[PATCH v4 2/4] dma: mv_xor_v2: new driver
Thomas Petazzoni
thomas.petazzoni at free-electrons.com
Thu Jun 16 05:28:34 PDT 2016
The new mv_xor_v2 driver supports the XOR engines found in the 64-bits
ARM from Marvell of the Armada 7K and Armada 8K family. This XOR
engine is a completely new hardware block, entirely different from the
one used on previous Marvell Armada platforms, which use the existing
mv_xor driver.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
---
drivers/dma/Kconfig | 14 +
drivers/dma/Makefile | 1 +
drivers/dma/mv_xor_v2.c | 879 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 894 insertions(+)
create mode 100644 drivers/dma/mv_xor_v2.c
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 8c98779..f6c46d0 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -339,6 +339,20 @@ config MV_XOR
---help---
Enable support for the Marvell XOR engine.
+config MV_XOR_V2
+ bool "Marvell XOR engine version 2 support "
+ depends on ARM64
+ select DMA_ENGINE
+ select DMA_ENGINE_RAID
+ select ASYNC_TX_ENABLE_CHANNEL_SWITCH
+ select GENERIC_MSI_IRQ_DOMAIN
+ ---help---
+ Enable support for the Marvell version 2 XOR engine.
+
+ This engine provides acceleration for copy, XOR and RAID6
+ operations, and is available on Marvell Armada 7K and 8K
+ platforms.
+
config MXS_DMA
bool "MXS DMA support"
depends on SOC_IMX23 || SOC_IMX28 || SOC_IMX6Q || SOC_IMX6UL
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 614f28b..e4dc9ca 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o
obj-$(CONFIG_MOXART_DMA) += moxart-dma.o
obj-$(CONFIG_MPC512X_DMA) += mpc512x_dma.o
obj-$(CONFIG_MV_XOR) += mv_xor.o
+obj-$(CONFIG_MV_XOR_V2) += mv_xor_v2.o
obj-$(CONFIG_MXS_DMA) += mxs-dma.o
obj-$(CONFIG_MX3_IPU) += ipu/
obj-$(CONFIG_NBPFAXI_DMA) += nbpfaxi.o
diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c
new file mode 100644
index 0000000..8320155
--- /dev/null
+++ b/drivers/dma/mv_xor_v2.c
@@ -0,0 +1,879 @@
+/*
+ * Copyright (C) 2015-2016 Marvell International Ltd.
+
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 2 of the
+ * License, or any later version.
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+#include "dmaengine.h"
+
+/* DMA Engine Registers */
+#define MV_XOR_V2_DMA_DESQ_BALR_OFF 0x000
+#define MV_XOR_V2_DMA_DESQ_BAHR_OFF 0x004
+#define MV_XOR_V2_DMA_DESQ_SIZE_OFF 0x008
+#define MV_XOR_V2_DMA_DESQ_DONE_OFF 0x00C
+#define MV_XOR_V2_DMA_DESQ_DONE_PENDING_MASK 0x7FFF
+#define MV_XOR_V2_DMA_DESQ_DONE_PENDING_SHIFT 0
+#define MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_MASK 0x1FFF
+#define MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_SHIFT 16
+#define MV_XOR_V2_DMA_DESQ_ARATTR_OFF 0x010
+#define MV_XOR_V2_DMA_DESQ_ATTR_CACHE_MASK 0x3F3F
+#define MV_XOR_V2_DMA_DESQ_ATTR_OUTER_SHAREABLE 0x202
+#define MV_XOR_V2_DMA_DESQ_ATTR_CACHEABLE 0x3C3C
+#define MV_XOR_V2_DMA_IMSG_CDAT_OFF 0x014
+#define MV_XOR_V2_DMA_IMSG_THRD_OFF 0x018
+#define MV_XOR_V2_DMA_IMSG_THRD_MASK 0x7FFF
+#define MV_XOR_V2_DMA_IMSG_THRD_SHIFT 0x0
+#define MV_XOR_V2_DMA_DESQ_AWATTR_OFF 0x01C
+ /* Same flags as MV_XOR_V2_DMA_DESQ_ARATTR_OFF */
+#define MV_XOR_V2_DMA_DESQ_ALLOC_OFF 0x04C
+#define MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_MASK 0xFFFF
+#define MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_SHIFT 16
+#define MV_XOR_V2_DMA_IMSG_BALR_OFF 0x050
+#define MV_XOR_V2_DMA_IMSG_BAHR_OFF 0x054
+#define MV_XOR_V2_DMA_DESQ_CTRL_OFF 0x100
+#define MV_XOR_V2_DMA_DESQ_CTRL_32B 1
+#define MV_XOR_V2_DMA_DESQ_CTRL_128B 7
+#define MV_XOR_V2_DMA_DESQ_STOP_OFF 0x800
+#define MV_XOR_V2_DMA_DESQ_DEALLOC_OFF 0x804
+#define MV_XOR_V2_DMA_DESQ_ADD_OFF 0x808
+
+/* XOR Global registers */
+#define MV_XOR_V2_GLOB_BW_CTRL 0x4
+#define MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_SHIFT 0
+#define MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_VAL 64
+#define MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_SHIFT 8
+#define MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_VAL 8
+#define MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_SHIFT 12
+#define MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_VAL 4
+#define MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_SHIFT 16
+#define MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_VAL 4
+#define MV_XOR_V2_GLOB_PAUSE 0x014
+#define MV_XOR_V2_GLOB_PAUSE_AXI_TIME_DIS_VAL 0x8
+#define MV_XOR_V2_GLOB_SYS_INT_CAUSE 0x200
+#define MV_XOR_V2_GLOB_SYS_INT_MASK 0x204
+#define MV_XOR_V2_GLOB_MEM_INT_CAUSE 0x220
+#define MV_XOR_V2_GLOB_MEM_INT_MASK 0x224
+
+#define MV_XOR_V2_MIN_DESC_SIZE 32
+#define MV_XOR_V2_EXT_DESC_SIZE 128
+
+#define MV_XOR_V2_DESC_RESERVED_SIZE 12
+#define MV_XOR_V2_DESC_BUFF_D_ADDR_SIZE 12
+
+#define MV_XOR_V2_CMD_LINE_NUM_MAX_D_BUF 8
+
+/*
+ * Descriptors queue size. With 32 bytes descriptors, up to 2^14
+ * descriptors are allowed, with 128 bytes descriptors, up to 2^12
+ * descriptors are allowed. This driver uses 128 bytes descriptors,
+ * but experimentation has shown that a set of 1024 descriptors is
+ * sufficient to reach a good level of performance.
+ */
+#define MV_XOR_V2_DESC_NUM 1024
+
+/**
+ * struct mv_xor_v2_descriptor - DMA HW descriptor
+ * @desc_id: used by S/W and is not affected by H/W.
+ * @flags: error and status flags
+ * @crc32_result: CRC32 calculation result
+ * @desc_ctrl: operation mode and control flags
+ * @buff_size: amount of bytes to be processed
+ * @fill_pattern_src_addr: Fill-Pattern or Source-Address and
+ * AW-Attributes
+ * @data_buff_addr: Source (and might be RAID6 destination)
+ * addresses of data buffers in RAID5 and RAID6
+ * @reserved: reserved
+ */
+struct mv_xor_v2_descriptor {
+ u16 desc_id;
+ u16 flags;
+ u32 crc32_result;
+ u32 desc_ctrl;
+
+ /* Definitions for desc_ctrl */
+#define DESC_NUM_ACTIVE_D_BUF_SHIFT 22
+#define DESC_OP_MODE_SHIFT 28
+#define DESC_OP_MODE_NOP 0 /* Idle operation */
+#define DESC_OP_MODE_MEMCPY 1 /* Pure-DMA operation */
+#define DESC_OP_MODE_MEMSET 2 /* Mem-Fill operation */
+#define DESC_OP_MODE_MEMINIT 3 /* Mem-Init operation */
+#define DESC_OP_MODE_MEM_COMPARE 4 /* Mem-Compare operation */
+#define DESC_OP_MODE_CRC32 5 /* CRC32 calculation */
+#define DESC_OP_MODE_XOR 6 /* RAID5 (XOR) operation */
+#define DESC_OP_MODE_RAID6 7 /* RAID6 P&Q-generation */
+#define DESC_OP_MODE_RAID6_REC 8 /* RAID6 Recovery */
+#define DESC_Q_BUFFER_ENABLE BIT(16)
+#define DESC_P_BUFFER_ENABLE BIT(17)
+#define DESC_IOD BIT(27)
+
+ u32 buff_size;
+ u32 fill_pattern_src_addr[4];
+ u32 data_buff_addr[MV_XOR_V2_DESC_BUFF_D_ADDR_SIZE];
+ u32 reserved[MV_XOR_V2_DESC_RESERVED_SIZE];
+};
+
+/**
+ * struct mv_xor_v2_device - implements a xor device
+ * @lock: lock for the engine
+ * @dma_base: memory mapped DMA register base
+ * @glob_base: memory mapped global register base
+ * @irq_tasklet:
+ * @free_sw_desc: linked list of free SW descriptors
+ * @dmadev: dma device
+ * @dmachan: dma channel
+ * @hw_desq: HW descriptors queue
+ * @hw_desq_virt: virtual address of DESCQ
+ * @sw_desq: SW descriptors queue
+ * @desc_size: HW descriptor size
+ * @npendings: number of pending descriptors (for which tx_submit has
+ * been called, but not yet issue_pending)
+ */
+struct mv_xor_v2_device {
+ spinlock_t lock;
+ void __iomem *dma_base;
+ void __iomem *glob_base;
+ struct clk *clk;
+ struct tasklet_struct irq_tasklet;
+ struct list_head free_sw_desc;
+ struct dma_device dmadev;
+ struct dma_chan dmachan;
+ dma_addr_t hw_desq;
+ struct mv_xor_v2_descriptor *hw_desq_virt;
+ struct mv_xor_v2_sw_desc *sw_desq;
+ int desc_size;
+ unsigned int npendings;
+};
+
+/**
+ * struct mv_xor_v2_sw_desc - implements a xor SW descriptor
+ * @idx: descriptor index
+ * @async_tx: support for the async_tx api
+ * @hw_desc: assosiated HW descriptor
+ * @free_list: node of the free SW descriprots list
+*/
+struct mv_xor_v2_sw_desc {
+ int idx;
+ struct dma_async_tx_descriptor async_tx;
+ struct mv_xor_v2_descriptor hw_desc;
+ struct list_head free_list;
+};
+
+/*
+ * Fill the data buffers to a HW descriptor
+ */
+static void mv_xor_v2_set_data_buffers(struct mv_xor_v2_device *xor_dev,
+ struct mv_xor_v2_descriptor *desc,
+ dma_addr_t src, int index)
+{
+ int arr_index = ((index >> 1) * 3);
+
+ /*
+ * Fill the buffer's addresses to the descriptor.
+ *
+ * The format of the buffers address for 2 sequential buffers
+ * X and X + 1:
+ *
+ * First word: Buffer-DX-Address-Low[31:0]
+ * Second word: Buffer-DX+1-Address-Low[31:0]
+ * Third word: DX+1-Buffer-Address-High[47:32] [31:16]
+ * DX-Buffer-Address-High[47:32] [15:0]
+ */
+ if ((index & 0x1) == 0) {
+ desc->data_buff_addr[arr_index] = lower_32_bits(src);
+
+ desc->data_buff_addr[arr_index + 2] &= ~0xFFFF;
+ desc->data_buff_addr[arr_index + 2] |=
+ upper_32_bits(src) & 0xFFFF;
+ } else {
+ desc->data_buff_addr[arr_index + 1] =
+ lower_32_bits(src);
+
+ desc->data_buff_addr[arr_index + 2] &= ~0xFFFF0000;
+ desc->data_buff_addr[arr_index + 2] |=
+ (upper_32_bits(src) & 0xFFFF) << 16;
+ }
+}
+
+/*
+ * Return the next available index in the DESQ.
+ */
+static int mv_xor_v2_get_desq_write_ptr(struct mv_xor_v2_device *xor_dev)
+{
+ /* read the index for the next available descriptor in the DESQ */
+ u32 reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ALLOC_OFF);
+
+ return ((reg >> MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_SHIFT)
+ & MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_MASK);
+}
+
+/*
+ * notify the engine of new descriptors, and update the available index.
+ */
+static void mv_xor_v2_add_desc_to_desq(struct mv_xor_v2_device *xor_dev,
+ int num_of_desc)
+{
+ /* write the number of new descriptors in the DESQ. */
+ writel(num_of_desc, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ADD_OFF);
+}
+
+/*
+ * free HW descriptors
+ */
+static void mv_xor_v2_free_desc_from_desq(struct mv_xor_v2_device *xor_dev,
+ int num_of_desc)
+{
+ /* write the number of new descriptors in the DESQ. */
+ writel(num_of_desc, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_DEALLOC_OFF);
+}
+
+/*
+ * Set descriptor size
+ * Return the HW descriptor size in bytes
+ */
+static int mv_xor_v2_set_desc_size(struct mv_xor_v2_device *xor_dev)
+{
+ writel(MV_XOR_V2_DMA_DESQ_CTRL_128B,
+ xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_CTRL_OFF);
+
+ return MV_XOR_V2_EXT_DESC_SIZE;
+}
+
+/*
+ * Set the IMSG threshold
+ */
+static inline
+void mv_xor_v2_set_imsg_thrd(struct mv_xor_v2_device *xor_dev, int thrd_val)
+{
+ u32 reg;
+
+ reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF);
+
+ reg &= (~MV_XOR_V2_DMA_IMSG_THRD_MASK << MV_XOR_V2_DMA_IMSG_THRD_SHIFT);
+ reg |= (thrd_val << MV_XOR_V2_DMA_IMSG_THRD_SHIFT);
+
+ writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF);
+}
+
+static irqreturn_t mv_xor_v2_interrupt_handler(int irq, void *data)
+{
+ struct mv_xor_v2_device *xor_dev = data;
+ unsigned int ndescs;
+ u32 reg;
+
+ reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_DONE_OFF);
+
+ ndescs = ((reg >> MV_XOR_V2_DMA_DESQ_DONE_PENDING_SHIFT) &
+ MV_XOR_V2_DMA_DESQ_DONE_PENDING_MASK);
+
+ /* No descriptors to process */
+ if (!ndescs)
+ return IRQ_NONE;
+
+ /*
+ * Update IMSG threshold, to disable new IMSG interrupts until
+ * end of the tasklet
+ */
+ mv_xor_v2_set_imsg_thrd(xor_dev, MV_XOR_V2_DESC_NUM);
+
+ /* schedule a tasklet to handle descriptors callbacks */
+ tasklet_schedule(&xor_dev->irq_tasklet);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * submit a descriptor to the DMA engine
+ */
+static dma_cookie_t
+mv_xor_v2_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ int desq_ptr;
+ void *dest_hw_desc;
+ dma_cookie_t cookie;
+ struct mv_xor_v2_sw_desc *sw_desc =
+ container_of(tx, struct mv_xor_v2_sw_desc, async_tx);
+ struct mv_xor_v2_device *xor_dev =
+ container_of(tx->chan, struct mv_xor_v2_device, dmachan);
+
+ dev_dbg(xor_dev->dmadev.dev,
+ "%s sw_desc %p: async_tx %p\n",
+ __func__, sw_desc, &sw_desc->async_tx);
+
+ /* assign coookie */
+ spin_lock_bh(&xor_dev->lock);
+ cookie = dma_cookie_assign(tx);
+
+ /* get the next available slot in the DESQ */
+ desq_ptr = mv_xor_v2_get_desq_write_ptr(xor_dev);
+
+ /* copy the HW descriptor from the SW descriptor to the DESQ */
+ dest_hw_desc = xor_dev->hw_desq_virt + desq_ptr;
+
+ memcpy(dest_hw_desc, &sw_desc->hw_desc, xor_dev->desc_size);
+
+ xor_dev->npendings++;
+
+ spin_unlock_bh(&xor_dev->lock);
+
+ return cookie;
+}
+
+/*
+ * Prepare a SW descriptor
+ */
+static struct mv_xor_v2_sw_desc *
+mv_xor_v2_prep_sw_desc(struct mv_xor_v2_device *xor_dev)
+{
+ struct mv_xor_v2_sw_desc *sw_desc;
+
+ /* Lock the channel */
+ spin_lock_bh(&xor_dev->lock);
+
+ if (list_empty(&xor_dev->free_sw_desc)) {
+ spin_unlock_bh(&xor_dev->lock);
+ /* schedule tasklet to free some descriptors */
+ tasklet_schedule(&xor_dev->irq_tasklet);
+ return NULL;
+ }
+
+ /* get a free SW descriptor from the SW DESQ */
+ sw_desc = list_first_entry(&xor_dev->free_sw_desc,
+ struct mv_xor_v2_sw_desc, free_list);
+ list_del(&sw_desc->free_list);
+
+ /* Release the channel */
+ spin_unlock_bh(&xor_dev->lock);
+
+ /* set the async tx descriptor */
+ dma_async_tx_descriptor_init(&sw_desc->async_tx, &xor_dev->dmachan);
+ sw_desc->async_tx.tx_submit = mv_xor_v2_tx_submit;
+ async_tx_ack(&sw_desc->async_tx);
+
+ return sw_desc;
+}
+
+/*
+ * Prepare a HW descriptor for a memcpy operation
+ */
+static struct dma_async_tx_descriptor *
+mv_xor_v2_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest,
+ dma_addr_t src, size_t len, unsigned long flags)
+{
+ struct mv_xor_v2_sw_desc *sw_desc;
+ struct mv_xor_v2_descriptor *hw_descriptor;
+ struct mv_xor_v2_device *xor_dev;
+
+ xor_dev = container_of(chan, struct mv_xor_v2_device, dmachan);
+
+ dev_dbg(xor_dev->dmadev.dev,
+ "%s len: %zu src %pad dest %pad flags: %ld\n",
+ __func__, len, &src, &dest, flags);
+
+ sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
+
+ sw_desc->async_tx.flags = flags;
+
+ /* set the HW descriptor */
+ hw_descriptor = &sw_desc->hw_desc;
+
+ /* save the SW descriptor ID to restore when operation is done */
+ hw_descriptor->desc_id = sw_desc->idx;
+
+ /* Set the MEMCPY control word */
+ hw_descriptor->desc_ctrl =
+ DESC_OP_MODE_MEMCPY << DESC_OP_MODE_SHIFT;
+
+ if (flags & DMA_PREP_INTERRUPT)
+ hw_descriptor->desc_ctrl |= DESC_IOD;
+
+ /* Set source address */
+ hw_descriptor->fill_pattern_src_addr[0] = lower_32_bits(src);
+ hw_descriptor->fill_pattern_src_addr[1] =
+ upper_32_bits(src) & 0xFFFF;
+
+ /* Set Destination address */
+ hw_descriptor->fill_pattern_src_addr[2] = lower_32_bits(dest);
+ hw_descriptor->fill_pattern_src_addr[3] =
+ upper_32_bits(dest) & 0xFFFF;
+
+ /* Set buffers size */
+ hw_descriptor->buff_size = len;
+
+ /* return the async tx descriptor */
+ return &sw_desc->async_tx;
+}
+
+/*
+ * Prepare a HW descriptor for a XOR operation
+ */
+static struct dma_async_tx_descriptor *
+mv_xor_v2_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_v2_sw_desc *sw_desc;
+ struct mv_xor_v2_descriptor *hw_descriptor;
+ struct mv_xor_v2_device *xor_dev =
+ container_of(chan, struct mv_xor_v2_device, dmachan);
+ int i;
+
+ if (src_cnt > MV_XOR_V2_CMD_LINE_NUM_MAX_D_BUF || src_cnt < 1)
+ return NULL;
+
+ dev_dbg(xor_dev->dmadev.dev,
+ "%s src_cnt: %d len: %zu dest %pad flags: %ld\n",
+ __func__, src_cnt, len, &dest, flags);
+
+ sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
+
+ sw_desc->async_tx.flags = flags;
+
+ /* set the HW descriptor */
+ hw_descriptor = &sw_desc->hw_desc;
+
+ /* save the SW descriptor ID to restore when operation is done */
+ hw_descriptor->desc_id = sw_desc->idx;
+
+ /* Set the XOR control word */
+ hw_descriptor->desc_ctrl =
+ DESC_OP_MODE_XOR << DESC_OP_MODE_SHIFT;
+ hw_descriptor->desc_ctrl |= DESC_P_BUFFER_ENABLE;
+
+ if (flags & DMA_PREP_INTERRUPT)
+ hw_descriptor->desc_ctrl |= DESC_IOD;
+
+ /* Set the data buffers */
+ for (i = 0; i < src_cnt; i++)
+ mv_xor_v2_set_data_buffers(xor_dev, hw_descriptor, src[i], i);
+
+ hw_descriptor->desc_ctrl |=
+ src_cnt << DESC_NUM_ACTIVE_D_BUF_SHIFT;
+
+ /* Set Destination address */
+ hw_descriptor->fill_pattern_src_addr[2] = lower_32_bits(dest);
+ hw_descriptor->fill_pattern_src_addr[3] =
+ upper_32_bits(dest) & 0xFFFF;
+
+ /* Set buffers size */
+ hw_descriptor->buff_size = len;
+
+ /* return the async tx descriptor */
+ return &sw_desc->async_tx;
+}
+
+/*
+ * Prepare a HW descriptor for interrupt operation.
+ */
+static struct dma_async_tx_descriptor *
+mv_xor_v2_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
+{
+ struct mv_xor_v2_sw_desc *sw_desc;
+ struct mv_xor_v2_descriptor *hw_descriptor;
+ struct mv_xor_v2_device *xor_dev =
+ container_of(chan, struct mv_xor_v2_device, dmachan);
+
+ sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
+
+ /* set the HW descriptor */
+ hw_descriptor = &sw_desc->hw_desc;
+
+ /* save the SW descriptor ID to restore when operation is done */
+ hw_descriptor->desc_id = sw_desc->idx;
+
+ /* Set the INTERRUPT control word */
+ hw_descriptor->desc_ctrl =
+ DESC_OP_MODE_NOP << DESC_OP_MODE_SHIFT;
+ hw_descriptor->desc_ctrl |= DESC_IOD;
+
+ /* return the async tx descriptor */
+ return &sw_desc->async_tx;
+}
+
+/*
+ * push pending transactions to hardware
+ */
+static void mv_xor_v2_issue_pending(struct dma_chan *chan)
+{
+ struct mv_xor_v2_device *xor_dev =
+ container_of(chan, struct mv_xor_v2_device, dmachan);
+
+ spin_lock_bh(&xor_dev->lock);
+
+ /*
+ * update the engine with the number of descriptors to
+ * process
+ */
+ mv_xor_v2_add_desc_to_desq(xor_dev, xor_dev->npendings);
+ xor_dev->npendings = 0;
+
+ /* Activate the channel */
+ writel(0, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_STOP_OFF);
+
+ spin_unlock_bh(&xor_dev->lock);
+}
+
+static inline
+int mv_xor_v2_get_pending_params(struct mv_xor_v2_device *xor_dev,
+ int *pending_ptr)
+{
+ u32 reg;
+
+ reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_DONE_OFF);
+
+ /* get the next pending descriptor index */
+ *pending_ptr = ((reg >> MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_SHIFT) &
+ MV_XOR_V2_DMA_DESQ_DONE_READ_PTR_MASK);
+
+ /* get the number of descriptors pending handle */
+ return ((reg >> MV_XOR_V2_DMA_DESQ_DONE_PENDING_SHIFT) &
+ MV_XOR_V2_DMA_DESQ_DONE_PENDING_MASK);
+}
+
+/*
+ * handle the descriptors after HW process
+ */
+static void mv_xor_v2_tasklet(unsigned long data)
+{
+ struct mv_xor_v2_device *xor_dev = (struct mv_xor_v2_device *) data;
+ int pending_ptr, num_of_pending, i;
+ struct mv_xor_v2_descriptor *next_pending_hw_desc = NULL;
+ struct mv_xor_v2_sw_desc *next_pending_sw_desc = NULL;
+
+ dev_dbg(xor_dev->dmadev.dev, "%s %d\n", __func__, __LINE__);
+
+ /* get the pending descriptors parameters */
+ num_of_pending = mv_xor_v2_get_pending_params(xor_dev, &pending_ptr);
+
+ /* next HW descriptor */
+ next_pending_hw_desc = xor_dev->hw_desq_virt + pending_ptr;
+
+ /* loop over free descriptors */
+ for (i = 0; i < num_of_pending; i++) {
+
+ if (pending_ptr > MV_XOR_V2_DESC_NUM)
+ pending_ptr = 0;
+
+ if (next_pending_sw_desc != NULL)
+ next_pending_hw_desc++;
+
+ /* get the SW descriptor related to the HW descriptor */
+ next_pending_sw_desc =
+ &xor_dev->sw_desq[next_pending_hw_desc->desc_id];
+
+ /* call the callback */
+ if (next_pending_sw_desc->async_tx.cookie > 0) {
+ /*
+ * update the channel's completed cookie - no
+ * lock is required the IMSG threshold provide
+ * the locking
+ */
+ dma_cookie_complete(&next_pending_sw_desc->async_tx);
+
+ if (next_pending_sw_desc->async_tx.callback)
+ next_pending_sw_desc->async_tx.callback(
+ next_pending_sw_desc->async_tx.callback_param);
+
+ dma_descriptor_unmap(&next_pending_sw_desc->async_tx);
+ }
+
+ dma_run_dependencies(&next_pending_sw_desc->async_tx);
+
+ /* Lock the channel */
+ spin_lock_bh(&xor_dev->lock);
+
+ /* add the SW descriptor to the free descriptors list */
+ list_add(&next_pending_sw_desc->free_list,
+ &xor_dev->free_sw_desc);
+
+ /* Release the channel */
+ spin_unlock_bh(&xor_dev->lock);
+
+ /* increment the next descriptor */
+ pending_ptr++;
+ }
+
+ if (num_of_pending != 0) {
+ /* free the descriptores */
+ mv_xor_v2_free_desc_from_desq(xor_dev, num_of_pending);
+ }
+
+ /* Update IMSG threshold, to enable new IMSG interrupts */
+ mv_xor_v2_set_imsg_thrd(xor_dev, 0);
+}
+
+/*
+ * Set DMA Interrupt-message (IMSG) parameters
+ */
+static void mv_xor_v2_set_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+ struct mv_xor_v2_device *xor_dev = dev_get_drvdata(desc->dev);
+
+ writel(msg->address_lo,
+ xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_BALR_OFF);
+ writel(msg->address_hi & 0xFFFF,
+ xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_BAHR_OFF);
+ writel(msg->data,
+ xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_CDAT_OFF);
+}
+
+static int mv_xor_v2_descq_init(struct mv_xor_v2_device *xor_dev)
+{
+ u32 reg;
+
+ /* write the DESQ size to the DMA engine */
+ writel(MV_XOR_V2_DESC_NUM,
+ xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_SIZE_OFF);
+
+ /* write the DESQ address to the DMA enngine*/
+ writel(xor_dev->hw_desq & 0xFFFFFFFF,
+ xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_BALR_OFF);
+ writel((xor_dev->hw_desq & 0xFFFF00000000) >> 32,
+ xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_BAHR_OFF);
+
+ /* enable the DMA engine */
+ writel(0, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_STOP_OFF);
+
+ /*
+ * This is a temporary solution, until we activate the
+ * SMMU. Set the attributes for reading & writing data buffers
+ * & descriptors to:
+ *
+ * - OuterShareable - Snoops will be performed on CPU caches
+ * - Enable cacheable - Bufferable, Modifiable, Other Allocate
+ * and Allocate
+ */
+ reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ARATTR_OFF);
+ reg &= ~MV_XOR_V2_DMA_DESQ_ATTR_CACHE_MASK;
+ reg |= MV_XOR_V2_DMA_DESQ_ATTR_OUTER_SHAREABLE |
+ MV_XOR_V2_DMA_DESQ_ATTR_CACHEABLE;
+ writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ARATTR_OFF);
+
+ reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_AWATTR_OFF);
+ reg &= ~MV_XOR_V2_DMA_DESQ_ATTR_CACHE_MASK;
+ reg |= MV_XOR_V2_DMA_DESQ_ATTR_OUTER_SHAREABLE |
+ MV_XOR_V2_DMA_DESQ_ATTR_CACHEABLE;
+ writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_AWATTR_OFF);
+
+ /* BW CTRL - set values to optimize the XOR performance:
+ *
+ * - Set WrBurstLen & RdBurstLen - the unit will issue
+ * maximum of 256B write/read transactions.
+ * - Limit the number of outstanding write & read data
+ * (OBB/IBB) requests to the maximal value.
+ */
+ reg = ((MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_VAL <<
+ MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_RD_SHIFT) |
+ (MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_VAL <<
+ MV_XOR_V2_GLOB_BW_CTRL_NUM_OSTD_WR_SHIFT) |
+ (MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_VAL <<
+ MV_XOR_V2_GLOB_BW_CTRL_RD_BURST_LEN_SHIFT) |
+ (MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_VAL <<
+ MV_XOR_V2_GLOB_BW_CTRL_WR_BURST_LEN_SHIFT));
+ writel(reg, xor_dev->glob_base + MV_XOR_V2_GLOB_BW_CTRL);
+
+ /* Disable the AXI timer feature */
+ reg = readl(xor_dev->glob_base + MV_XOR_V2_GLOB_PAUSE);
+ reg |= MV_XOR_V2_GLOB_PAUSE_AXI_TIME_DIS_VAL;
+ writel(reg, xor_dev->glob_base + MV_XOR_V2_GLOB_PAUSE);
+
+ return 0;
+}
+
+static int mv_xor_v2_probe(struct platform_device *pdev)
+{
+ struct mv_xor_v2_device *xor_dev;
+ struct resource *res;
+ int i, ret = 0;
+ struct dma_device *dma_dev;
+ struct mv_xor_v2_sw_desc *sw_desc;
+ struct msi_desc *msi_desc;
+
+ BUILD_BUG_ON(sizeof(struct mv_xor_v2_descriptor) !=
+ MV_XOR_V2_EXT_DESC_SIZE);
+
+ xor_dev = devm_kzalloc(&pdev->dev, sizeof(*xor_dev), GFP_KERNEL);
+ if (!xor_dev)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ xor_dev->dma_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(xor_dev->dma_base))
+ return PTR_ERR(xor_dev->dma_base);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ xor_dev->glob_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(xor_dev->glob_base))
+ return PTR_ERR(xor_dev->glob_base);
+
+ platform_set_drvdata(pdev, xor_dev);
+
+ xor_dev->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(xor_dev->clk) && PTR_ERR(xor_dev->clk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+ if (!IS_ERR(xor_dev->clk)) {
+ ret = clk_prepare_enable(xor_dev->clk);
+ if (ret)
+ return ret;
+ }
+
+ ret = platform_msi_domain_alloc_irqs(&pdev->dev, 1,
+ mv_xor_v2_set_msi_msg);
+ if (ret)
+ goto disable_clk;
+
+ msi_desc = first_msi_entry(&pdev->dev);
+ if (!msi_desc)
+ goto free_msi_irqs;
+
+ ret = devm_request_irq(&pdev->dev, msi_desc->irq,
+ mv_xor_v2_interrupt_handler, 0,
+ dev_name(&pdev->dev), xor_dev);
+ if (ret)
+ goto free_msi_irqs;
+
+ tasklet_init(&xor_dev->irq_tasklet, mv_xor_v2_tasklet,
+ (unsigned long) xor_dev);
+
+ xor_dev->desc_size = mv_xor_v2_set_desc_size(xor_dev);
+
+ dma_cookie_init(&xor_dev->dmachan);
+
+ /*
+ * allocate coherent memory for hardware descriptors
+ * note: writecombine gives slightly better performance, but
+ * requires that we explicitly flush the writes
+ */
+ xor_dev->hw_desq_virt =
+ dma_alloc_coherent(&pdev->dev,
+ xor_dev->desc_size * MV_XOR_V2_DESC_NUM,
+ &xor_dev->hw_desq, GFP_KERNEL);
+ if (!xor_dev->hw_desq_virt) {
+ ret = -ENOMEM;
+ goto free_msi_irqs;
+ }
+
+ /* alloc memory for the SW descriptors */
+ xor_dev->sw_desq = devm_kzalloc(&pdev->dev, sizeof(*sw_desc) *
+ MV_XOR_V2_DESC_NUM, GFP_KERNEL);
+ if (!xor_dev->sw_desq) {
+ ret = -ENOMEM;
+ goto free_hw_desq;
+ }
+
+ spin_lock_init(&xor_dev->lock);
+
+ /* init the free SW descriptors list */
+ INIT_LIST_HEAD(&xor_dev->free_sw_desc);
+
+ /* add all SW descriptors to the free list */
+ for (i = 0; i < MV_XOR_V2_DESC_NUM; i++) {
+ xor_dev->sw_desq[i].idx = i;
+ list_add(&xor_dev->sw_desq[i].free_list,
+ &xor_dev->free_sw_desc);
+ }
+
+ dma_dev = &xor_dev->dmadev;
+
+ /* set DMA capabilities */
+ dma_cap_zero(dma_dev->cap_mask);
+ dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
+ dma_cap_set(DMA_XOR, dma_dev->cap_mask);
+ dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask);
+
+ /* init dma link list */
+ INIT_LIST_HEAD(&dma_dev->channels);
+
+ /* set base routines */
+ dma_dev->device_tx_status = dma_cookie_status;
+ dma_dev->device_issue_pending = mv_xor_v2_issue_pending;
+ dma_dev->dev = &pdev->dev;
+
+ dma_dev->device_prep_dma_memcpy = mv_xor_v2_prep_dma_memcpy;
+ dma_dev->device_prep_dma_interrupt = mv_xor_v2_prep_dma_interrupt;
+ dma_dev->max_xor = 8;
+ dma_dev->device_prep_dma_xor = mv_xor_v2_prep_dma_xor;
+
+ xor_dev->dmachan.device = dma_dev;
+
+ list_add_tail(&xor_dev->dmachan.device_node,
+ &dma_dev->channels);
+
+ mv_xor_v2_descq_init(xor_dev);
+
+ ret = dma_async_device_register(dma_dev);
+ if (ret)
+ goto free_hw_desq;
+
+ dev_notice(&pdev->dev, "Marvell Version 2 XOR driver\n");
+
+ return 0;
+
+free_hw_desq:
+ dma_free_coherent(&pdev->dev,
+ xor_dev->desc_size * MV_XOR_V2_DESC_NUM,
+ xor_dev->hw_desq_virt, xor_dev->hw_desq);
+free_msi_irqs:
+ platform_msi_domain_free_irqs(&pdev->dev);
+disable_clk:
+ if (!IS_ERR(xor_dev->clk))
+ clk_disable_unprepare(xor_dev->clk);
+ return ret;
+}
+
+static int mv_xor_v2_remove(struct platform_device *pdev)
+{
+ struct mv_xor_v2_device *xor_dev = platform_get_drvdata(pdev);
+
+ dma_async_device_unregister(&xor_dev->dmadev);
+
+ dma_free_coherent(&pdev->dev,
+ xor_dev->desc_size * MV_XOR_V2_DESC_NUM,
+ xor_dev->hw_desq_virt, xor_dev->hw_desq);
+
+ platform_msi_domain_free_irqs(&pdev->dev);
+
+ clk_disable_unprepare(xor_dev->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id mv_xor_v2_dt_ids[] = {
+ { .compatible = "marvell,xor-v2", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mv_xor_v2_dt_ids);
+#endif
+
+static struct platform_driver mv_xor_v2_driver = {
+ .probe = mv_xor_v2_probe,
+ .remove = mv_xor_v2_remove,
+ .driver = {
+ .name = "mv_xor_v2",
+ .of_match_table = of_match_ptr(mv_xor_v2_dt_ids),
+ },
+};
+
+module_platform_driver(mv_xor_v2_driver);
+
+MODULE_DESCRIPTION("DMA engine driver for Marvell's Version 2 of XOR engine");
+MODULE_LICENSE("GPL");
+
--
2.7.4
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