@@ -20734,6 +20734,12 @@ S: Supported
F: include/net/switchdev.h
F: net/switchdev/
+SWITCHTEC DMA DRIVER
+M: Kelvin Cao <kelvin.cao@microchip.com>
+L: dmaengine@vger.kernel.org
+S: Maintained
+F: drivers/dma/switchtec_dma.c
+
SY8106A REGULATOR DRIVER
M: Icenowy Zheng <icenowy@aosc.io>
S: Maintained
@@ -594,6 +594,15 @@ config SPRD_DMA
help
Enable support for the on-chip DMA controller on Spreadtrum platform.
+config SWITCHTEC_DMA
+ tristate "Switchtec PSX/PFX Switch DMA Engine Support"
+ depends on PCI
+ select DMA_ENGINE
+ help
+ Some Switchtec PSX/PFX PCIe Switches support additional DMA engines.
+ These are exposed via an extra function on the switch's upstream
+ port.
+
config TXX9_DMAC
tristate "Toshiba TXx9 SoC DMA support"
depends on MACH_TX49XX
@@ -71,6 +71,7 @@ obj-$(CONFIG_STM32_DMA) += stm32-dma.o
obj-$(CONFIG_STM32_DMAMUX) += stm32-dmamux.o
obj-$(CONFIG_STM32_MDMA) += stm32-mdma.o
obj-$(CONFIG_SPRD_DMA) += sprd-dma.o
+obj-$(CONFIG_SWITCHTEC_DMA) += switchtec_dma.o
obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o
obj-$(CONFIG_TEGRA186_GPC_DMA) += tegra186-gpc-dma.o
obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o
new file mode 100644
@@ -0,0 +1,1522 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip Switchtec(tm) DMA Controller Driver
+ * Copyright (c) 2023, Kelvin Cao <kelvin.cao@microchip.com>
+ * Copyright (c) 2023, Microchip Corporation
+ */
+
+#include <linux/circ_buf.h>
+#include <linux/dmaengine.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+
+#include "dmaengine.h"
+
+MODULE_DESCRIPTION("Switchtec PCIe Switch DMA Engine");
+MODULE_VERSION("0.1");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Kelvin Cao");
+
+#define SWITCHTEC_DMAC_CHAN_CTRL_OFFSET 0x1000
+#define SWITCHTEC_DMAC_CHAN_CFG_STS_OFFSET 0x160000
+
+#define SWITCHTEC_DMA_CHAN_HW_REGS_SIZE 0x1000
+#define SWITCHTEC_DMA_CHAN_FW_REGS_SIZE 0x80
+
+#define SWITCHTEC_REG_CAP 0x80
+#define SWITCHTEC_REG_CHAN_CNT 0x84
+#define SWITCHTEC_REG_TAG_LIMIT 0x90
+#define SWITCHTEC_REG_CHAN_STS_VEC 0x94
+#define SWITCHTEC_REG_SE_BUF_CNT 0x98
+#define SWITCHTEC_REG_SE_BUF_BASE 0x9a
+
+#define SWITCHTEC_DESC_MAX_SIZE 0x100000
+
+#define SWITCHTEC_CHAN_CTRL_PAUSE BIT(0)
+#define SWITCHTEC_CHAN_CTRL_HALT BIT(1)
+#define SWITCHTEC_CHAN_CTRL_RESET BIT(2)
+#define SWITCHTEC_CHAN_CTRL_ERR_PAUSE BIT(3)
+
+#define SWITCHTEC_CHAN_STS_PAUSED BIT(9)
+#define SWITCHTEC_CHAN_STS_HALTED BIT(10)
+#define SWITCHTEC_CHAN_STS_PAUSED_MASK GENMASK(29, 13)
+
+static const char * const channel_status_str[] = {
+ [13] = "received a VDM with length error status",
+ [14] = "received a VDM or Cpl with Unsupported Request error status",
+ [15] = "received a VDM or Cpl with Completion Abort error status",
+ [16] = "received a VDM with ECRC error status",
+ [17] = "received a VDM with EP error status",
+ [18] = "received a VDM with Reserved Cpl error status",
+ [19] = "received only part of split SE CplD",
+ [20] = "the ISP_DMAC detected a Completion Time Out",
+ [21] = "received a Cpl with Unsupported Request status",
+ [22] = "received a Cpl with Completion Abort status",
+ [23] = "received a Cpl with a reserved status",
+ [24] = "received a TLP with ECRC error status in its metadata",
+ [25] = "received a TLP with the EP bit set in the header",
+ [26] = "the ISP_DMAC tried to process a SE with an invalid Connection ID",
+ [27] = "the ISP_DMAC tried to process a SE with an invalid Remote Host interrupt",
+ [28] = "a reserved opcode was detected in an SE",
+ [29] = "received a SE Cpl with error status",
+};
+
+struct chan_hw_regs {
+ u16 cq_head;
+ u16 rsvd1;
+ u16 sq_tail;
+ u16 rsvd2;
+ u8 ctrl;
+ u8 rsvd3[3];
+ u16 status;
+ u16 rsvd4;
+};
+
+enum {
+ PERF_BURST_SCALE = 0x1,
+ PERF_BURST_SIZE = 0x6,
+ PERF_INTERVAL = 0x0,
+ PERF_MRRS = 0x3,
+ PERF_ARB_WEIGHT = 0x1,
+};
+
+enum {
+ PERF_BURST_SCALE_SHIFT = 0x2,
+ PERF_BURST_SCALE_MASK = 0x3,
+ PERF_MRRS_SHIFT = 0x4,
+ PERF_MRRS_MASK = 0x7,
+ PERF_INTERVAL_SHIFT = 0x8,
+ PERF_INTERVAL_MASK = 0x7,
+ PERF_BURST_SIZE_SHIFT = 0xc,
+ PERF_BURST_SIZE_MASK = 0x7,
+ PERF_ARB_WEIGHT_SHIFT = 0x18,
+ PERF_ARB_WEIGHT_MASK = 0xff,
+};
+
+enum {
+ PERF_MIN_INTERVAL = 0,
+ PERF_MAX_INTERVAL = 0x7,
+ PERF_MIN_BURST_SIZE = 0,
+ PERF_MAX_BURST_SIZE = 0x7,
+ PERF_MIN_BURST_SCALE = 0,
+ PERF_MAX_BURST_SCALE = 0x2,
+ PERF_MIN_MRRS = 0,
+ PERF_MAX_MRRS = 0x7,
+};
+
+enum {
+ SE_BUF_BASE_SHIFT = 0x2,
+ SE_BUF_BASE_MASK = 0x1ff,
+ SE_BUF_LEN_SHIFT = 0xc,
+ SE_BUF_LEN_MASK = 0x1ff,
+ SE_THRESH_SHIFT = 0x17,
+ SE_THRESH_MASK = 0x1ff,
+};
+
+#define SWITCHTEC_CHAN_ENABLE BIT(1)
+
+struct chan_fw_regs {
+ u32 valid_en_se;
+ u32 cq_base_lo;
+ u32 cq_base_hi;
+ u16 cq_size;
+ u16 rsvd1;
+ u32 sq_base_lo;
+ u32 sq_base_hi;
+ u16 sq_size;
+ u16 rsvd2;
+ u32 int_vec;
+ u32 perf_cfg;
+ u32 rsvd3;
+ u32 perf_latency_selector;
+ u32 perf_fetched_se_cnt_lo;
+ u32 perf_fetched_se_cnt_hi;
+ u32 perf_byte_cnt_lo;
+ u32 perf_byte_cnt_hi;
+ u32 rsvd4;
+ u16 perf_se_pending;
+ u16 perf_se_buf_empty;
+ u32 perf_chan_idle;
+ u32 perf_lat_max;
+ u32 perf_lat_min;
+ u32 perf_lat_last;
+ u16 sq_current;
+ u16 sq_phase;
+ u16 cq_current;
+ u16 cq_phase;
+};
+
+enum cmd {
+ CMD_GET_HOST_LIST = 1,
+ CMD_REGISTER_BUF = 2,
+ CMD_UNREGISTER_BUF = 3,
+ CMD_GET_BUF_LIST = 4,
+ CMD_GET_OWN_BUF_LIST = 5,
+};
+
+enum cmd_status {
+ CMD_STATUS_IDLE = 0,
+ CMD_STATUS_INPROGRESS = 0x1,
+ CMD_STATUS_DONE = 0x2,
+ CMD_STATUS_ERROR = 0xFF,
+};
+
+struct switchtec_dma_chan {
+ struct switchtec_dma_dev *swdma_dev;
+ struct dma_chan dma_chan;
+ struct chan_hw_regs __iomem *mmio_chan_hw;
+ struct chan_fw_regs __iomem *mmio_chan_fw;
+
+ /* Serialize hardware control register access */
+ spinlock_t hw_ctrl_lock;
+
+ struct tasklet_struct desc_task;
+
+ /* Serialize descriptor preparation */
+ spinlock_t submit_lock;
+ bool ring_active;
+ int cid;
+
+ /* Serialize completion processing */
+ spinlock_t complete_lock;
+ bool comp_ring_active;
+
+ /* channel index and irq */
+ int index;
+ int irq;
+
+ /*
+ * In driver context, head is advanced by producer while
+ * tail is advanced by consumer.
+ */
+
+ /* the head and tail for both desc_ring and hw_sq */
+ int head;
+ int tail;
+ int phase_tag;
+ struct switchtec_dma_desc **desc_ring;
+ struct switchtec_dma_hw_se_desc *hw_sq;
+ dma_addr_t dma_addr_sq;
+
+ /* the tail for hw_cq */
+ int cq_tail;
+ struct switchtec_dma_hw_ce *hw_cq;
+ dma_addr_t dma_addr_cq;
+
+ struct list_head list;
+};
+
+struct switchtec_dma_dev {
+ struct dma_device dma_dev;
+ struct pci_dev __rcu *pdev;
+ struct switchtec_dma_chan **swdma_chans;
+ int chan_cnt;
+ int chan_status_irq;
+ void __iomem *bar;
+ struct tasklet_struct chan_status_task;
+};
+
+static struct switchtec_dma_chan *to_switchtec_dma_chan(struct dma_chan *c)
+{
+ return container_of(c, struct switchtec_dma_chan, dma_chan);
+}
+
+static struct device *to_chan_dev(struct switchtec_dma_chan *swdma_chan)
+{
+ return &swdma_chan->dma_chan.dev->device;
+}
+
+enum switchtec_dma_opcode {
+ SWITCHTEC_DMA_OPC_MEMCPY = 0,
+ SWITCHTEC_DMA_OPC_RDIMM = 0x1,
+ SWITCHTEC_DMA_OPC_WRIMM = 0x2,
+ SWITCHTEC_DMA_OPC_RHI = 0x6,
+ SWITCHTEC_DMA_OPC_NOP = 0x7,
+};
+
+struct switchtec_dma_hw_se_desc {
+ u8 opc;
+ u8 ctrl;
+ __le16 tlp_setting;
+ __le16 rsvd1;
+ __le16 cid;
+ __le32 byte_cnt;
+ __le32 addr_lo; /* SADDR_LO/WIADDR_LO */
+ __le32 addr_hi; /* SADDR_HI/WIADDR_HI */
+ __le32 daddr_lo;
+ __le32 daddr_hi;
+ __le16 dfid;
+ __le16 sfid;
+};
+
+#define SWITCHTEC_SE_DFM BIT(5)
+#define SWITCHTEC_SE_LIOF BIT(6)
+#define SWITCHTEC_SE_BRR BIT(7)
+#define SWITCHTEC_SE_CID_MASK GENMASK(15, 0)
+
+#define SWITCHTEC_CE_SC_LEN_ERR BIT(0)
+#define SWITCHTEC_CE_SC_UR BIT(1)
+#define SWITCHTEC_CE_SC_CA BIT(2)
+#define SWITCHTEC_CE_SC_RSVD_CPL BIT(3)
+#define SWITCHTEC_CE_SC_ECRC_ERR BIT(4)
+#define SWITCHTEC_CE_SC_EP_SET BIT(5)
+#define SWITCHTEC_CE_SC_D_RD_CTO BIT(8)
+#define SWITCHTEC_CE_SC_D_RIMM_UR BIT(9)
+#define SWITCHTEC_CE_SC_D_RIMM_CA BIT(10)
+#define SWITCHTEC_CE_SC_D_RIMM_RSVD_CPL BIT(11)
+#define SWITCHTEC_CE_SC_D_ECRC BIT(12)
+#define SWITCHTEC_CE_SC_D_EP_SET BIT(13)
+#define SWITCHTEC_CE_SC_D_BAD_CONNID BIT(14)
+#define SWITCHTEC_CE_SC_D_BAD_RHI_ADDR BIT(15)
+#define SWITCHTEC_CE_SC_D_INVD_CMD BIT(16)
+#define SWITCHTEC_CE_SC_MASK GENMASK(16, 0)
+
+struct switchtec_dma_hw_ce {
+ __le32 rdimm_cpl_dw0;
+ __le32 rdimm_cpl_dw1;
+ __le32 rsvd1;
+ __le32 cpl_byte_cnt;
+ __le16 sq_head;
+ __le16 rsvd2;
+ __le32 rsvd3;
+ __le32 sts_code;
+ __le16 cid;
+ __le16 phase_tag;
+};
+
+struct switchtec_dma_desc {
+ struct dma_async_tx_descriptor txd;
+ struct switchtec_dma_hw_se_desc *hw;
+ u32 orig_size;
+ bool completed;
+};
+
+#define SWITCHTEC_INVALID_HFID 0xffff
+
+#define SWITCHTEC_DMA_SQ_SIZE SZ_32K
+#define SWITCHTEC_DMA_CQ_SIZE SZ_32K
+
+#define SWITCHTEC_DMA_RING_SIZE SWITCHTEC_DMA_SQ_SIZE
+
+static int
+wait_for_chan_status(struct chan_hw_regs __iomem *chan_hw, u32 mask, bool set)
+{
+ u32 status;
+ int ret;
+
+ ret = readl_poll_timeout_atomic(&chan_hw->status, status,
+ (set && (status & mask)) ||
+ (!set && !(status & mask)),
+ 10, 100 * USEC_PER_MSEC);
+ if (ret)
+ return -EIO;
+
+ return 0;
+}
+
+static int halt_channel(struct switchtec_dma_chan *swdma_chan)
+{
+ struct chan_hw_regs __iomem *chan_hw = swdma_chan->mmio_chan_hw;
+ struct pci_dev *pdev;
+ int ret;
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+ if (!pdev) {
+ ret = -ENODEV;
+ goto unlock_and_exit;
+ }
+
+ spin_lock(&swdma_chan->hw_ctrl_lock);
+ writeb(SWITCHTEC_CHAN_CTRL_HALT, &chan_hw->ctrl);
+ ret = wait_for_chan_status(chan_hw, SWITCHTEC_CHAN_STS_HALTED, true);
+ spin_unlock(&swdma_chan->hw_ctrl_lock);
+
+unlock_and_exit:
+ rcu_read_unlock();
+ return ret;
+}
+
+static int unhalt_channel(struct switchtec_dma_chan *swdma_chan)
+{
+ u8 ctrl;
+ struct chan_hw_regs __iomem *chan_hw = swdma_chan->mmio_chan_hw;
+ struct pci_dev *pdev;
+ int ret;
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+ if (!pdev) {
+ ret = -ENODEV;
+ goto unlock_and_exit;
+ }
+
+ spin_lock(&swdma_chan->hw_ctrl_lock);
+ ctrl = readb(&chan_hw->ctrl);
+ ctrl &= ~SWITCHTEC_CHAN_CTRL_HALT;
+ writeb(ctrl, &chan_hw->ctrl);
+ ret = wait_for_chan_status(chan_hw, SWITCHTEC_CHAN_STS_HALTED, false);
+ spin_unlock(&swdma_chan->hw_ctrl_lock);
+
+unlock_and_exit:
+ rcu_read_unlock();
+ return ret;
+}
+
+static void flush_pci_write(struct chan_hw_regs __iomem *chan_hw)
+{
+ readl(&chan_hw->cq_head);
+}
+
+static int reset_channel(struct switchtec_dma_chan *swdma_chan)
+{
+ struct chan_hw_regs __iomem *chan_hw = swdma_chan->mmio_chan_hw;
+ struct pci_dev *pdev;
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+ if (!pdev) {
+ rcu_read_unlock();
+ return -ENODEV;
+ }
+
+ spin_lock(&swdma_chan->hw_ctrl_lock);
+ writel(SWITCHTEC_CHAN_CTRL_RESET | SWITCHTEC_CHAN_CTRL_ERR_PAUSE,
+ &chan_hw->ctrl);
+ flush_pci_write(chan_hw);
+
+ udelay(1000);
+
+ writel(SWITCHTEC_CHAN_CTRL_ERR_PAUSE, &chan_hw->ctrl);
+ spin_unlock(&swdma_chan->hw_ctrl_lock);
+ flush_pci_write(chan_hw);
+
+ rcu_read_unlock();
+ return 0;
+}
+
+static int pause_reset_channel(struct switchtec_dma_chan *swdma_chan)
+{
+ struct chan_hw_regs __iomem *chan_hw = swdma_chan->mmio_chan_hw;
+ struct pci_dev *pdev;
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+ if (!pdev) {
+ rcu_read_unlock();
+ return -ENODEV;
+ }
+
+ spin_lock(&swdma_chan->hw_ctrl_lock);
+ writeb(SWITCHTEC_CHAN_CTRL_PAUSE, &chan_hw->ctrl);
+ spin_unlock(&swdma_chan->hw_ctrl_lock);
+
+ flush_pci_write(chan_hw);
+
+ rcu_read_unlock();
+
+ /* wait 60ms to ensure no pending CEs */
+ mdelay(60);
+
+ return reset_channel(swdma_chan);
+}
+
+static int switchtec_dma_pause(struct dma_chan *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+ struct chan_hw_regs __iomem *chan_hw = swdma_chan->mmio_chan_hw;
+ struct pci_dev *pdev;
+ int ret;
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+ if (!pdev) {
+ ret = -ENODEV;
+ goto unlock_and_exit;
+ }
+
+ spin_lock(&swdma_chan->hw_ctrl_lock);
+ writeb(SWITCHTEC_CHAN_CTRL_PAUSE, &chan_hw->ctrl);
+ ret = wait_for_chan_status(chan_hw, SWITCHTEC_CHAN_STS_PAUSED, true);
+ spin_unlock(&swdma_chan->hw_ctrl_lock);
+
+unlock_and_exit:
+ rcu_read_unlock();
+ return ret;
+}
+
+static int switchtec_dma_resume(struct dma_chan *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+ struct chan_hw_regs __iomem *chan_hw = swdma_chan->mmio_chan_hw;
+ struct pci_dev *pdev;
+ int ret;
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+ if (!pdev) {
+ ret = -ENODEV;
+ goto unlock_and_exit;
+ }
+
+ spin_lock(&swdma_chan->hw_ctrl_lock);
+ writeb(0, &chan_hw->ctrl);
+ ret = wait_for_chan_status(chan_hw, SWITCHTEC_CHAN_STS_PAUSED, false);
+ spin_unlock(&swdma_chan->hw_ctrl_lock);
+
+unlock_and_exit:
+ rcu_read_unlock();
+ return ret;
+}
+
+enum chan_op {
+ ENABLE_CHAN,
+ DISABLE_CHAN,
+};
+
+static int channel_op(struct switchtec_dma_chan *swdma_chan, int op)
+{
+ struct chan_fw_regs __iomem *chan_fw = swdma_chan->mmio_chan_fw;
+ struct pci_dev *pdev;
+ u32 valid_en_se;
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+ if (!pdev) {
+ rcu_read_unlock();
+ return -ENODEV;
+ }
+
+ valid_en_se = readl(&chan_fw->valid_en_se);
+ if (op == ENABLE_CHAN)
+ valid_en_se |= SWITCHTEC_CHAN_ENABLE;
+ else
+ valid_en_se &= ~SWITCHTEC_CHAN_ENABLE;
+
+ writel(valid_en_se, &chan_fw->valid_en_se);
+
+ rcu_read_unlock();
+ return 0;
+}
+
+static int enable_channel(struct switchtec_dma_chan *swdma_chan)
+{
+ return channel_op(swdma_chan, ENABLE_CHAN);
+}
+
+static int disable_channel(struct switchtec_dma_chan *swdma_chan)
+{
+ return channel_op(swdma_chan, DISABLE_CHAN);
+}
+
+static struct switchtec_dma_desc *
+switchtec_dma_get_desc(struct switchtec_dma_chan *swdma_chan, int i)
+{
+ return swdma_chan->desc_ring[i];
+}
+
+static struct switchtec_dma_hw_ce *
+switchtec_dma_get_ce(struct switchtec_dma_chan *swdma_chan, int i)
+{
+ return &swdma_chan->hw_cq[i];
+}
+
+static void switchtec_dma_process_desc(struct switchtec_dma_chan *swdma_chan)
+{
+ struct device *chan_dev = to_chan_dev(swdma_chan);
+ struct dmaengine_result res;
+ struct switchtec_dma_desc *desc;
+ struct switchtec_dma_hw_ce *ce;
+ __le16 phase_tag;
+ int tail;
+ int cid;
+ int se_idx;
+ u32 sts_code;
+ int i;
+ __le32 *p;
+
+ do {
+ spin_lock_bh(&swdma_chan->complete_lock);
+ if (!swdma_chan->comp_ring_active) {
+ spin_unlock_bh(&swdma_chan->complete_lock);
+ break;
+ }
+
+ ce = switchtec_dma_get_ce(swdma_chan, swdma_chan->cq_tail);
+
+ /*
+ * phase_tag is updated by hardware, ensure the value is
+ * not from the cache
+ */
+ phase_tag = smp_load_acquire(&ce->phase_tag);
+ if (le16_to_cpu(phase_tag) == swdma_chan->phase_tag) {
+ spin_unlock_bh(&swdma_chan->complete_lock);
+ break;
+ }
+
+ cid = le16_to_cpu(ce->cid);
+ se_idx = cid & (SWITCHTEC_DMA_SQ_SIZE - 1);
+ desc = switchtec_dma_get_desc(swdma_chan, se_idx);
+
+ tail = swdma_chan->tail;
+
+ res.residue = desc->orig_size - le32_to_cpu(ce->cpl_byte_cnt);
+
+ sts_code = le32_to_cpu(ce->sts_code);
+
+ if (!(sts_code & SWITCHTEC_CE_SC_MASK)) {
+ res.result = DMA_TRANS_NOERROR;
+ } else {
+ if (sts_code & SWITCHTEC_CE_SC_D_RD_CTO)
+ res.result = DMA_TRANS_READ_FAILED;
+ else
+ res.result = DMA_TRANS_WRITE_FAILED;
+
+ dev_err(chan_dev, "CID 0x%04x failed, SC 0x%08x\n", cid,
+ (u32)(sts_code & SWITCHTEC_CE_SC_MASK));
+
+ p = (__le32 *)ce;
+ for (i = 0; i < sizeof(*ce) / 4; i++) {
+ dev_err(chan_dev, "CE DW%d: 0x%08x\n", i,
+ le32_to_cpu(*p));
+ p++;
+ }
+ }
+
+ desc->completed = true;
+
+ swdma_chan->cq_tail++;
+ swdma_chan->cq_tail &= SWITCHTEC_DMA_CQ_SIZE - 1;
+
+ rcu_read_lock();
+ if (!rcu_dereference(swdma_chan->swdma_dev->pdev)) {
+ rcu_read_unlock();
+ spin_unlock_bh(&swdma_chan->complete_lock);
+ return;
+ }
+ writew(swdma_chan->cq_tail, &swdma_chan->mmio_chan_hw->cq_head);
+ rcu_read_unlock();
+
+ if (swdma_chan->cq_tail == 0)
+ swdma_chan->phase_tag = !swdma_chan->phase_tag;
+
+ /* Out of order CE */
+ if (se_idx != tail) {
+ spin_unlock_bh(&swdma_chan->complete_lock);
+ continue;
+ }
+
+ do {
+ dma_cookie_complete(&desc->txd);
+ dma_descriptor_unmap(&desc->txd);
+ dmaengine_desc_get_callback_invoke(&desc->txd, &res);
+ desc->txd.callback = NULL;
+ desc->txd.callback_result = NULL;
+ desc->completed = false;
+
+ tail++;
+ tail &= SWITCHTEC_DMA_SQ_SIZE - 1;
+
+ /*
+ * Ensure the desc updates are visible before updating
+ * the tail index
+ */
+ smp_store_release(&swdma_chan->tail, tail);
+ desc = switchtec_dma_get_desc(swdma_chan,
+ swdma_chan->tail);
+ if (!desc->completed)
+ break;
+ } while (CIRC_CNT(READ_ONCE(swdma_chan->head), swdma_chan->tail,
+ SWITCHTEC_DMA_SQ_SIZE));
+
+ spin_unlock_bh(&swdma_chan->complete_lock);
+ } while (1);
+}
+
+static void
+switchtec_dma_abort_desc(struct switchtec_dma_chan *swdma_chan, int force)
+{
+ struct dmaengine_result res;
+ struct switchtec_dma_desc *desc;
+
+ if (!force)
+ switchtec_dma_process_desc(swdma_chan);
+
+ spin_lock_bh(&swdma_chan->complete_lock);
+
+ while (CIRC_CNT(swdma_chan->head, swdma_chan->tail,
+ SWITCHTEC_DMA_SQ_SIZE) >= 1) {
+ desc = switchtec_dma_get_desc(swdma_chan, swdma_chan->tail);
+
+ res.residue = desc->orig_size;
+ res.result = DMA_TRANS_ABORTED;
+
+ dma_cookie_complete(&desc->txd);
+ dma_descriptor_unmap(&desc->txd);
+ if (!force)
+ dmaengine_desc_get_callback_invoke(&desc->txd, &res);
+ desc->txd.callback = NULL;
+ desc->txd.callback_result = NULL;
+
+ swdma_chan->tail++;
+ swdma_chan->tail &= SWITCHTEC_DMA_SQ_SIZE - 1;
+ }
+
+ spin_unlock_bh(&swdma_chan->complete_lock);
+}
+
+static void switchtec_dma_chan_stop(struct switchtec_dma_chan *swdma_chan)
+{
+ int rc;
+
+ rc = halt_channel(swdma_chan);
+ if (rc)
+ return;
+
+ rcu_read_lock();
+ if (!rcu_dereference(swdma_chan->swdma_dev->pdev)) {
+ rcu_read_unlock();
+ return;
+ }
+
+ writel(0, &swdma_chan->mmio_chan_fw->sq_base_lo);
+ writel(0, &swdma_chan->mmio_chan_fw->sq_base_hi);
+ writel(0, &swdma_chan->mmio_chan_fw->cq_base_lo);
+ writel(0, &swdma_chan->mmio_chan_fw->cq_base_hi);
+
+ rcu_read_unlock();
+}
+
+static int switchtec_dma_terminate_all(struct dma_chan *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+
+ spin_lock_bh(&swdma_chan->complete_lock);
+ swdma_chan->comp_ring_active = false;
+ spin_unlock_bh(&swdma_chan->complete_lock);
+
+ return pause_reset_channel(swdma_chan);
+}
+
+static void switchtec_dma_synchronize(struct dma_chan *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+ int rc;
+
+ switchtec_dma_abort_desc(swdma_chan, 1);
+
+ rc = enable_channel(swdma_chan);
+ if (rc)
+ return;
+
+ rc = reset_channel(swdma_chan);
+ if (rc)
+ return;
+
+ rc = unhalt_channel(swdma_chan);
+ if (rc)
+ return;
+
+ spin_lock_bh(&swdma_chan->submit_lock);
+ swdma_chan->head = 0;
+ spin_unlock_bh(&swdma_chan->submit_lock);
+
+ spin_lock_bh(&swdma_chan->complete_lock);
+ swdma_chan->comp_ring_active = true;
+ swdma_chan->phase_tag = 0;
+ swdma_chan->tail = 0;
+ swdma_chan->cq_tail = 0;
+ swdma_chan->cid = 0;
+ dma_cookie_init(chan);
+ spin_unlock_bh(&swdma_chan->complete_lock);
+}
+
+static void switchtec_dma_desc_task(unsigned long data)
+{
+ struct switchtec_dma_chan *swdma_chan = (void *)data;
+
+ switchtec_dma_process_desc(swdma_chan);
+}
+
+static void switchtec_dma_chan_status_task(unsigned long data)
+{
+ struct switchtec_dma_dev *swdma_dev = (void *)data;
+ struct dma_device *dma_dev = &swdma_dev->dma_dev;
+ struct switchtec_dma_chan *swdma_chan;
+ struct chan_hw_regs __iomem *chan_hw;
+ struct dma_chan *chan;
+ struct device *chan_dev;
+ u32 chan_status;
+ int bit;
+
+ list_for_each_entry(chan, &dma_dev->channels, device_node) {
+ swdma_chan = to_switchtec_dma_chan(chan);
+ chan_dev = to_chan_dev(swdma_chan);
+ chan_hw = swdma_chan->mmio_chan_hw;
+
+ rcu_read_lock();
+ if (!rcu_dereference(swdma_dev->pdev)) {
+ rcu_read_unlock();
+ return;
+ }
+
+ chan_status = readl(&chan_hw->status);
+ chan_status &= SWITCHTEC_CHAN_STS_PAUSED_MASK;
+ rcu_read_unlock();
+
+ bit = ffs(chan_status);
+ if (!bit)
+ dev_dbg(chan_dev, "No pause bit set.");
+ else
+ dev_err(chan_dev, "Paused, %s\n",
+ channel_status_str[bit - 1]);
+ }
+}
+
+static struct dma_async_tx_descriptor *
+switchtec_dma_prep_desc(struct dma_chan *c, u16 dst_fid, dma_addr_t dma_dst,
+ u16 src_fid, dma_addr_t dma_src, u64 data,
+ size_t len, unsigned long flags)
+ __acquires(swdma_chan->submit_lock)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(c);
+ struct switchtec_dma_desc *desc;
+ int head;
+ int tail;
+
+ spin_lock_bh(&swdma_chan->submit_lock);
+
+ if (!swdma_chan->ring_active)
+ goto err_unlock;
+
+ tail = READ_ONCE(swdma_chan->tail);
+ head = swdma_chan->head;
+
+ if (!CIRC_SPACE(head, tail, SWITCHTEC_DMA_RING_SIZE))
+ goto err_unlock;
+
+ desc = switchtec_dma_get_desc(swdma_chan, head);
+
+ if (src_fid != SWITCHTEC_INVALID_HFID &&
+ dst_fid != SWITCHTEC_INVALID_HFID)
+ desc->hw->ctrl |= SWITCHTEC_SE_DFM;
+
+ if (flags & DMA_PREP_INTERRUPT)
+ desc->hw->ctrl |= SWITCHTEC_SE_LIOF;
+
+ if (flags & DMA_PREP_FENCE)
+ desc->hw->ctrl |= SWITCHTEC_SE_BRR;
+
+ desc->txd.flags = flags;
+
+ desc->completed = false;
+ desc->hw->opc = SWITCHTEC_DMA_OPC_MEMCPY;
+ desc->hw->addr_lo = cpu_to_le32(lower_32_bits(dma_src));
+ desc->hw->addr_hi = cpu_to_le32(upper_32_bits(dma_src));
+ desc->hw->daddr_lo = cpu_to_le32(lower_32_bits(dma_dst));
+ desc->hw->daddr_hi = cpu_to_le32(upper_32_bits(dma_dst));
+ desc->hw->byte_cnt = cpu_to_le32(len);
+ desc->hw->tlp_setting = 0;
+ desc->hw->dfid = cpu_to_le16(dst_fid);
+ desc->hw->sfid = cpu_to_le16(src_fid);
+ swdma_chan->cid &= SWITCHTEC_SE_CID_MASK;
+ desc->hw->cid = cpu_to_le16(swdma_chan->cid++);
+ desc->orig_size = len;
+
+ head++;
+ head &= SWITCHTEC_DMA_RING_SIZE - 1;
+
+ /*
+ * Ensure the desc updates are visible before updating the head index
+ */
+ smp_store_release(&swdma_chan->head, head);
+
+ /* return with the lock held, it will be released in tx_submit */
+
+ return &desc->txd;
+
+err_unlock:
+ /*
+ * Keep sparse happy by restoring an even lock count on
+ * this lock.
+ */
+ __acquire(swdma_chan->submit_lock);
+
+ spin_unlock_bh(&swdma_chan->submit_lock);
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+switchtec_dma_prep_memcpy(struct dma_chan *c, dma_addr_t dma_dst,
+ dma_addr_t dma_src, size_t len, unsigned long flags)
+ __acquires(swdma_chan->submit_lock)
+{
+ if (len > SWITCHTEC_DESC_MAX_SIZE) {
+ /*
+ * Keep sparse happy by restoring an even lock count on
+ * this lock.
+ */
+ __acquire(swdma_chan->submit_lock);
+ return NULL;
+ }
+
+ return switchtec_dma_prep_desc(c, SWITCHTEC_INVALID_HFID, dma_dst,
+ SWITCHTEC_INVALID_HFID, dma_src, 0, len,
+ flags);
+}
+
+static dma_cookie_t
+switchtec_dma_tx_submit(struct dma_async_tx_descriptor *desc)
+ __releases(swdma_chan->submit_lock)
+{
+ struct switchtec_dma_chan *swdma_chan =
+ to_switchtec_dma_chan(desc->chan);
+ dma_cookie_t cookie;
+
+ cookie = dma_cookie_assign(desc);
+
+ spin_unlock_bh(&swdma_chan->submit_lock);
+
+ return cookie;
+}
+
+static enum dma_status switchtec_dma_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+ enum dma_status ret;
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ if (ret == DMA_COMPLETE)
+ return ret;
+
+ switchtec_dma_process_desc(swdma_chan);
+
+ return dma_cookie_status(chan, cookie, txstate);
+}
+
+static void switchtec_dma_issue_pending(struct dma_chan *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+ struct switchtec_dma_dev *swdma_dev = swdma_chan->swdma_dev;
+
+ /*
+ * Ensure the desc updates are visible before starting the
+ * DMA engine.
+ */
+ wmb();
+
+ /*
+ * The sq_tail register is actually for the head of the
+ * submisssion queue. Chip has the opposite define of head/tail
+ * to the Linux kernel.
+ */
+
+ rcu_read_lock();
+ if (!rcu_dereference(swdma_dev->pdev)) {
+ rcu_read_unlock();
+ return;
+ }
+
+ spin_lock_bh(&swdma_chan->submit_lock);
+ writew(swdma_chan->head, &swdma_chan->mmio_chan_hw->sq_tail);
+ spin_unlock_bh(&swdma_chan->submit_lock);
+
+ rcu_read_unlock();
+}
+
+static irqreturn_t switchtec_dma_isr(int irq, void *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = chan;
+
+ if (swdma_chan->comp_ring_active)
+ tasklet_schedule(&swdma_chan->desc_task);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t switchtec_dma_chan_status_isr(int irq, void *dma)
+{
+ struct switchtec_dma_dev *swdma_dev = dma;
+
+ tasklet_schedule(&swdma_dev->chan_status_task);
+
+ return IRQ_HANDLED;
+}
+
+static void switchtec_dma_free_desc(struct switchtec_dma_chan *swdma_chan)
+{
+ struct switchtec_dma_dev *swdma_dev = swdma_chan->swdma_dev;
+ size_t size;
+ int i;
+
+ size = SWITCHTEC_DMA_SQ_SIZE * sizeof(*swdma_chan->hw_sq);
+ if (swdma_chan->hw_sq)
+ dma_free_coherent(swdma_dev->dma_dev.dev, size,
+ swdma_chan->hw_sq, swdma_chan->dma_addr_sq);
+
+ size = SWITCHTEC_DMA_CQ_SIZE * sizeof(*swdma_chan->hw_cq);
+ if (swdma_chan->hw_cq)
+ dma_free_coherent(swdma_dev->dma_dev.dev, size,
+ swdma_chan->hw_cq, swdma_chan->dma_addr_cq);
+
+ if (swdma_chan->desc_ring) {
+ for (i = 0; i < SWITCHTEC_DMA_RING_SIZE; i++)
+ kfree(swdma_chan->desc_ring[i]);
+
+ kfree(swdma_chan->desc_ring);
+ }
+}
+
+static int switchtec_dma_alloc_desc(struct switchtec_dma_chan *swdma_chan)
+{
+ struct switchtec_dma_dev *swdma_dev = swdma_chan->swdma_dev;
+ struct chan_fw_regs __iomem *chan_fw = swdma_chan->mmio_chan_fw;
+ struct pci_dev *pdev;
+ struct switchtec_dma_desc *desc;
+ size_t size;
+ int rc;
+ int i;
+
+ swdma_chan->head = 0;
+ swdma_chan->tail = 0;
+ swdma_chan->cq_tail = 0;
+
+ size = SWITCHTEC_DMA_SQ_SIZE * sizeof(*swdma_chan->hw_sq);
+ swdma_chan->hw_sq = dma_alloc_coherent(swdma_dev->dma_dev.dev, size,
+ &swdma_chan->dma_addr_sq,
+ GFP_NOWAIT);
+ if (!swdma_chan->hw_sq) {
+ rc = -ENOMEM;
+ goto free_and_exit;
+ }
+
+ size = SWITCHTEC_DMA_CQ_SIZE * sizeof(*swdma_chan->hw_cq);
+ swdma_chan->hw_cq = dma_alloc_coherent(swdma_dev->dma_dev.dev, size,
+ &swdma_chan->dma_addr_cq,
+ GFP_NOWAIT);
+ if (!swdma_chan->hw_cq) {
+ rc = -ENOMEM;
+ goto free_and_exit;
+ }
+
+ /* reset host phase tag */
+ swdma_chan->phase_tag = 0;
+
+ size = sizeof(*swdma_chan->desc_ring);
+ swdma_chan->desc_ring = kcalloc(SWITCHTEC_DMA_RING_SIZE, size,
+ GFP_NOWAIT);
+ if (!swdma_chan->desc_ring) {
+ rc = -ENOMEM;
+ goto free_and_exit;
+ }
+
+ for (i = 0; i < SWITCHTEC_DMA_RING_SIZE; i++) {
+ desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
+ if (!desc) {
+ rc = -ENOMEM;
+ goto free_and_exit;
+ }
+
+ dma_async_tx_descriptor_init(&desc->txd, &swdma_chan->dma_chan);
+ desc->txd.tx_submit = switchtec_dma_tx_submit;
+ desc->hw = &swdma_chan->hw_sq[i];
+ desc->completed = true;
+
+ swdma_chan->desc_ring[i] = desc;
+ }
+
+ rcu_read_lock();
+ pdev = rcu_dereference(swdma_dev->pdev);
+ if (!pdev) {
+ rcu_read_unlock();
+ rc = -ENODEV;
+ goto free_and_exit;
+ }
+
+ /* set sq/cq */
+ writel(lower_32_bits(swdma_chan->dma_addr_sq), &chan_fw->sq_base_lo);
+ writel(upper_32_bits(swdma_chan->dma_addr_sq), &chan_fw->sq_base_hi);
+ writel(lower_32_bits(swdma_chan->dma_addr_cq), &chan_fw->cq_base_lo);
+ writel(upper_32_bits(swdma_chan->dma_addr_cq), &chan_fw->cq_base_hi);
+
+ writew(SWITCHTEC_DMA_SQ_SIZE, &swdma_chan->mmio_chan_fw->sq_size);
+ writew(SWITCHTEC_DMA_CQ_SIZE, &swdma_chan->mmio_chan_fw->cq_size);
+
+ rcu_read_unlock();
+ return 0;
+
+free_and_exit:
+ switchtec_dma_free_desc(swdma_chan);
+ return rc;
+}
+
+static int switchtec_dma_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+ struct switchtec_dma_dev *swdma_dev = swdma_chan->swdma_dev;
+ u32 perf_cfg;
+ int rc;
+
+ rc = switchtec_dma_alloc_desc(swdma_chan);
+ if (rc)
+ return rc;
+
+ rc = enable_channel(swdma_chan);
+ if (rc)
+ return rc;
+
+ rc = reset_channel(swdma_chan);
+ if (rc)
+ return rc;
+
+ rc = unhalt_channel(swdma_chan);
+ if (rc)
+ return rc;
+
+ swdma_chan->ring_active = true;
+ swdma_chan->comp_ring_active = true;
+ swdma_chan->cid = 0;
+
+ dma_cookie_init(chan);
+
+ rcu_read_lock();
+ if (!rcu_dereference(swdma_dev->pdev)) {
+ rcu_read_unlock();
+ return -ENODEV;
+ }
+
+ perf_cfg = readl(&swdma_chan->mmio_chan_fw->perf_cfg);
+ rcu_read_unlock();
+
+ dev_dbg(&chan->dev->device, "Burst Size: 0x%x",
+ (perf_cfg >> PERF_BURST_SIZE_SHIFT) & PERF_BURST_SIZE_MASK);
+
+ dev_dbg(&chan->dev->device, "Burst Scale: 0x%x",
+ (perf_cfg >> PERF_BURST_SCALE_SHIFT) & PERF_BURST_SCALE_MASK);
+
+ dev_dbg(&chan->dev->device, "Interval: 0x%x",
+ (perf_cfg >> PERF_INTERVAL_SHIFT) & PERF_INTERVAL_MASK);
+
+ dev_dbg(&chan->dev->device, "Arb Weight: 0x%x",
+ (perf_cfg >> PERF_ARB_WEIGHT_SHIFT) & PERF_ARB_WEIGHT_MASK);
+
+ dev_dbg(&chan->dev->device, "MRRS: 0x%x",
+ (perf_cfg >> PERF_MRRS_SHIFT) & PERF_MRRS_MASK);
+
+ return SWITCHTEC_DMA_SQ_SIZE;
+}
+
+static void switchtec_dma_free_chan_resources(struct dma_chan *chan)
+{
+ struct switchtec_dma_chan *swdma_chan = to_switchtec_dma_chan(chan);
+
+ spin_lock_bh(&swdma_chan->submit_lock);
+ swdma_chan->ring_active = false;
+ spin_unlock_bh(&swdma_chan->submit_lock);
+
+ spin_lock_bh(&swdma_chan->complete_lock);
+ swdma_chan->comp_ring_active = false;
+ spin_unlock_bh(&swdma_chan->complete_lock);
+
+ switchtec_dma_chan_stop(swdma_chan);
+
+ tasklet_kill(&swdma_chan->desc_task);
+
+ switchtec_dma_abort_desc(swdma_chan, 0);
+
+ switchtec_dma_free_desc(swdma_chan);
+
+ disable_channel(swdma_chan);
+}
+
+static int switchtec_dma_chan_init(struct switchtec_dma_dev *swdma_dev, int i)
+{
+ struct dma_device *dma = &swdma_dev->dma_dev;
+ struct pci_dev *pdev = rcu_dereference(swdma_dev->pdev);
+ struct switchtec_dma_chan *swdma_chan;
+ struct dma_chan *chan;
+ u32 perf_cfg;
+ u32 valid_en_se;
+ u32 thresh;
+ int se_buf_len;
+ int irq;
+ int rc;
+
+ swdma_chan = kzalloc(sizeof(*swdma_chan), GFP_KERNEL);
+ if (!swdma_chan)
+ return -ENOMEM;
+
+ swdma_chan->phase_tag = 0;
+ swdma_chan->index = i;
+ swdma_chan->swdma_dev = swdma_dev;
+
+ swdma_chan->mmio_chan_fw =
+ swdma_dev->bar + SWITCHTEC_DMAC_CHAN_CFG_STS_OFFSET +
+ i * SWITCHTEC_DMA_CHAN_FW_REGS_SIZE;
+ swdma_chan->mmio_chan_hw =
+ swdma_dev->bar + SWITCHTEC_DMAC_CHAN_CTRL_OFFSET +
+ i * SWITCHTEC_DMA_CHAN_HW_REGS_SIZE;
+
+ swdma_dev->swdma_chans[i] = swdma_chan;
+
+ rc = pause_reset_channel(swdma_chan);
+ if (rc)
+ goto free_and_exit;
+
+ perf_cfg = readl(&swdma_chan->mmio_chan_fw->perf_cfg);
+
+ /* init perf tuner */
+ perf_cfg = PERF_BURST_SCALE << PERF_BURST_SCALE_SHIFT;
+ perf_cfg |= PERF_MRRS << PERF_MRRS_SHIFT;
+ perf_cfg |= PERF_INTERVAL << PERF_INTERVAL_SHIFT;
+ perf_cfg |= PERF_BURST_SIZE << PERF_BURST_SIZE_SHIFT;
+ perf_cfg |= PERF_ARB_WEIGHT << PERF_ARB_WEIGHT_SHIFT;
+
+ writel(perf_cfg, &swdma_chan->mmio_chan_fw->perf_cfg);
+
+ valid_en_se = readl(&swdma_chan->mmio_chan_fw->valid_en_se);
+
+ dev_dbg(&pdev->dev, "Channel %d: SE buffer base %d\n",
+ i, (valid_en_se >> SE_BUF_BASE_SHIFT) & SE_BUF_BASE_MASK);
+
+ se_buf_len = (valid_en_se >> SE_BUF_LEN_SHIFT) & SE_BUF_LEN_MASK;
+ dev_dbg(&pdev->dev, "Channel %d: SE buffer count %d\n", i, se_buf_len);
+
+ thresh = se_buf_len / 2;
+ valid_en_se |= (thresh & SE_THRESH_MASK) << SE_THRESH_SHIFT;
+ writel(valid_en_se, &swdma_chan->mmio_chan_fw->valid_en_se);
+
+ /* request irqs */
+ irq = readl(&swdma_chan->mmio_chan_fw->int_vec);
+ dev_dbg(&pdev->dev, "Channel %d: CE irq vector %d\n", i, irq);
+
+ rc = pci_request_irq(pdev, irq, switchtec_dma_isr, NULL, swdma_chan,
+ KBUILD_MODNAME);
+ if (rc)
+ goto free_and_exit;
+
+ swdma_chan->irq = irq;
+
+ spin_lock_init(&swdma_chan->hw_ctrl_lock);
+ spin_lock_init(&swdma_chan->submit_lock);
+ spin_lock_init(&swdma_chan->complete_lock);
+ tasklet_init(&swdma_chan->desc_task, switchtec_dma_desc_task,
+ (unsigned long)swdma_chan);
+
+ chan = &swdma_chan->dma_chan;
+ chan->device = dma;
+ dma_cookie_init(chan);
+
+ list_add_tail(&chan->device_node, &dma->channels);
+
+ return 0;
+
+free_and_exit:
+ kfree(swdma_chan);
+ return rc;
+}
+
+static int switchtec_dma_chan_free(struct switchtec_dma_chan *swdma_chan)
+{
+ struct pci_dev *pdev = rcu_dereference(swdma_chan->swdma_dev->pdev);
+
+ spin_lock_bh(&swdma_chan->submit_lock);
+ swdma_chan->ring_active = false;
+ spin_unlock_bh(&swdma_chan->submit_lock);
+
+ spin_lock_bh(&swdma_chan->complete_lock);
+ swdma_chan->comp_ring_active = false;
+ spin_unlock_bh(&swdma_chan->complete_lock);
+
+ pci_free_irq(pdev, swdma_chan->irq, swdma_chan);
+
+ switchtec_dma_chan_stop(swdma_chan);
+
+ return 0;
+}
+
+static int switchtec_dma_chans_release(struct switchtec_dma_dev *swdma_dev)
+{
+ int i;
+
+ for (i = 0; i < swdma_dev->chan_cnt; i++)
+ switchtec_dma_chan_free(swdma_dev->swdma_chans[i]);
+
+ return 0;
+}
+
+static int switchtec_dma_chans_enumerate(struct switchtec_dma_dev *swdma_dev,
+ int chan_cnt)
+{
+ struct dma_device *dma = &swdma_dev->dma_dev;
+ struct pci_dev *pdev = rcu_dereference(swdma_dev->pdev);
+ int base;
+ int cnt;
+ int rc;
+ int i;
+
+ swdma_dev->swdma_chans = kcalloc(chan_cnt,
+ sizeof(*swdma_dev->swdma_chans),
+ GFP_KERNEL);
+
+ if (!swdma_dev->swdma_chans)
+ return -ENOMEM;
+
+ base = readw(swdma_dev->bar + SWITCHTEC_REG_SE_BUF_BASE);
+ cnt = readw(swdma_dev->bar + SWITCHTEC_REG_SE_BUF_CNT);
+
+ dev_dbg(&pdev->dev, "EP SE buffer base %d\n", base);
+ dev_dbg(&pdev->dev, "EP SE buffer count %d\n", cnt);
+
+ INIT_LIST_HEAD(&dma->channels);
+
+ for (i = 0; i < chan_cnt; i++) {
+ rc = switchtec_dma_chan_init(swdma_dev, i);
+ if (rc) {
+ dev_err(&pdev->dev, "Channel %d: init channel failed\n",
+ i);
+ chan_cnt = i;
+ goto err_exit;
+ }
+ }
+
+ return chan_cnt;
+
+err_exit:
+ for (i = 0; i < chan_cnt; i++)
+ switchtec_dma_chan_free(swdma_dev->swdma_chans[i]);
+
+ kfree(swdma_dev->swdma_chans);
+
+ return rc;
+}
+
+static void switchtec_dma_release(struct dma_device *dma_dev)
+{
+ int i;
+ struct switchtec_dma_dev *swdma_dev =
+ container_of(dma_dev, struct switchtec_dma_dev, dma_dev);
+
+ for (i = 0; i < swdma_dev->chan_cnt; i++)
+ kfree(swdma_dev->swdma_chans[i]);
+
+ kfree(swdma_dev->swdma_chans);
+
+ put_device(dma_dev->dev);
+ kfree(swdma_dev);
+}
+
+static int switchtec_dma_create(struct pci_dev *pdev)
+{
+ struct switchtec_dma_dev *swdma_dev;
+ struct dma_device *dma;
+ struct dma_chan *chan;
+ int chan_cnt;
+ int nr_vecs;
+ int irq;
+ int rc;
+
+ /*
+ * Create the switchtec dma device
+ */
+ swdma_dev = kzalloc(sizeof(*swdma_dev), GFP_KERNEL);
+ if (!swdma_dev)
+ return -ENOMEM;
+
+ swdma_dev->bar = ioremap(pci_resource_start(pdev, 0),
+ pci_resource_len(pdev, 0));
+
+ pci_info(pdev, "Switchtec PSX/PFX DMA EP\n");
+
+ RCU_INIT_POINTER(swdma_dev->pdev, pdev);
+
+ nr_vecs = pci_msix_vec_count(pdev);
+ rc = pci_alloc_irq_vectors(pdev, nr_vecs, nr_vecs, PCI_IRQ_MSIX);
+ if (rc < 0)
+ goto err_exit;
+
+ tasklet_init(&swdma_dev->chan_status_task,
+ switchtec_dma_chan_status_task,
+ (unsigned long)swdma_dev);
+
+ irq = readw(swdma_dev->bar + SWITCHTEC_REG_CHAN_STS_VEC);
+ pci_dbg(pdev, "Channel pause irq vector %d\n", irq);
+
+ rc = pci_request_irq(pdev, irq, switchtec_dma_chan_status_isr, NULL,
+ swdma_dev, KBUILD_MODNAME);
+ if (rc)
+ goto err_exit;
+
+ swdma_dev->chan_status_irq = irq;
+
+ chan_cnt = readl(swdma_dev->bar + SWITCHTEC_REG_CHAN_CNT);
+ if (!chan_cnt) {
+ pci_err(pdev, "No channel configured.\n");
+ rc = -ENXIO;
+ goto err_exit;
+ }
+
+ chan_cnt = switchtec_dma_chans_enumerate(swdma_dev, chan_cnt);
+ if (chan_cnt < 0) {
+ pci_err(pdev, "Failed to enumerate dma channels: %d\n",
+ chan_cnt);
+ rc = -ENXIO;
+ goto err_exit;
+ }
+
+ swdma_dev->chan_cnt = chan_cnt;
+
+ dma = &swdma_dev->dma_dev;
+ dma->copy_align = DMAENGINE_ALIGN_1_BYTE;
+ dma_cap_set(DMA_MEMCPY, dma->cap_mask);
+ dma_cap_set(DMA_PRIVATE, dma->cap_mask);
+ dma->dev = get_device(&pdev->dev);
+
+ dma->device_alloc_chan_resources = switchtec_dma_alloc_chan_resources;
+ dma->device_free_chan_resources = switchtec_dma_free_chan_resources;
+ dma->device_prep_dma_memcpy = switchtec_dma_prep_memcpy;
+ dma->device_issue_pending = switchtec_dma_issue_pending;
+ dma->device_tx_status = switchtec_dma_tx_status;
+ dma->device_pause = switchtec_dma_pause;
+ dma->device_resume = switchtec_dma_resume;
+ dma->device_terminate_all = switchtec_dma_terminate_all;
+ dma->device_synchronize = switchtec_dma_synchronize;
+ dma->device_release = switchtec_dma_release;
+
+ rc = dma_async_device_register(dma);
+ if (rc) {
+ pci_err(pdev, "Failed to register dma device: %d\n", rc);
+ goto err_chans_release_exit;
+ }
+
+ pci_info(pdev, "Channel count: %d\n", chan_cnt);
+
+ list_for_each_entry(chan, &dma->channels, device_node)
+ pci_info(pdev, "%s\n", dma_chan_name(chan));
+
+ pci_set_drvdata(pdev, swdma_dev);
+
+ return 0;
+
+err_chans_release_exit:
+ switchtec_dma_chans_release(swdma_dev);
+
+err_exit:
+ if (swdma_dev->chan_status_irq)
+ free_irq(swdma_dev->chan_status_irq, swdma_dev);
+
+ iounmap(swdma_dev->bar);
+ kfree(swdma_dev);
+ return rc;
+}
+
+static int switchtec_dma_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ int rc;
+
+ rc = pci_enable_device(pdev);
+ if (rc)
+ return rc;
+
+ rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+ if (rc)
+ goto err_disable;
+
+ rc = pci_request_mem_regions(pdev, KBUILD_MODNAME);
+ if (rc)
+ goto err_disable;
+
+ pci_set_master(pdev);
+
+ rc = switchtec_dma_create(pdev);
+ if (rc)
+ goto err_free;
+
+ pci_info(pdev, "Switchtec DMA Channels Registered\n");
+
+ return 0;
+
+err_free:
+ pci_free_irq_vectors(pdev);
+ pci_release_mem_regions(pdev);
+
+err_disable:
+ pci_disable_device(pdev);
+
+ return rc;
+}
+
+static void switchtec_dma_remove(struct pci_dev *pdev)
+{
+ struct switchtec_dma_dev *swdma_dev = pci_get_drvdata(pdev);
+
+ switchtec_dma_chans_release(swdma_dev);
+
+ tasklet_kill(&swdma_dev->chan_status_task);
+
+ rcu_assign_pointer(swdma_dev->pdev, NULL);
+ synchronize_rcu();
+
+ pci_free_irq(pdev, swdma_dev->chan_status_irq, swdma_dev);
+
+ pci_free_irq_vectors(pdev);
+
+ dma_async_device_unregister(&swdma_dev->dma_dev);
+
+ iounmap(swdma_dev->bar);
+ pci_release_mem_regions(pdev);
+ pci_disable_device(pdev);
+
+ pci_info(pdev, "Switchtec DMA Channels Unregistered\n");
+}
+
+/*
+ * Also use the class code to identify the devices, as some of the
+ * device IDs are also used for other devices with other classes by
+ * Microsemi.
+ */
+#define SWITCHTEC_DMA_DEVICE(device_id) \
+ { \
+ .vendor = PCI_VENDOR_ID_MICROSEMI, \
+ .device = device_id, \
+ .subvendor = PCI_ANY_ID, \
+ .subdevice = PCI_ANY_ID, \
+ .class = PCI_CLASS_SYSTEM_OTHER << 8, \
+ .class_mask = 0xFFFFFFFF, \
+ }
+
+static const struct pci_device_id switchtec_dma_pci_tbl[] = {
+ SWITCHTEC_DMA_DEVICE(0x4000), /* PFX 100XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4084), /* PFX 84XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4068), /* PFX 68XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4052), /* PFX 52XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4036), /* PFX 36XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4028), /* PFX 28XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4100), /* PSX 100XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4184), /* PSX 84XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4168), /* PSX 68XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4152), /* PSX 52XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4136), /* PSX 36XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4128), /* PSX 28XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4352), /* PFXA 52XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4336), /* PFXA 36XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4328), /* PFXA 28XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4452), /* PSXA 52XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4436), /* PSXA 36XG4 */
+ SWITCHTEC_DMA_DEVICE(0x4428), /* PSXA 28XG4 */
+ {0}
+};
+MODULE_DEVICE_TABLE(pci, switchtec_dma_pci_tbl);
+
+static struct pci_driver switchtec_dma_pci_driver = {
+ .name = KBUILD_MODNAME,
+ .id_table = switchtec_dma_pci_tbl,
+ .probe = switchtec_dma_probe,
+ .remove = switchtec_dma_remove,
+};
+module_pci_driver(switchtec_dma_pci_driver);