
+ dev_dbg(mv_chan_to_devp(mv_chan), "current_desc %x\n", current_desc);
+ mv_chan_clean_completed_slots(mv_chan);
+
+ /* free completed slots from the chain starting with
+ * the oldest descriptor
+ */
+
+ list_for_each_entry_safe(iter, _iter, &mv_chan->chain,
+ node) {
+
+ /* clean finished descriptors */
+ hw_desc = iter->hw_desc;
+ if (hw_desc->status & XOR_DESC_SUCCESS) {
+ cookie = mv_desc_run_tx_complete_actions(iter, mv_chan,
+ cookie);
+
+ /* done processing desc, clean slot */
+ mv_desc_clean_slot(iter, mv_chan);
+
+ /* break if we did cleaned the current */
+ if (iter->async_tx.phys == current_desc) {
+ current_cleaned = 1;
+ break;
+ }
+ } else {
+ if (iter->async_tx.phys == current_desc) {
+ current_cleaned = 0;
+ break;
+ }
+ }
+ }
+
+ if ((busy == 0) && !list_empty(&mv_chan->chain)) {
+ if (current_cleaned) {
+ /*
+ * current descriptor cleaned and removed, run
+ * from list head
+ */
+ iter = list_entry(mv_chan->chain.next,
+ struct mv_xor_desc_slot,
+ node);
+ mv_chan_start_new_chain(mv_chan, iter);
+ } else {
+ if (!list_is_last(&iter->node, &mv_chan->chain)) {
+ /*
+ * descriptors are still waiting after
+ * current, trigger them
+ */
+ iter = list_entry(iter->node.next,
+ struct mv_xor_desc_slot,
+ node);
+ mv_chan_start_new_chain(mv_chan, iter);
+ } else {
+ /*
+ * some descriptors are still waiting
+ * to be cleaned
+ */
+ tasklet_schedule(&mv_chan->irq_tasklet);
+ }
+ }
+ }
+
+ if (cookie > 0)
+ mv_chan->dmachan.completed_cookie = cookie;
+}
+
+static void mv_xor_tasklet(struct tasklet_struct *t)
+{
+ struct mv_xor_chan *chan = from_tasklet(chan, t, irq_tasklet);
+
+ spin_lock(&chan->lock);
+ mv_chan_slot_cleanup(chan);
+ spin_unlock(&chan->lock);
+}
+
+static struct mv_xor_desc_slot *
+mv_chan_alloc_slot(struct mv_xor_chan *mv_chan)
+{
+ struct mv_xor_desc_slot *iter;
+
+ spin_lock_bh(&mv_chan->lock);
+
+ if (!list_empty(&mv_chan->free_slots)) {
+ iter = list_first_entry(&mv_chan->free_slots,
+ struct mv_xor_desc_slot,
+ node);
+
+ list_move_tail(&iter->node, &mv_chan->allocated_slots);
+
+ spin_unlock_bh(&mv_chan->lock);
+
+ /* pre-ack descriptor */
+ async_tx_ack(&iter->async_tx);
+ iter->async_tx.cookie = -EBUSY;
+
+ return iter;
+
+ }
+
+ spin_unlock_bh(&mv_chan->lock);
+
+ /* try to free some slots if the allocation fails */
+ tasklet_schedule(&mv_chan->irq_tasklet);
+
+ return NULL;
+}
+
+/************************ DMA engine API functions ****************************/
+static dma_cookie_t
+mv_xor_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct mv_xor_desc_slot *sw_desc = to_mv_xor_slot(tx);
+ struct mv_xor_chan *mv_chan = to_mv_xor_chan(tx->chan);
+ struct mv_xor_desc_slot *old_chain_tail;
+ dma_cookie_t cookie;
+ int new_hw_chain = 1;
+
+ dev_dbg(mv_chan_to_devp(mv_chan),
+ "%s sw_desc %p: async_tx %p\n",
+ __func__, sw_desc, &sw_desc->async_tx);
+
+ spin_lock_bh(&mv_chan->lock);
+ cookie = dma_cookie_assign(tx);
+
+ if (list_empty(&mv_chan->chain))
+ list_move_tail(&sw_desc->node, &mv_chan->chain);
+ else {
+ new_hw_chain = 0;
+
+ old_chain_tail = list_entry(mv_chan->chain.prev,
+ struct mv_xor_desc_slot,
+ node);
+ list_move_tail(&sw_desc->node, &mv_chan->chain);
+
+ dev_dbg(mv_chan_to_devp(mv_chan), "Append to last desc %pa\n",
+ &old_chain_tail->async_tx.phys);
+
+ /* fix up the hardware chain */
+ mv_desc_set_next_desc(old_chain_tail, sw_desc->async_tx.phys);
+
+ /* if the channel is not busy */
+ if (!mv_chan_is_busy(mv_chan)) {
+ u32 current_desc = mv_chan_get_current_desc(mv_chan);
+ /*
+ * and the curren desc is the end of the chain before
+ * the append, then we need to start the channel
+ */
+ if (current_desc == old_chain_tail->async_tx.phys)
+ new_hw_chain = 1;
+ }
+ }
+
+ if (new_hw_chain)
+ mv_chan_start_new_chain(mv_chan, sw_desc);
+
+ spin_unlock_bh(&mv_chan->lock);
+
+ return cookie;
+}
+
+/* returns the number of allocated descriptors */
+static int mv_xor_alloc_chan_resources(struct dma_chan *chan)
+{
+ void *virt_desc;
+ dma_addr_t dma_desc;
+ int idx;
+ struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
+ struct mv_xor_desc_slot *slot = NULL;
+ int num_descs_in_pool = MV_XOR_POOL_SIZE/MV_XOR_SLOT_SIZE;
+
+ /* Allocate descriptor slots */
+ idx = mv_chan->slots_allocated;
+ while (idx < num_descs_in_pool) {
+ slot = kzalloc(sizeof(*slot), GFP_KERNEL);
+ if (!slot) {
+ dev_info(mv_chan_to_devp(mv_chan),
+ "channel only initialized %d descriptor slots",
+ idx);
+ break;
+ }
+ virt_desc = mv_chan->dma_desc_pool_virt;
+ slot->hw_desc = virt_desc + idx * MV_XOR_SLOT_SIZE;
+
+ dma_async_tx_descriptor_init(&slot->async_tx, chan);
+ slot->async_tx.tx_submit = mv_xor_tx_submit;
+ INIT_LIST_HEAD(&slot->node);
+ INIT_LIST_HEAD(&slot->sg_tx_list);
+ dma_desc = mv_chan->dma_desc_pool;
+ slot->async_tx.phys = dma_desc + idx * MV_XOR_SLOT_SIZE;
+ slot->idx = idx++;
+
+ spin_lock_bh(&mv_chan->lock);
+ mv_chan->slots_allocated = idx;
+ list_add_tail(&slot->node, &mv_chan->free_slots);
+ spin_unlock_bh(&mv_chan->lock);
+ }
+
+ dev_dbg(mv_chan_to_devp(mv_chan),
+ "allocated %d descriptor slots\n",
+ mv_chan->slots_allocated);
+
+ return mv_chan->slots_allocated ? : -ENOMEM;
+}
+
+/*
+ * Check if source or destination is an PCIe/IO address (non-SDRAM) and add
+ * a new MBus window if necessary. Use a cache for these check so that
+ * the MMIO mapped registers don't have to be accessed for this check
+ * to speed up this process.
+ */
+static int mv_xor_add_io_win(struct mv_xor_chan *mv_chan, u32 addr)
+{
+ struct mv_xor_device *xordev = mv_chan->xordev;
+ void __iomem *base = mv_chan->mmr_high_base;
+ u32 win_enable;
+ u32 size;
+ u8 target, attr;
+ int ret;
+ int i;
+
+ /* Nothing needs to get done for the Armada 3700 */
+ if (xordev->xor_type == XOR_ARMADA_37XX)
+ return 0;
+
+ /*
+ * Loop over the cached windows to check, if the requested area
+ * is already mapped. If this the case, nothing needs to be done
+ * and we can return.
+ */
+ for (i = 0; i < WINDOW_COUNT; i++) {
+ if (addr >= xordev->win_start[i] &&
+ addr <= xordev->win_end[i]) {
+ /* Window is already mapped */
+ return 0;
+ }
+ }
+
+ /*
+ * The window is not mapped, so we need to create the new mapping
+ */
+
+ /* If no IO window is found that addr has to be located in SDRAM */
+ ret = mvebu_mbus_get_io_win_info(addr, &size, &target, &attr);
+ if (ret < 0)
+ return 0;
+
+ /*
+ * Mask the base addr 'addr' according to 'size' read back from the
+ * MBus window. Otherwise we might end up with an address located
+ * somewhere in the middle of this area here.
+ */
+ size -= 1;
+ addr &= ~size;
+
+ /*
+ * Reading one of both enabled register is enough, as they are always
+ * programmed to the identical values
+ */
+ win_enable = readl(base + WINDOW_BAR_ENABLE(0));
+
+ /* Set 'i' to the first free window to write the new values to */
+ i = ffs(~win_enable) - 1;
+ if (i >= WINDOW_COUNT)
+ return -ENOMEM;
+
+ writel((addr & 0xffff0000) | (attr << 8) | target,
+ base + WINDOW_BASE(i));
+ writel(size & 0xffff0000, base + WINDOW_SIZE(i));
+
+ /* Fill the caching variables for later use */
+ xordev->win_start[i] = addr;
+ xordev->win_end[i] = addr + size;
+
+ win_enable |= (1 << i);
+ win_enable |= 3 << (16 + (2 * i));
+ writel(win_enable, base + WINDOW_BAR_ENABLE(0));
+ writel(win_enable, base + WINDOW_BAR_ENABLE(1));
+
+ return 0;
+}
+
+static struct dma_async_tx_descriptor *
+mv_xor_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
+ unsigned int src_cnt, size_t len, unsigned long flags)
+{
+ struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
+ struct mv_xor_desc_slot *sw_desc;
+ int ret;
+
+ if (unlikely(len < MV_XOR_MIN_BYTE_COUNT))
+ return NULL;
+
+ BUG_ON(len > MV_XOR_MAX_BYTE_COUNT);
+
+ dev_dbg(mv_chan_to_devp(mv_chan),
+ "%s src_cnt: %d len: %zu dest %pad flags: %ld\n",
+ __func__, src_cnt, len, &dest, flags);
+
+ /* Check if a new window needs to get added for 'dest' */
+ ret = mv_xor_add_io_win(mv_chan, dest);
+ if (ret)
+ return NULL;
+
+ sw_desc = mv_chan_alloc_slot(mv_chan);
+ if (sw_desc) {
+ sw_desc->type = DMA_XOR;
+ sw_desc->async_tx.flags = flags;
+ mv_desc_init(sw_desc, dest, len, flags);
+ if (mv_chan->op_in_desc == XOR_MODE_IN_DESC)
+ mv_desc_set_mode(sw_desc);
+ while (src_cnt--) {
+ /* Check if a new window needs to get added for 'src' */
+ ret = mv_xor_add_io_win(mv_chan, src[src_cnt]);
+ if (ret)
+ return NULL;
+ mv_desc_set_src_addr(sw_desc, src_cnt, src[src_cnt]);
+ }
+ }
+
+ dev_dbg(mv_chan_to_devp(mv_chan),
+ "%s sw_desc %p async_tx %p \n",
+ __func__, sw_desc, &sw_desc->async_tx);
+ return sw_desc ? &sw_desc->async_tx : NULL;
+}
+
+static struct dma_async_tx_descriptor *
+mv_xor_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
+ size_t len, unsigned long flags)
+{
+ /*
+ * A MEMCPY operation is identical to an XOR operation with only
+ * a single source address.
+ */
+ return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags);
+}
+
+static struct dma_async_tx_descriptor *
+mv_xor_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
+{
+ struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
+ dma_addr_t src, dest;
+ size_t len;
+
+ src = mv_chan->dummy_src_addr;
+ dest = mv_chan->dummy_dst_addr;
+ len = MV_XOR_MIN_BYTE_COUNT;
+
+ /*
+ * We implement the DMA_INTERRUPT operation as a minimum sized
+ * XOR operation with a single dummy source address.
+ */
+ return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags);
+}
+
+static void mv_xor_free_chan_resources(struct dma_chan *chan)
+{
+ struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
+ struct mv_xor_desc_slot *iter, *_iter;
+ int in_use_descs = 0;
+
+ spin_lock_bh(&mv_chan->lock);
+
+ mv_chan_slot_cleanup(mv_chan);
+
+ list_for_each_entry_safe(iter, _iter, &mv_chan->chain,
+ node) {
+ in_use_descs++;
+ list_move_tail(&iter->node, &mv_chan->free_slots);
+ }
+ list_for_each_entry_safe(iter, _iter, &mv_chan->completed_slots,
+ node) {
+ in_use_descs++;
+ list_move_tail(&iter->node, &mv_chan->free_slots);
+ }
+ list_for_each_entry_safe(iter, _iter, &mv_chan->allocated_slots,
+ node) {
+ in_use_descs++;
+ list_move_tail(&iter->node, &mv_chan->free_slots);
+ }
+ list_for_each_entry_safe_reverse(
+ iter, _iter, &mv_chan->free_slots, node) {
+ list_del(&iter->node);
+ kfree(iter);
+ mv_chan->slots_allocated--;
+ }
+
+ dev_dbg(mv_chan_to_devp(mv_chan), "%s slots_allocated %d\n",
+ __func__, mv_chan->slots_allocated);
+ spin_unlock_bh(&mv_chan->lock);
+
+ if (in_use_descs)
+ dev_err(mv_chan_to_devp(mv_chan),
+ "freeing %d in use descriptors!\n", in_use_descs);
+}
+
+/**
+ * mv_xor_status - poll the status of an XOR transaction
+ * @chan: XOR channel handle
+ * @cookie: XOR transaction identifier
+ * @txstate: XOR transactions state holder (or NULL)
+ */
+static enum dma_status mv_xor_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
+ enum dma_status ret;
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ if (ret == DMA_COMPLETE)
+ return ret;
+
+ spin_lock_bh(&mv_chan->lock);
+ mv_chan_slot_cleanup(mv_chan);
+ spin_unlock_bh(&mv_chan->lock);
+
+ return dma_cookie_status(chan, cookie, txstate);
+}
+
+static void mv_chan_dump_regs(struct mv_xor_chan *chan)
+{
+ u32 val;
+
+ val = readl_relaxed(XOR_CONFIG(chan));
+ dev_err(mv_chan_to_devp(chan), "config 0x%08x\n", val);
+
+ val = readl_relaxed(XOR_ACTIVATION(chan));
+ dev_err(mv_chan_to_devp(chan), "activation 0x%08x\n", val);
+
+ val = readl_relaxed(XOR_INTR_CAUSE(chan));
+ dev_err(mv_chan_to_devp(chan), "intr cause 0x%08x\n", val);
+
+ val = readl_relaxed(XOR_INTR_MASK(chan));
+ dev_err(mv_chan_to_devp(chan), "intr mask 0x%08x\n", val);
+
+ val = readl_relaxed(XOR_ERROR_CAUSE(chan));
+ dev_err(mv_chan_to_devp(chan), "error cause 0x%08x\n", val);
+
+ val = readl_relaxed(XOR_ERROR_ADDR(chan));
+ dev_err(mv_chan_to_devp(chan), "error addr 0x%08x\n", val);
+}
+
+static void mv_chan_err_interrupt_handler(struct mv_xor_chan *chan,
+ u32 intr_cause)
+{
+ if (intr_cause & XOR_INT_ERR_DECODE) {
+ dev_dbg(mv_chan_to_devp(chan), "ignoring address decode error\n");
+ return;
+ }
+
+ dev_err(mv_chan_to_devp(chan), "error on chan %d. intr cause 0x%08x\n",
+ chan->idx, intr_cause);
+
+ mv_chan_dump_regs(chan);
+ WARN_ON(1);
+}
+
+static irqreturn_t mv_xor_interrupt_handler(int irq, void *data)
+{
+ struct mv_xor_chan *chan = data;
+ u32 intr_cause = mv_chan_get_intr_cause(chan);
+
+ dev_dbg(mv_chan_to_devp(chan), "intr cause %x\n", intr_cause);
+
+ if (intr_cause & XOR_INTR_ERRORS)
+ mv_chan_err_interrupt_handler(chan, intr_cause);
+
+ tasklet_schedule(&chan->irq_tasklet);
+
+ mv_chan_clear_eoc_cause(chan);
+
+ return IRQ_HANDLED;
+}
+
+static void mv_xor_issue_pending(struct dma_chan *chan)
+{
+ struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
+
+ if (mv_chan->pending >= MV_XOR_THRESHOLD) {
+ mv_chan->pending = 0;
+ mv_chan_activate(mv_chan);
+ }
+}
+
+/*
+ * Perform a transaction to verify the HW works.
+ */
+
+static int mv_chan_memcpy_self_test(struct mv_xor_chan *mv_chan)
+{
+ int i, ret;
+ void *src, *dest;
+ dma_addr_t src_dma, dest_dma;
+ struct dma_chan *dma_chan;
+ dma_cookie_t cookie;
+ struct dma_async_tx_descriptor *tx;
+ struct dmaengine_unmap_data *unmap;
+ int err = 0;
+
+ src = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!src)
+ return -ENOMEM;
+
+ dest = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!dest) {
+ kfree(src);
+ return -ENOMEM;
+ }
+
+ /* Fill in src buffer */
+ for (i = 0; i < PAGE_SIZE; i++)
+ ((u8 *) src)[i] = (u8)i;
+
+ dma_chan = &mv_chan->dmachan;
+ if (mv_xor_alloc_chan_resources(dma_chan) < 1) {
+ err = -ENODEV;
+ goto out;
+ }
+
+ unmap = dmaengine_get_unmap_data(dma_chan->device->dev, 2, GFP_KERNEL);
+ if (!unmap) {
+ err = -ENOMEM;
+ goto free_resources;
+ }
+
+ src_dma = dma_map_page(dma_chan->device->dev, virt_to_page(src),
+ offset_in_page(src), PAGE_SIZE,
+ DMA_TO_DEVICE);
+ unmap->addr[0] = src_dma;
+
+ ret = dma_mapping_error(dma_chan->device->dev, src_dma);
+ if (ret) {
+ err = -ENOMEM;
+ goto free_resources;
+ }
+ unmap->to_cnt = 1;
+
+ dest_dma = dma_map_page(dma_chan->device->dev, virt_to_page(dest),
+ offset_in_page(dest), PAGE_SIZE,
+ DMA_FROM_DEVICE);
+ unmap->addr[1] = dest_dma;
+
+ ret = dma_mapping_error(dma_chan->device->dev, dest_dma);
+ if (ret) {
+ err = -ENOMEM;
+ goto free_resources;
+ }
+ unmap->from_cnt = 1;
+ unmap->len = PAGE_SIZE;
+
+ tx = mv_xor_prep_dma_memcpy(dma_chan, dest_dma, src_dma,
+ PAGE_SIZE, 0);
+ if (!tx) {
+ dev_err(dma_chan->device->dev,
+ "Self-test cannot prepare operation, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+ cookie = mv_xor_tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ dev_err(dma_chan->device->dev,
+ "Self-test submit error, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+ mv_xor_issue_pending(dma_chan);
+ async_tx_ack(tx);
+ msleep(1);
+
+ if (mv_xor_status(dma_chan, cookie, NULL) !=
+ DMA_COMPLETE) {
+ dev_err(dma_chan->device->dev,
+ "Self-test copy timed out, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+ dma_sync_single_for_cpu(dma_chan->device->dev, dest_dma,
+ PAGE_SIZE, DMA_FROM_DEVICE);
+ if (memcmp(src, dest, PAGE_SIZE)) {
+ dev_err(dma_chan->device->dev,
+ "Self-test copy failed compare, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+free_resources:
+ dmaengine_unmap_put(unmap);
+ mv_xor_free_chan_resources(dma_chan);
+out:
+ kfree(src);
+ kfree(dest);
+ return err;
+}
+
+#define MV_XOR_NUM_SRC_TEST 4 /* must be <= 15 */
+static int
+mv_chan_xor_self_test(struct mv_xor_chan *mv_chan)
+{
+ int i, src_idx, ret;
+ struct page *dest;
+ struct page *xor_srcs[MV_XOR_NUM_SRC_TEST];
+ dma_addr_t dma_srcs[MV_XOR_NUM_SRC_TEST];
+ dma_addr_t dest_dma;
+ struct dma_async_tx_descriptor *tx;
+ struct dmaengine_unmap_data *unmap;
+ struct dma_chan *dma_chan;
+ dma_cookie_t cookie;
+ u8 cmp_byte = 0;
+ u32 cmp_word;
+ int err = 0;
+ int src_count = MV_XOR_NUM_SRC_TEST;
+
+ for (src_idx = 0; src_idx < src_count; src_idx++) {
+ xor_srcs[src_idx] = alloc_page(GFP_KERNEL);
+ if (!xor_srcs[src_idx]) {
+ while (src_idx--)
+ __free_page(xor_srcs[src_idx]);
+ return -ENOMEM;
+ }
+ }
+
+ dest = alloc_page(GFP_KERNEL);
+ if (!dest) {
+ while (src_idx--)
+ __free_page(xor_srcs[src_idx]);
+ return -ENOMEM;
+ }
+
+ /* Fill in src buffers */
+ for (src_idx = 0; src_idx < src_count; src_idx++) {
+ u8 *ptr = page_address(xor_srcs[src_idx]);
+ for (i = 0; i < PAGE_SIZE; i++)
+ ptr[i] = (1 << src_idx);
+ }
+
+ for (src_idx = 0; src_idx < src_count; src_idx++)
+ cmp_byte ^= (u8) (1 << src_idx);
+
+ cmp_word = (cmp_byte << 24) | (cmp_byte << 16) |
+ (cmp_byte << 8) | cmp_byte;
+
+ memset(page_address(dest), 0, PAGE_SIZE);
+
+ dma_chan = &mv_chan->dmachan;
+ if (mv_xor_alloc_chan_resources(dma_chan) < 1) {
+ err = -ENODEV;
+ goto out;
+ }
+
+ unmap = dmaengine_get_unmap_data(dma_chan->device->dev, src_count + 1,
+ GFP_KERNEL);
+ if (!unmap) {
+ err = -ENOMEM;
+ goto free_resources;
+ }
+
+ /* test xor */
+ for (i = 0; i < src_count; i++) {
+ unmap->addr[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i],
+ 0, PAGE_SIZE, DMA_TO_DEVICE);
+ dma_srcs[i] = unmap->addr[i];
+ ret = dma_mapping_error(dma_chan->device->dev, unmap->addr[i]);
+ if (ret) {
+ err = -ENOMEM;
+ goto free_resources;
+ }
+ unmap->to_cnt++;
+ }
+
+ unmap->addr[src_count] = dma_map_page(dma_chan->device->dev, dest, 0, PAGE_SIZE,
+ DMA_FROM_DEVICE);
+ dest_dma = unmap->addr[src_count];
+ ret = dma_mapping_error(dma_chan->device->dev, unmap->addr[src_count]);
+ if (ret) {
+ err = -ENOMEM;
+ goto free_resources;
+ }
+ unmap->from_cnt = 1;
+ unmap->len = PAGE_SIZE;
+
+ tx = mv_xor_prep_dma_xor(dma_chan, dest_dma, dma_srcs,
+ src_count, PAGE_SIZE, 0);
+ if (!tx) {
+ dev_err(dma_chan->device->dev,
+ "Self-test cannot prepare operation, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+ cookie = mv_xor_tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ dev_err(dma_chan->device->dev,
+ "Self-test submit error, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+ mv_xor_issue_pending(dma_chan);
+ async_tx_ack(tx);
+ msleep(8);
+
+ if (mv_xor_status(dma_chan, cookie, NULL) !=
+ DMA_COMPLETE) {
+ dev_err(dma_chan->device->dev,
+ "Self-test xor timed out, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+ dma_sync_single_for_cpu(dma_chan->device->dev, dest_dma,
+ PAGE_SIZE, DMA_FROM_DEVICE);
+ for (i = 0; i < (PAGE_SIZE / sizeof(u32)); i++) {
+ u32 *ptr = page_address(dest);
+ if (ptr[i] != cmp_word) {
+ dev_err(dma_chan->device->dev,
+ "Self-test xor failed compare, disabling. index %d, data %x, expected %x\n",
+ i, ptr[i], cmp_word);
+ err = -ENODEV;
+ goto free_resources;
+ }
+ }
+
+free_resources:
+ dmaengine_unmap_put(unmap);
+ mv_xor_free_chan_resources(dma_chan);
+out:
+ src_idx = src_count;
+ while (src_idx--)
+ __free_page(xor_srcs[src_idx]);
+ __free_page(dest);
+ return err;
+}
+
+static int mv_xor_channel_remove(struct mv_xor_chan *mv_chan)
+{
+ struct dma_chan *chan, *_chan;
+ struct device *dev = mv_chan->dmadev.dev;
+
+ dma_async_device_unregister(&mv_chan->dmadev);
+
+ dma_free_coherent(dev, MV_XOR_POOL_SIZE,
+ mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool);
+ dma_unmap_single(dev, mv_chan->dummy_src_addr,
+ MV_XOR_MIN_BYTE_COUNT, DMA_FROM_DEVICE);
+ dma_unmap_single(dev, mv_chan->dummy_dst_addr,
+ MV_XOR_MIN_BYTE_COUNT, DMA_TO_DEVICE);
+
+ list_for_each_entry_safe(chan, _chan, &mv_chan->dmadev.channels,
+ device_node) {
+ list_del(&chan->device_node);
+ }
+
+ free_irq(mv_chan->irq, mv_chan);
+
+ return 0;
+}
+
+static struct mv_xor_chan *
+mv_xor_channel_add(struct mv_xor_device *xordev,
+ struct platform_device *pdev,
+ int idx, dma_cap_mask_t cap_mask, int irq)
+{
+ int ret = 0;
+ struct mv_xor_chan *mv_chan;
+ struct dma_device *dma_dev;
+
+ mv_chan = devm_kzalloc(&pdev->dev, sizeof(*mv_chan), GFP_KERNEL);
+ if (!mv_chan)
+ return ERR_PTR(-ENOMEM);
+
+ mv_chan->idx = idx;
+ mv_chan->irq = irq;
+ if (xordev->xor_type == XOR_ORION)
+ mv_chan->op_in_desc = XOR_MODE_IN_REG;
+ else
+ mv_chan->op_in_desc = XOR_MODE_IN_DESC;
+
+ dma_dev = &mv_chan->dmadev;
+ dma_dev->dev = &pdev->dev;
+ mv_chan->xordev = xordev;
+
+ /*
+ * These source and destination dummy buffers are used to implement
+ * a DMA_INTERRUPT operation as a minimum-sized XOR operation.
+ * Hence, we only need to map the buffers at initialization-time.
+ */
+ mv_chan->dummy_src_addr = dma_map_single(dma_dev->dev,
+ mv_chan->dummy_src, MV_XOR_MIN_BYTE_COUNT, DMA_FROM_DEVICE);
+ mv_chan->dummy_dst_addr = dma_map_single(dma_dev->dev,
+ mv_chan->dummy_dst, MV_XOR_MIN_BYTE_COUNT, DMA_TO_DEVICE);
+
+ /* allocate coherent memory for hardware descriptors
+ * note: writecombine gives slightly better performance, but
+ * requires that we explicitly flush the writes
+ */
+ mv_chan->dma_desc_pool_virt =
+ dma_alloc_wc(&pdev->dev, MV_XOR_POOL_SIZE, &mv_chan->dma_desc_pool,
+ GFP_KERNEL);
+ if (!mv_chan->dma_desc_pool_virt)
+ return ERR_PTR(-ENOMEM);
+
+ /* discover transaction capabilites from the platform data */
+ dma_dev->cap_mask = cap_mask;
+
+ INIT_LIST_HEAD(&dma_dev->channels);
+
+ /* set base routines */
+ dma_dev->device_alloc_chan_resources = mv_xor_alloc_chan_resources;
+ dma_dev->device_free_chan_resources = mv_xor_free_chan_resources;
+ dma_dev->device_tx_status = mv_xor_status;
+ dma_dev->device_issue_pending = mv_xor_issue_pending;
+
+ /* set prep routines based on capability */
+ if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask))
+ dma_dev->device_prep_dma_interrupt = mv_xor_prep_dma_interrupt;
+ if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask))
+ dma_dev->device_prep_dma_memcpy = mv_xor_prep_dma_memcpy;
+ if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
+ dma_dev->max_xor = 8;
+ dma_dev->device_prep_dma_xor = mv_xor_prep_dma_xor;
+ }
+
+ mv_chan->mmr_base = xordev->xor_base;
+ mv_chan->mmr_high_base = xordev->xor_high_base;
+ tasklet_setup(&mv_chan->irq_tasklet, mv_xor_tasklet);
+
+ /* clear errors before enabling interrupts */
+ mv_chan_clear_err_status(mv_chan);
+
+ ret = request_irq(mv_chan->irq, mv_xor_interrupt_handler,
+ 0, dev_name(&pdev->dev), mv_chan);
+ if (ret)
+ goto err_free_dma;
+
+ mv_chan_unmask_interrupts(mv_chan);
+
+ if (mv_chan->op_in_desc == XOR_MODE_IN_DESC)
+ mv_chan_set_mode(mv_chan, XOR_OPERATION_MODE_IN_DESC);
+ else
+ mv_chan_set_mode(mv_chan, XOR_OPERATION_MODE_XOR);
+
+ spin_lock_init(&mv_chan->lock);
+ INIT_LIST_HEAD(&mv_chan->chain);
+ INIT_LIST_HEAD(&mv_chan->completed_slots);
+ INIT_LIST_HEAD(&mv_chan->free_slots);
+ INIT_LIST_HEAD(&mv_chan->allocated_slots);
+ mv_chan->dmachan.device = dma_dev;
+ dma_cookie_init(&mv_chan->dmachan);
+
+ list_add_tail(&mv_chan->dmachan.device_node, &dma_dev->channels);
+
+ if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
+ ret = mv_chan_memcpy_self_test(mv_chan);
+ dev_dbg(&pdev->dev, "memcpy self test returned %d\n", ret);
+ if (ret)
+ goto err_free_irq;
+ }
+
+ if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
+ ret = mv_chan_xor_self_test(mv_chan);
+ dev_dbg(&pdev->dev, "xor self test returned %d\n", ret);
+ if (ret)
+ goto err_free_irq;
+ }
+
+ dev_info(&pdev->dev, "Marvell XOR (%s): ( %s%s%s)\n",
+ mv_chan->op_in_desc ? "Descriptor Mode" : "Registers Mode",
+ dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "",
+ dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "",
+ dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "intr " : "");
+
+ ret = dma_async_device_register(dma_dev);
+ if (ret)
+ goto err_free_irq;
+
+ return mv_chan;
+
+err_free_irq:
+ free_irq(mv_chan->irq, mv_chan);
+err_free_dma:
+ dma_free_coherent(&pdev->dev, MV_XOR_POOL_SIZE,
+ mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool);
+ return ERR_PTR(ret);
+}
+
+static void
+mv_xor_conf_mbus_windows(struct mv_xor_device *xordev,
+ const struct mbus_dram_target_info *dram)
+{
+ void __iomem *base = xordev->xor_high_base;
+ u32 win_enable = 0;
+ int i;
+
+ for (i = 0; i < 8; i++) {
+ writel(0, base + WINDOW_BASE(i));
+ writel(0, base + WINDOW_SIZE(i));
+ if (i < 4)
+ writel(0, base + WINDOW_REMAP_HIGH(i));
+ }
+
+ for (i = 0; i < dram->num_cs; i++) {
+ const struct mbus_dram_window *cs = dram->cs + i;
+
+ writel((cs->base & 0xffff0000) |
+ (cs->mbus_attr << 8) |
+ dram->mbus_dram_target_id, base + WINDOW_BASE(i));
+ writel((cs->size - 1) & 0xffff0000, base + WINDOW_SIZE(i));
+
+ /* Fill the caching variables for later use */
+ xordev->win_start[i] = cs->base;
+ xordev->win_end[i] = cs->base + cs->size - 1;
+
+ win_enable |= (1 << i);
+ win_enable |= 3 << (16 + (2 * i));
+ }
+
+ writel(win_enable, base + WINDOW_BAR_ENABLE(0));
+ writel(win_enable, base + WINDOW_BAR_ENABLE(1));
+ writel(0, base + WINDOW_OVERRIDE_CTRL(0));
+ writel(0, base + WINDOW_OVERRIDE_CTRL(1));
+}
+
+static void
+mv_xor_conf_mbus_windows_a3700(struct mv_xor_device *xordev)
+{
+ void __iomem *base = xordev->xor_high_base;
+ u32 win_enable = 0;
+ int i;
+
+ for (i = 0; i < 8; i++) {
+ writel(0, base + WINDOW_BASE(i));
+ writel(0, base + WINDOW_SIZE(i));
+ if (i < 4)
+ writel(0, base + WINDOW_REMAP_HIGH(i));
+ }
+ /*
+ * For Armada3700 open default 4GB Mbus window. The dram
+ * related configuration are done at AXIS level.
+ */
+ writel(0xffff0000, base + WINDOW_SIZE(0));
+ win_enable |= 1;
+ win_enable |= 3 << 16;
+
+ writel(win_enable, base + WINDOW_BAR_ENABLE(0));
+ writel(win_enable, base + WINDOW_BAR_ENABLE(1));
+ writel(0, base + WINDOW_OVERRIDE_CTRL(0));
+ writel(0, base + WINDOW_OVERRIDE_CTRL(1));
+}
+
+/*
+ * Since this XOR driver is basically used only for RAID5, we don't
+ * need to care about synchronizing ->suspend with DMA activity,
+ * because the DMA engine will naturally be quiet due to the block
+ * devices being suspended.
+ */
+static int mv_xor_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct mv_xor_device *xordev = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) {
+ struct mv_xor_chan *mv_chan = xordev->channels[i];
+
+ if (!mv_chan)
+ continue;
+
+ mv_chan->saved_config_reg =
+ readl_relaxed(XOR_CONFIG(mv_chan));
+ mv_chan->saved_int_mask_reg =
+ readl_relaxed(XOR_INTR_MASK(mv_chan));
+ }
+
+ return 0;
+}
+
+static int mv_xor_resume(struct platform_device *dev)
+{
+ struct mv_xor_device *xordev = platform_get_drvdata(dev);
+ const struct mbus_dram_target_info *dram;
+ int i;
+
+ for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) {
+ struct mv_xor_chan *mv_chan = xordev->channels[i];
+
+ if (!mv_chan)
+ continue;
+
+ writel_relaxed(mv_chan->saved_config_reg,
+ XOR_CONFIG(mv_chan));
+ writel_relaxed(mv_chan->saved_int_mask_reg,
+ XOR_INTR_MASK(mv_chan));
+ }
+
+ if (xordev->xor_type == XOR_ARMADA_37XX) {
+ mv_xor_conf_mbus_windows_a3700(xordev);
+ return 0;
+ }
+
+ dram = mv_mbus_dram_info();
+ if (dram)
+ mv_xor_conf_mbus_windows(xordev, dram);
+
+ return 0;
+}
+
+static const struct of_device_id mv_xor_dt_ids[] = {
+ { .compatible = "marvell,orion-xor", .data = (void *)XOR_ORION },
+ { .compatible = "marvell,armada-380-xor", .data = (void *)XOR_ARMADA_38X },
+ { .compatible = "marvell,armada-3700-xor", .data = (void *)XOR_ARMADA_37XX },
+ {},
+};
+
+static unsigned int mv_xor_engine_count;
+
+static int mv_xor_probe(struct platform_device *pdev)
+{
+ const struct mbus_dram_target_info *dram;
+ struct mv_xor_device *xordev;
+ struct mv_xor_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ struct resource *res;
+ unsigned int max_engines, max_channels;
+ int i, ret;
+
+ dev_notice(&pdev->dev, "Marvell shared XOR driver\n");
+
+ xordev = devm_kzalloc(&pdev->dev, sizeof(*xordev), GFP_KERNEL);
+ if (!xordev)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ xordev->xor_base = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (!xordev->xor_base)
+ return -EBUSY;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res)
+ return -ENODEV;
+
+ xordev->xor_high_base = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (!xordev->xor_high_base)
+ return -EBUSY;
+
+ platform_set_drvdata(pdev, xordev);
+
+
+ /*
+ * We need to know which type of XOR device we use before
+ * setting up. In non-dt case it can only be the legacy one.
+ */
+ xordev->xor_type = XOR_ORION;
+ if (pdev->dev.of_node) {
+ const struct of_device_id *of_id =
+ of_match_device(mv_xor_dt_ids,
+ &pdev->dev);
+
+ xordev->xor_type = (uintptr_t)of_id->data;
+ }
+
+ /*
+ * (Re-)program MBUS remapping windows if we are asked to.
+ */
+ if (xordev->xor_type == XOR_ARMADA_37XX) {
+ mv_xor_conf_mbus_windows_a3700(xordev);
+ } else {
+ dram = mv_mbus_dram_info();
+ if (dram)
+ mv_xor_conf_mbus_windows(xordev, dram);
+ }
+
+ /* Not all platforms can gate the clock, so it is not
+ * an error if the clock does not exists.
+ */
+ xordev->clk = clk_get(&pdev->dev, NULL);
+ if (!IS_ERR(xordev->clk))
+ clk_prepare_enable(xordev->clk);
+
+ /*
+ * We don't want to have more than one channel per CPU in
+ * order for async_tx to perform well. So we limit the number
+ * of engines and channels so that we take into account this
+ * constraint. Note that we also want to use channels from
+ * separate engines when possible. For dual-CPU Armada 3700
+ * SoC with single XOR engine allow using its both channels.
+ */
+ max_engines = num_present_cpus();
+ if (xordev->xor_type == XOR_ARMADA_37XX)
+ max_channels = num_present_cpus();
+ else
+ max_channels = min_t(unsigned int,
+ MV_XOR_MAX_CHANNELS,
+ DIV_ROUND_UP(num_present_cpus(), 2));
+
+ if (mv_xor_engine_count >= max_engines)
+ return 0;
+
+ if (pdev->dev.of_node) {
+ struct device_node *np;
+ int i = 0;
+
+ for_each_child_of_node(pdev->dev.of_node, np) {
+ struct mv_xor_chan *chan;
+ dma_cap_mask_t cap_mask;
+ int irq;
+
+ if (i >= max_channels)
+ continue;
+
+ dma_cap_zero(cap_mask);
+ dma_cap_set(DMA_MEMCPY, cap_mask);
+ dma_cap_set(DMA_XOR, cap_mask);
+ dma_cap_set(DMA_INTERRUPT, cap_mask);
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (!irq) {
+ ret = -ENODEV;
+ goto err_channel_add;
+ }
+
+ chan = mv_xor_channel_add(xordev, pdev, i,
+ cap_mask, irq);
+ if (IS_ERR(chan)) {
+ ret = PTR_ERR(chan);
+ irq_dispose_mapping(irq);
+ goto err_channel_add;
+ }
+
+ xordev->channels[i] = chan;
+ i++;
+ }
+ } else if (pdata && pdata->channels) {
+ for (i = 0; i < max_channels; i++) {
+ struct mv_xor_channel_data *cd;
+ struct mv_xor_chan *chan;
+ int irq;
+
+ cd = &pdata->channels[i];
+ irq = platform_get_irq(pdev, i);
+ if (irq < 0) {
+ ret = irq;
+ goto err_channel_add;
+ }
+
+ chan = mv_xor_channel_add(xordev, pdev, i,
+ cd->cap_mask, irq);
+ if (IS_ERR(chan)) {
+ ret = PTR_ERR(chan);
+ goto err_channel_add;
+ }
+
+ xordev->channels[i] = chan;
+ }
+ }
+
+ return 0;
+
+err_channel_add:
+ for (i = 0; i < MV_XOR_MAX_CHANNELS; i++)
+ if (xordev->channels[i]) {
+ mv_xor_channel_remove(xordev->channels[i]);
+ if (pdev->dev.of_node)
+ irq_dispose_mapping(xordev->channels[i]->irq);
+ }
+
+ if (!IS_ERR(xordev->clk)) {
+ clk_disable_unprepare(xordev->clk);
+ clk_put(xordev->clk);
+ }
+
+ return ret;
+}
+
+static struct platform_driver mv_xor_driver = {
+ .probe = mv_xor_probe,
+ .suspend = mv_xor_suspend,
+ .resume = mv_xor_resume,
+ .driver = {
+ .name = MV_XOR_NAME,
+ .of_match_table = mv_xor_dt_ids,
+ },
+};
+
+builtin_platform_driver(mv_xor_driver);
+
+/*
+MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>");
+MODULE_DESCRIPTION("DMA engine driver for Marvell's XOR engine");
+MODULE_LICENSE("GPL");
+*/