--- /dev/null
+/*
+ * offload engine driver for the Marvell XOR engine
+ * Copyright (C) 2007, 2008, Marvell International Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.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/platform_data/dma-mv_xor.h>
+
+#include "dmaengine.h"
+#include "mv_xor.h"
+
+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_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_clear_next_desc(struct mv_xor_desc_slot *desc)
+{
+ struct mv_xor_desc *hw_desc = desc->hw_desc;
+ hw_desc->phy_next_desc = 0;
+}
+
+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_xor_device_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_xor_device_clear_err_status(struct mv_xor_chan *chan)
+{
+ u32 val = 0xFFFF0000 >> (chan->idx * 16);
+ writel_relaxed(val, XOR_INTR_CAUSE(chan));
+}
+
+static void mv_set_mode(struct mv_xor_chan *chan,
+ enum dma_transaction_type type)
+{
+ u32 op_mode;
+ u32 config = readl_relaxed(XOR_CONFIG(chan));
+
+ switch (type) {
+ case DMA_XOR:
+ op_mode = XOR_OPERATION_MODE_XOR;
+ break;
+ case DMA_MEMCPY:
+ op_mode = XOR_OPERATION_MODE_MEMCPY;
+ break;
+ default:
+ dev_err(mv_chan_to_devp(chan),
+ "error: unsupported operation %d\n",
+ type);
+ BUG();
+ return;
+ }
+
+ 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));
+ chan->current_type = type;
+}
+
+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_xor_free_slots - flags descriptor slots for reuse
+ * @slot: Slot to free
+ * Caller must hold &mv_chan->lock while calling this function
+ */
+static void mv_xor_free_slots(struct mv_xor_chan *mv_chan,
+ struct mv_xor_desc_slot *slot)
+{
+ dev_dbg(mv_chan_to_devp(mv_chan), "%s %d slot %p\n",
+ __func__, __LINE__, slot);
+
+ slot->slot_used = 0;
+
+}
+
+/*
+ * mv_xor_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_xor_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_xor_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;
+
+ /* call the callback (must not sleep or submit new
+ * operations to this channel)
+ */
+ if (desc->async_tx.callback)
+ desc->async_tx.callback(
+ desc->async_tx.callback_param);
+
+ dma_descriptor_unmap(&desc->async_tx);
+ }
+
+ /* run dependent operations */
+ dma_run_dependencies(&desc->async_tx);
+
+ return cookie;
+}
+
+static int
+mv_xor_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,
+ completed_node) {
+
+ if (async_tx_test_ack(&iter->async_tx)) {
+ list_del(&iter->completed_node);
+ mv_xor_free_slots(mv_chan, iter);
+ }
+ }
+ return 0;
+}
+
+static int
+mv_xor_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);
+ list_del(&desc->chain_node);
+ /* 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_add_tail(&desc->completed_node, &mv_chan->completed_slots);
+ return 0;
+ }
+
+ mv_xor_free_slots(mv_chan, desc);
+ return 0;
+}
+
+/* This function must be called with the mv_xor_chan spinlock held */
+static void mv_xor_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 seen_current = 0;
+
+ 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_xor_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,
+ chain_node) {
+ prefetch(_iter);
+ prefetch(&_iter->async_tx);
+
+ /* do not advance past the current descriptor loaded into the
+ * hardware channel, subsequent descriptors are either in
+ * process or have not been submitted
+ */
+ if (seen_current)
+ break;
+
+ /* stop the search if we reach the current descriptor and the
+ * channel is busy
+ */
+ if (iter->async_tx.phys == current_desc) {
+ seen_current = 1;
+ if (busy)
+ break;
+ }
+
+ cookie = mv_xor_run_tx_complete_actions(iter, mv_chan, cookie);
+
+ if (mv_xor_clean_slot(iter, mv_chan))
+ break;
+ }
+
+ if ((busy == 0) && !list_empty(&mv_chan->chain)) {
+ struct mv_xor_desc_slot *chain_head;
+ chain_head = list_entry(mv_chan->chain.next,
+ struct mv_xor_desc_slot,
+ chain_node);
+
+ mv_xor_start_new_chain(mv_chan, chain_head);
+ }
+
+ if (cookie > 0)
+ mv_chan->dmachan.completed_cookie = cookie;
+}
+
+static void mv_xor_tasklet(unsigned long data)
+{
+ struct mv_xor_chan *chan = (struct mv_xor_chan *) data;
+
+ spin_lock_bh(&chan->lock);
+ mv_xor_slot_cleanup(chan);
+ spin_unlock_bh(&chan->lock);
+}
+
+static struct mv_xor_desc_slot *
+mv_xor_alloc_slot(struct mv_xor_chan *mv_chan)
+{
+ struct mv_xor_desc_slot *iter, *_iter;
+ int retry = 0;
+
+ /* start search from the last allocated descrtiptor
+ * if a contiguous allocation can not be found start searching
+ * from the beginning of the list
+ */
+retry:
+ if (retry == 0)
+ iter = mv_chan->last_used;
+ else
+ iter = list_entry(&mv_chan->all_slots,
+ struct mv_xor_desc_slot,
+ slot_node);
+
+ list_for_each_entry_safe_continue(
+ iter, _iter, &mv_chan->all_slots, slot_node) {
+
+ prefetch(_iter);
+ prefetch(&_iter->async_tx);
+ if (iter->slot_used) {
+ /* give up after finding the first busy slot
+ * on the second pass through the list
+ */
+ if (retry)
+ break;
+ continue;
+ }
+
+ /* pre-ack descriptor */
+ async_tx_ack(&iter->async_tx);
+
+ iter->slot_used = 1;
+ INIT_LIST_HEAD(&iter->chain_node);
+ iter->async_tx.cookie = -EBUSY;
+ mv_chan->last_used = iter;
+ mv_desc_clear_next_desc(iter);
+
+ return iter;
+
+ }
+ if (!retry++)
+ goto retry;
+
+ /* 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_add_tail(&sw_desc->chain_node, &mv_chan->chain);
+ else {
+ new_hw_chain = 0;
+
+ old_chain_tail = list_entry(mv_chan->chain.prev,
+ struct mv_xor_desc_slot,
+ chain_node);
+ list_add_tail(&sw_desc->chain_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_xor_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->chain_node);
+ INIT_LIST_HEAD(&slot->slot_node);
+ 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->slot_node, &mv_chan->all_slots);
+ spin_unlock_bh(&mv_chan->lock);
+ }
+
+ if (mv_chan->slots_allocated && !mv_chan->last_used)
+ mv_chan->last_used = list_entry(mv_chan->all_slots.next,
+ struct mv_xor_desc_slot,
+ slot_node);
+
+ dev_dbg(mv_chan_to_devp(mv_chan),
+ "allocated %d descriptor slots last_used: %p\n",
+ mv_chan->slots_allocated, mv_chan->last_used);
+
+ return mv_chan->slots_allocated ? : -ENOMEM;
+}
+
+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;
+
+ 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: %u dest %pad flags: %ld\n",
+ __func__, src_cnt, len, &dest, flags);
+
+ spin_lock_bh(&mv_chan->lock);
+ sw_desc = mv_xor_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);
+ while (src_cnt--)
+ mv_desc_set_src_addr(sw_desc, src_cnt, src[src_cnt]);
+ }
+ spin_unlock_bh(&mv_chan->lock);
+ 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_xor_slot_cleanup(mv_chan);
+
+ list_for_each_entry_safe(iter, _iter, &mv_chan->chain,
+ chain_node) {
+ in_use_descs++;
+ list_del(&iter->chain_node);
+ }
+ list_for_each_entry_safe(iter, _iter, &mv_chan->completed_slots,
+ completed_node) {
+ in_use_descs++;
+ list_del(&iter->completed_node);
+ }
+ list_for_each_entry_safe_reverse(
+ iter, _iter, &mv_chan->all_slots, slot_node) {
+ list_del(&iter->slot_node);
+ kfree(iter);
+ mv_chan->slots_allocated--;
+ }
+ mv_chan->last_used = NULL;
+
+ 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_xor_slot_cleanup(mv_chan);
+ spin_unlock_bh(&mv_chan->lock);
+
+ return dma_cookie_status(chan, cookie, txstate);
+}
+
+static void mv_dump_xor_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_xor_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_dump_xor_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_xor_err_interrupt_handler(chan, intr_cause);
+
+ tasklet_schedule(&chan->irq_tasklet);
+
+ mv_xor_device_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_xor_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(sizeof(u8) * PAGE_SIZE, GFP_KERNEL);
+ if (!src)
+ return -ENOMEM;
+
+ dest = kzalloc(sizeof(u8) * 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), 0,
+ 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), 0,
+ 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_xor_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;
+
+ dma_dev = &mv_chan->dmadev;
+
+ /*
+ * 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_writecombine(&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;
+ dma_dev->dev = &pdev->dev;
+
+ /* 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_init(&mv_chan->irq_tasklet, mv_xor_tasklet, (unsigned long)
+ mv_chan);
+
+ /* clear errors before enabling interrupts */
+ mv_xor_device_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);
+
+ mv_set_mode(mv_chan, DMA_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->all_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_xor_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_xor_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)\n",
+ 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 " : "");
+
+ dma_async_device_register(dma_dev);
+ 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));
+
+ 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 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;
+ 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);
+
+ /*
+ * (Re-)program MBUS remapping windows if we are asked to.
+ */
+ 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);
+
+ 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;
+
+ dma_cap_zero(cap_mask);
+ if (of_property_read_bool(np, "dmacap,memcpy"))
+ dma_cap_set(DMA_MEMCPY, cap_mask);
+ if (of_property_read_bool(np, "dmacap,xor"))
+ dma_cap_set(DMA_XOR, cap_mask);
+ if (of_property_read_bool(np, "dmacap,interrupt"))
+ 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 < MV_XOR_MAX_CHANNELS; i++) {
+ struct mv_xor_channel_data *cd;
+ struct mv_xor_chan *chan;
+ int irq;
+
+ cd = &pdata->channels[i];
+ if (!cd) {
+ ret = -ENODEV;
+ goto err_channel_add;
+ }
+
+ 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 int mv_xor_remove(struct platform_device *pdev)
+{
+ struct mv_xor_device *xordev = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) {
+ if (xordev->channels[i])
+ mv_xor_channel_remove(xordev->channels[i]);
+ }
+
+ if (!IS_ERR(xordev->clk)) {
+ clk_disable_unprepare(xordev->clk);
+ clk_put(xordev->clk);
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id mv_xor_dt_ids[] = {
+ { .compatible = "marvell,orion-xor", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mv_xor_dt_ids);
+#endif
+
+static struct platform_driver mv_xor_driver = {
+ .probe = mv_xor_probe,
+ .remove = mv_xor_remove,
+ .driver = {
+ .name = MV_XOR_NAME,
+ .of_match_table = of_match_ptr(mv_xor_dt_ids),
+ },
+};
+
+
+static int __init mv_xor_init(void)
+{
+ return platform_driver_register(&mv_xor_driver);
+}
+module_init(mv_xor_init);
+
+/* it's currently unsafe to unload this module */
+#if 0
+static void __exit mv_xor_exit(void)
+{
+ platform_driver_unregister(&mv_xor_driver);
+ return;
+}
+
+module_exit(mv_xor_exit);
+#endif
+
+MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>");
+MODULE_DESCRIPTION("DMA engine driver for Marvell's XOR engine");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff