Message-ID: <20200923194056.GY3411@earth.li>
Date:   Wed, 23 Sep 2020 20:40:56 +0100
From:   Jonathan McDowell <noodles@...th.li>
To:     Andy Gross <agross@...nel.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Dan Williams <dan.j.williams@...el.com>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        Thomas Pedersen <twp@...eaurora.org>,
        Vinod Koul <vkoul@...nel.org>, linux-kernel@...r.kernel.org,
        linux-arm-msm@...r.kernel.org, dmaengine@...r.kernel.org
Subject: [PATCH v4] dmaengine: qcom: Add ADM driver

Add the DMA engine driver for the QCOM Application Data Mover (ADM) DMA
controller found in the MSM8x60 and IPQ/APQ8064 platforms.

The ADM supports both memory to memory transactions and memory
to/from peripheral device transactions.  The controller also provides
flow control capabilities for transactions to/from peripheral devices.

The initial release of this driver supports slave transfers to/from
peripherals and also incorporates CRCI (client rate control interface)
flow control.

Signed-off-by: Andy Gross <agross@...eaurora.org>
Signed-off-by: Thomas Pedersen <twp@...eaurora.org>
Signed-off-by: Jonathan McDowell <noodles@...th.li>

(I'm not sure how best to attribute this. It's originally from Andy
Gross, the version I picked up was a later version from Thomas Pedersen,
and I can't find clear indication of why the latest version wasn't
applied. The device tree details were added back in September 2014. The
driver is the missing piece in mainline for IPQ8064 NAND support and
I've been using it successfully with my RB3011 device on 5.8+)

v4:
- Reorder probe function to acquire resources before enabling anything
v3:
- Depend on !PHYS_ADDR_T_64BIT rather than !64BIT as reported by kernel
  test robot <lkp@...el.com>
v2:
- Address Vinod's review comments
  - GFP_NOWAIT instead of GFP_ATOMIC
  - Use devm_platform_ioremap_resource()
  - Call tasklet_kill on remove
  - Sort Kconfig/Makefile entries
  - SPDX identifier
  - Formatting fixes for checkpatch --strict
---
 drivers/dma/qcom/Kconfig    |  11 +
 drivers/dma/qcom/Makefile   |   1 +
 drivers/dma/qcom/qcom_adm.c | 903 ++++++++++++++++++++++++++++++++++++
 3 files changed, 915 insertions(+)
 create mode 100644 drivers/dma/qcom/qcom_adm.c

diff --git a/drivers/dma/qcom/Kconfig b/drivers/dma/qcom/Kconfig
index 3bcb689162c6..0389d60d2604 100644
--- a/drivers/dma/qcom/Kconfig
+++ b/drivers/dma/qcom/Kconfig
@@ -1,4 +1,15 @@
 # SPDX-License-Identifier: GPL-2.0-only
+config QCOM_ADM
+	tristate "Qualcomm ADM support"
+	depends on (ARCH_QCOM || COMPILE_TEST) && !PHYS_ADDR_T_64BIT
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  Enable support for the Qualcomm Application Data Mover (ADM) DMA
+	  controller, as present on MSM8x60, APQ8064, and IPQ8064 devices.
+	  This controller provides DMA capabilities for both general purpose
+	  and on-chip peripheral devices.
+
 config QCOM_BAM_DMA
 	tristate "QCOM BAM DMA support"
 	depends on ARCH_QCOM || (COMPILE_TEST && OF && ARM)
diff --git a/drivers/dma/qcom/Makefile b/drivers/dma/qcom/Makefile
index 1ae92da88b0c..346e643fbb6d 100644
--- a/drivers/dma/qcom/Makefile
+++ b/drivers/dma/qcom/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_QCOM_ADM) += qcom_adm.o
 obj-$(CONFIG_QCOM_BAM_DMA) += bam_dma.o
 obj-$(CONFIG_QCOM_HIDMA_MGMT) += hdma_mgmt.o
 hdma_mgmt-objs	 := hidma_mgmt.o hidma_mgmt_sys.o
diff --git a/drivers/dma/qcom/qcom_adm.c b/drivers/dma/qcom/qcom_adm.c
new file mode 100644
index 000000000000..9b6f8e050ecc
--- /dev/null
+++ b/drivers/dma/qcom/qcom_adm.c
@@ -0,0 +1,903 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_dma.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+
+#include "../dmaengine.h"
+#include "../virt-dma.h"
+
+/* ADM registers - calculated from channel number and security domain */
+#define ADM_CHAN_MULTI			0x4
+#define ADM_CI_MULTI			0x4
+#define ADM_CRCI_MULTI			0x4
+#define ADM_EE_MULTI			0x800
+#define ADM_CHAN_OFFS(chan)		(ADM_CHAN_MULTI * (chan))
+#define ADM_EE_OFFS(ee)			(ADM_EE_MULTI * (ee))
+#define ADM_CHAN_EE_OFFS(chan, ee)	(ADM_CHAN_OFFS(chan) + ADM_EE_OFFS(ee))
+#define ADM_CHAN_OFFS(chan)		(ADM_CHAN_MULTI * (chan))
+#define ADM_CI_OFFS(ci)			(ADM_CHAN_OFF(ci))
+#define ADM_CH_CMD_PTR(chan, ee)	(ADM_CHAN_EE_OFFS(chan, ee))
+#define ADM_CH_RSLT(chan, ee)		(0x40 + ADM_CHAN_EE_OFFS(chan, ee))
+#define ADM_CH_FLUSH_STATE0(chan, ee)	(0x80 + ADM_CHAN_EE_OFFS(chan, ee))
+#define ADM_CH_STATUS_SD(chan, ee)	(0x200 + ADM_CHAN_EE_OFFS(chan, ee))
+#define ADM_CH_CONF(chan)		(0x240 + ADM_CHAN_OFFS(chan))
+#define ADM_CH_RSLT_CONF(chan, ee)	(0x300 + ADM_CHAN_EE_OFFS(chan, ee))
+#define ADM_SEC_DOMAIN_IRQ_STATUS(ee)	(0x380 + ADM_EE_OFFS(ee))
+#define ADM_CI_CONF(ci)			(0x390 + (ci) * ADM_CI_MULTI)
+#define ADM_GP_CTL			0x3d8
+#define ADM_CRCI_CTL(crci, ee)		(0x400 + (crci) * ADM_CRCI_MULTI + \
+						ADM_EE_OFFS(ee))
+
+/* channel status */
+#define ADM_CH_STATUS_VALID		BIT(1)
+
+/* channel result */
+#define ADM_CH_RSLT_VALID		BIT(31)
+#define ADM_CH_RSLT_ERR			BIT(3)
+#define ADM_CH_RSLT_FLUSH		BIT(2)
+#define ADM_CH_RSLT_TPD			BIT(1)
+
+/* channel conf */
+#define ADM_CH_CONF_SHADOW_EN		BIT(12)
+#define ADM_CH_CONF_MPU_DISABLE		BIT(11)
+#define ADM_CH_CONF_PERM_MPU_CONF	BIT(9)
+#define ADM_CH_CONF_FORCE_RSLT_EN	BIT(7)
+#define ADM_CH_CONF_SEC_DOMAIN(ee)	((((ee) & 0x3) << 4) | (((ee) & 0x4) << 11))
+
+/* channel result conf */
+#define ADM_CH_RSLT_CONF_FLUSH_EN	BIT(1)
+#define ADM_CH_RSLT_CONF_IRQ_EN		BIT(0)
+
+/* CRCI CTL */
+#define ADM_CRCI_CTL_MUX_SEL		BIT(18)
+#define ADM_CRCI_CTL_RST		BIT(17)
+
+/* CI configuration */
+#define ADM_CI_RANGE_END(x)		((x) << 24)
+#define ADM_CI_RANGE_START(x)		((x) << 16)
+#define ADM_CI_BURST_4_WORDS		BIT(2)
+#define ADM_CI_BURST_8_WORDS		BIT(3)
+
+/* GP CTL */
+#define ADM_GP_CTL_LP_EN		BIT(12)
+#define ADM_GP_CTL_LP_CNT(x)		((x) << 8)
+
+/* Command pointer list entry */
+#define ADM_CPLE_LP			BIT(31)
+#define ADM_CPLE_CMD_PTR_LIST		BIT(29)
+
+/* Command list entry */
+#define ADM_CMD_LC			BIT(31)
+#define ADM_CMD_DST_CRCI(n)		(((n) & 0xf) << 7)
+#define ADM_CMD_SRC_CRCI(n)		(((n) & 0xf) << 3)
+
+#define ADM_CMD_TYPE_SINGLE		0x0
+#define ADM_CMD_TYPE_BOX		0x3
+
+#define ADM_CRCI_MUX_SEL		BIT(4)
+#define ADM_DESC_ALIGN			8
+#define ADM_MAX_XFER			(SZ_64K - 1)
+#define ADM_MAX_ROWS			(SZ_64K - 1)
+#define ADM_MAX_CHANNELS		16
+
+struct adm_desc_hw_box {
+	u32 cmd;
+	u32 src_addr;
+	u32 dst_addr;
+	u32 row_len;
+	u32 num_rows;
+	u32 row_offset;
+};
+
+struct adm_desc_hw_single {
+	u32 cmd;
+	u32 src_addr;
+	u32 dst_addr;
+	u32 len;
+};
+
+struct adm_async_desc {
+	struct virt_dma_desc vd;
+	struct adm_device *adev;
+
+	size_t length;
+	enum dma_transfer_direction dir;
+	dma_addr_t dma_addr;
+	size_t dma_len;
+
+	void *cpl;
+	dma_addr_t cp_addr;
+	u32 crci;
+	u32 mux;
+	u32 blk_size;
+};
+
+struct adm_chan {
+	struct virt_dma_chan vc;
+	struct adm_device *adev;
+
+	/* parsed from DT */
+	u32 id;			/* channel id */
+
+	struct adm_async_desc *curr_txd;
+	struct dma_slave_config slave;
+	struct list_head node;
+
+	int error;
+	int initialized;
+};
+
+static inline struct adm_chan *to_adm_chan(struct dma_chan *common)
+{
+	return container_of(common, struct adm_chan, vc.chan);
+}
+
+struct adm_device {
+	void __iomem *regs;
+	struct device *dev;
+	struct dma_device common;
+	struct device_dma_parameters dma_parms;
+	struct adm_chan *channels;
+
+	u32 ee;
+
+	struct clk *core_clk;
+	struct clk *iface_clk;
+
+	struct reset_control *clk_reset;
+	struct reset_control *c0_reset;
+	struct reset_control *c1_reset;
+	struct reset_control *c2_reset;
+	int irq;
+};
+
+/**
+ * adm_free_chan - Frees dma resources associated with the specific channel
+ *
+ * Free all allocated descriptors associated with this channel
+ *
+ */
+static void adm_free_chan(struct dma_chan *chan)
+{
+	/* free all queued descriptors */
+	vchan_free_chan_resources(to_virt_chan(chan));
+}
+
+/**
+ * adm_get_blksize - Get block size from burst value
+ *
+ */
+static int adm_get_blksize(unsigned int burst)
+{
+	int ret;
+
+	switch (burst) {
+	case 16:
+	case 32:
+	case 64:
+	case 128:
+		ret = ffs(burst >> 4) - 1;
+		break;
+	case 192:
+		ret = 4;
+		break;
+	case 256:
+		ret = 5;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+/**
+ * adm_process_fc_descriptors - Process descriptors for flow controlled xfers
+ *
+ * @achan: ADM channel
+ * @desc: Descriptor memory pointer
+ * @sg: Scatterlist entry
+ * @crci: CRCI value
+ * @burst: Burst size of transaction
+ * @direction: DMA transfer direction
+ */
+static void *adm_process_fc_descriptors(struct adm_chan *achan, void *desc,
+					struct scatterlist *sg, u32 crci,
+					u32 burst,
+					enum dma_transfer_direction direction)
+{
+	struct adm_desc_hw_box *box_desc = NULL;
+	struct adm_desc_hw_single *single_desc;
+	u32 remainder = sg_dma_len(sg);
+	u32 rows, row_offset, crci_cmd;
+	u32 mem_addr = sg_dma_address(sg);
+	u32 *incr_addr = &mem_addr;
+	u32 *src, *dst;
+
+	if (direction == DMA_DEV_TO_MEM) {
+		crci_cmd = ADM_CMD_SRC_CRCI(crci);
+		row_offset = burst;
+		src = &achan->slave.src_addr;
+		dst = &mem_addr;
+	} else {
+		crci_cmd = ADM_CMD_DST_CRCI(crci);
+		row_offset = burst << 16;
+		src = &mem_addr;
+		dst = &achan->slave.dst_addr;
+	}
+
+	while (remainder >= burst) {
+		box_desc = desc;
+		box_desc->cmd = ADM_CMD_TYPE_BOX | crci_cmd;
+		box_desc->row_offset = row_offset;
+		box_desc->src_addr = *src;
+		box_desc->dst_addr = *dst;
+
+		rows = remainder / burst;
+		rows = min_t(u32, rows, ADM_MAX_ROWS);
+		box_desc->num_rows = rows << 16 | rows;
+		box_desc->row_len = burst << 16 | burst;
+
+		*incr_addr += burst * rows;
+		remainder -= burst * rows;
+		desc += sizeof(*box_desc);
+	}
+
+	/* if leftover bytes, do one single descriptor */
+	if (remainder) {
+		single_desc = desc;
+		single_desc->cmd = ADM_CMD_TYPE_SINGLE | crci_cmd;
+		single_desc->len = remainder;
+		single_desc->src_addr = *src;
+		single_desc->dst_addr = *dst;
+		desc += sizeof(*single_desc);
+
+		if (sg_is_last(sg))
+			single_desc->cmd |= ADM_CMD_LC;
+	} else {
+		if (box_desc && sg_is_last(sg))
+			box_desc->cmd |= ADM_CMD_LC;
+	}
+
+	return desc;
+}
+
+/**
+ * adm_process_non_fc_descriptors - Process descriptors for non-fc xfers
+ *
+ * @achan: ADM channel
+ * @desc: Descriptor memory pointer
+ * @sg: Scatterlist entry
+ * @direction: DMA transfer direction
+ */
+static void *adm_process_non_fc_descriptors(struct adm_chan *achan, void *desc,
+					    struct scatterlist *sg,
+					    enum dma_transfer_direction direction)
+{
+	struct adm_desc_hw_single *single_desc;
+	u32 remainder = sg_dma_len(sg);
+	u32 mem_addr = sg_dma_address(sg);
+	u32 *incr_addr = &mem_addr;
+	u32 *src, *dst;
+
+	if (direction == DMA_DEV_TO_MEM) {
+		src = &achan->slave.src_addr;
+		dst = &mem_addr;
+	} else {
+		src = &mem_addr;
+		dst = &achan->slave.dst_addr;
+	}
+
+	do {
+		single_desc = desc;
+		single_desc->cmd = ADM_CMD_TYPE_SINGLE;
+		single_desc->src_addr = *src;
+		single_desc->dst_addr = *dst;
+		single_desc->len = (remainder > ADM_MAX_XFER) ?
+				ADM_MAX_XFER : remainder;
+
+		remainder -= single_desc->len;
+		*incr_addr += single_desc->len;
+		desc += sizeof(*single_desc);
+	} while (remainder);
+
+	/* set last command if this is the end of the whole transaction */
+	if (sg_is_last(sg))
+		single_desc->cmd |= ADM_CMD_LC;
+
+	return desc;
+}
+
+/**
+ * adm_prep_slave_sg - Prep slave sg transaction
+ *
+ * @chan: dma channel
+ * @sgl: scatter gather list
+ * @sg_len: length of sg
+ * @direction: DMA transfer direction
+ * @flags: DMA flags
+ * @context: transfer context (unused)
+ */
+static struct dma_async_tx_descriptor *adm_prep_slave_sg(struct dma_chan *chan,
+							 struct scatterlist *sgl,
+							 unsigned int sg_len,
+							 enum dma_transfer_direction direction,
+							 unsigned long flags,
+							 void *context)
+{
+	struct adm_chan *achan = to_adm_chan(chan);
+	struct adm_device *adev = achan->adev;
+	struct adm_async_desc *async_desc;
+	struct scatterlist *sg;
+	dma_addr_t cple_addr;
+	u32 i, burst;
+	u32 single_count = 0, box_count = 0, crci = 0;
+	void *desc;
+	u32 *cple;
+	int blk_size = 0;
+
+	if (!is_slave_direction(direction)) {
+		dev_err(adev->dev, "invalid dma direction\n");
+		return NULL;
+	}
+
+	/*
+	 * get burst value from slave configuration
+	 */
+	burst = (direction == DMA_MEM_TO_DEV) ?
+		achan->slave.dst_maxburst :
+		achan->slave.src_maxburst;
+
+	/* if using flow control, validate burst and crci values */
+	if (achan->slave.device_fc) {
+		blk_size = adm_get_blksize(burst);
+		if (blk_size < 0) {
+			dev_err(adev->dev, "invalid burst value: %d\n",
+				burst);
+			return ERR_PTR(-EINVAL);
+		}
+
+		crci = achan->slave.slave_id & 0xf;
+		if (!crci || achan->slave.slave_id > 0x1f) {
+			dev_err(adev->dev, "invalid crci value\n");
+			return ERR_PTR(-EINVAL);
+		}
+	}
+
+	/* iterate through sgs and compute allocation size of structures */
+	for_each_sg(sgl, sg, sg_len, i) {
+		if (achan->slave.device_fc) {
+			box_count += DIV_ROUND_UP(sg_dma_len(sg) / burst,
+						  ADM_MAX_ROWS);
+			if (sg_dma_len(sg) % burst)
+				single_count++;
+		} else {
+			single_count += DIV_ROUND_UP(sg_dma_len(sg),
+						     ADM_MAX_XFER);
+		}
+	}
+
+	async_desc = kzalloc(sizeof(*async_desc), GFP_NOWAIT);
+	if (!async_desc)
+		return ERR_PTR(-ENOMEM);
+
+	if (crci)
+		async_desc->mux = achan->slave.slave_id & ADM_CRCI_MUX_SEL ?
+					ADM_CRCI_CTL_MUX_SEL : 0;
+	async_desc->crci = crci;
+	async_desc->blk_size = blk_size;
+	async_desc->dma_len = single_count * sizeof(struct adm_desc_hw_single) +
+				box_count * sizeof(struct adm_desc_hw_box) +
+				sizeof(*cple) + 2 * ADM_DESC_ALIGN;
+
+	async_desc->cpl = kzalloc(async_desc->dma_len, GFP_NOWAIT);
+	if (!async_desc->cpl)
+		goto free;
+
+	async_desc->adev = adev;
+
+	/* both command list entry and descriptors must be 8 byte aligned */
+	cple = PTR_ALIGN(async_desc->cpl, ADM_DESC_ALIGN);
+	desc = PTR_ALIGN(cple + 1, ADM_DESC_ALIGN);
+
+	for_each_sg(sgl, sg, sg_len, i) {
+		async_desc->length += sg_dma_len(sg);
+
+		if (achan->slave.device_fc)
+			desc = adm_process_fc_descriptors(achan, desc, sg, crci,
+							  burst, direction);
+		else
+			desc = adm_process_non_fc_descriptors(achan, desc, sg,
+							      direction);
+	}
+
+	async_desc->dma_addr = dma_map_single(adev->dev, async_desc->cpl,
+					      async_desc->dma_len,
+					      DMA_TO_DEVICE);
+	if (dma_mapping_error(adev->dev, async_desc->dma_addr))
+		goto free;
+
+	cple_addr = async_desc->dma_addr + ((void *)cple - async_desc->cpl);
+
+	/* init cmd list */
+	dma_sync_single_for_cpu(adev->dev, cple_addr, sizeof(*cple),
+				DMA_TO_DEVICE);
+	*cple = ADM_CPLE_LP;
+	*cple |= (async_desc->dma_addr + ADM_DESC_ALIGN) >> 3;
+	dma_sync_single_for_device(adev->dev, cple_addr, sizeof(*cple),
+				   DMA_TO_DEVICE);
+
+	return vchan_tx_prep(&achan->vc, &async_desc->vd, flags);
+
+free:
+	kfree(async_desc);
+	return ERR_PTR(-ENOMEM);
+}
+
+/**
+ * adm_terminate_all - terminate all transactions on a channel
+ * @achan: adm dma channel
+ *
+ * Dequeues and frees all transactions, aborts current transaction
+ * No callbacks are done
+ *
+ */
+static int adm_terminate_all(struct dma_chan *chan)
+{
+	struct adm_chan *achan = to_adm_chan(chan);
+	struct adm_device *adev = achan->adev;
+	unsigned long flags;
+	LIST_HEAD(head);
+
+	spin_lock_irqsave(&achan->vc.lock, flags);
+	vchan_get_all_descriptors(&achan->vc, &head);
+
+	/* send flush command to terminate current transaction */
+	writel_relaxed(0x0,
+		       adev->regs + ADM_CH_FLUSH_STATE0(achan->id, adev->ee));
+
+	spin_unlock_irqrestore(&achan->vc.lock, flags);
+
+	vchan_dma_desc_free_list(&achan->vc, &head);
+
+	return 0;
+}
+
+static int adm_slave_config(struct dma_chan *chan, struct dma_slave_config *cfg)
+{
+	struct adm_chan *achan = to_adm_chan(chan);
+	unsigned long flag;
+
+	spin_lock_irqsave(&achan->vc.lock, flag);
+	memcpy(&achan->slave, cfg, sizeof(struct dma_slave_config));
+	spin_unlock_irqrestore(&achan->vc.lock, flag);
+
+	return 0;
+}
+
+/**
+ * adm_start_dma - start next transaction
+ * @achan - ADM dma channel
+ */
+static void adm_start_dma(struct adm_chan *achan)
+{
+	struct virt_dma_desc *vd = vchan_next_desc(&achan->vc);
+	struct adm_device *adev = achan->adev;
+	struct adm_async_desc *async_desc;
+
+	lockdep_assert_held(&achan->vc.lock);
+
+	if (!vd)
+		return;
+
+	list_del(&vd->node);
+
+	/* write next command list out to the CMD FIFO */
+	async_desc = container_of(vd, struct adm_async_desc, vd);
+	achan->curr_txd = async_desc;
+
+	/* reset channel error */
+	achan->error = 0;
+
+	if (!achan->initialized) {
+		/* enable interrupts */
+		writel(ADM_CH_CONF_SHADOW_EN |
+		       ADM_CH_CONF_PERM_MPU_CONF |
+		       ADM_CH_CONF_MPU_DISABLE |
+		       ADM_CH_CONF_SEC_DOMAIN(adev->ee),
+		       adev->regs + ADM_CH_CONF(achan->id));
+
+		writel(ADM_CH_RSLT_CONF_IRQ_EN | ADM_CH_RSLT_CONF_FLUSH_EN,
+		       adev->regs + ADM_CH_RSLT_CONF(achan->id, adev->ee));
+
+		achan->initialized = 1;
+	}
+
+	/* set the crci block size if this transaction requires CRCI */
+	if (async_desc->crci) {
+		writel(async_desc->mux | async_desc->blk_size,
+		       adev->regs + ADM_CRCI_CTL(async_desc->crci, adev->ee));
+	}
+
+	/* make sure IRQ enable doesn't get reordered */
+	wmb();
+
+	/* write next command list out to the CMD FIFO */
+	writel(ALIGN(async_desc->dma_addr, ADM_DESC_ALIGN) >> 3,
+	       adev->regs + ADM_CH_CMD_PTR(achan->id, adev->ee));
+}
+
+/**
+ * adm_dma_irq - irq handler for ADM controller
+ * @irq: IRQ of interrupt
+ * @data: callback data
+ *
+ * IRQ handler for the bam controller
+ */
+static irqreturn_t adm_dma_irq(int irq, void *data)
+{
+	struct adm_device *adev = data;
+	u32 srcs, i;
+	struct adm_async_desc *async_desc;
+	unsigned long flags;
+
+	srcs = readl_relaxed(adev->regs +
+			ADM_SEC_DOMAIN_IRQ_STATUS(adev->ee));
+
+	for (i = 0; i < ADM_MAX_CHANNELS; i++) {
+		struct adm_chan *achan = &adev->channels[i];
+		u32 status, result;
+
+		if (srcs & BIT(i)) {
+			status = readl_relaxed(adev->regs +
+					       ADM_CH_STATUS_SD(i, adev->ee));
+
+			/* if no result present, skip */
+			if (!(status & ADM_CH_STATUS_VALID))
+				continue;
+
+			result = readl_relaxed(adev->regs +
+				ADM_CH_RSLT(i, adev->ee));
+
+			/* no valid results, skip */
+			if (!(result & ADM_CH_RSLT_VALID))
+				continue;
+
+			/* flag error if transaction was flushed or failed */
+			if (result & (ADM_CH_RSLT_ERR | ADM_CH_RSLT_FLUSH))
+				achan->error = 1;
+
+			spin_lock_irqsave(&achan->vc.lock, flags);
+			async_desc = achan->curr_txd;
+
+			achan->curr_txd = NULL;
+
+			if (async_desc) {
+				vchan_cookie_complete(&async_desc->vd);
+
+				/* kick off next DMA */
+				adm_start_dma(achan);
+			}
+
+			spin_unlock_irqrestore(&achan->vc.lock, flags);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * adm_tx_status - returns status of transaction
+ * @chan: dma channel
+ * @cookie: transaction cookie
+ * @txstate: DMA transaction state
+ *
+ * Return status of dma transaction
+ */
+static enum dma_status adm_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
+				     struct dma_tx_state *txstate)
+{
+	struct adm_chan *achan = to_adm_chan(chan);
+	struct virt_dma_desc *vd;
+	enum dma_status ret;
+	unsigned long flags;
+	size_t residue = 0;
+
+	ret = dma_cookie_status(chan, cookie, txstate);
+	if (ret == DMA_COMPLETE || !txstate)
+		return ret;
+
+	spin_lock_irqsave(&achan->vc.lock, flags);
+
+	vd = vchan_find_desc(&achan->vc, cookie);
+	if (vd)
+		residue = container_of(vd, struct adm_async_desc, vd)->length;
+
+	spin_unlock_irqrestore(&achan->vc.lock, flags);
+
+	/*
+	 * residue is either the full length if it is in the issued list, or 0
+	 * if it is in progress.  We have no reliable way of determining
+	 * anything inbetween
+	 */
+	dma_set_residue(txstate, residue);
+
+	if (achan->error)
+		return DMA_ERROR;
+
+	return ret;
+}
+
+/**
+ * adm_issue_pending - starts pending transactions
+ * @chan: dma channel
+ *
+ * Issues all pending transactions and starts DMA
+ */
+static void adm_issue_pending(struct dma_chan *chan)
+{
+	struct adm_chan *achan = to_adm_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&achan->vc.lock, flags);
+
+	if (vchan_issue_pending(&achan->vc) && !achan->curr_txd)
+		adm_start_dma(achan);
+	spin_unlock_irqrestore(&achan->vc.lock, flags);
+}
+
+/**
+ * adm_dma_free_desc - free descriptor memory
+ * @vd: virtual descriptor
+ *
+ */
+static void adm_dma_free_desc(struct virt_dma_desc *vd)
+{
+	struct adm_async_desc *async_desc = container_of(vd,
+			struct adm_async_desc, vd);
+
+	dma_unmap_single(async_desc->adev->dev, async_desc->dma_addr,
+			 async_desc->dma_len, DMA_TO_DEVICE);
+	kfree(async_desc->cpl);
+	kfree(async_desc);
+}
+
+static void adm_channel_init(struct adm_device *adev, struct adm_chan *achan,
+			     u32 index)
+{
+	achan->id = index;
+	achan->adev = adev;
+
+	vchan_init(&achan->vc, &adev->common);
+	achan->vc.desc_free = adm_dma_free_desc;
+}
+
+static int adm_dma_probe(struct platform_device *pdev)
+{
+	struct adm_device *adev;
+	int ret;
+	u32 i;
+
+	adev = devm_kzalloc(&pdev->dev, sizeof(*adev), GFP_KERNEL);
+	if (!adev)
+		return -ENOMEM;
+
+	adev->dev = &pdev->dev;
+
+	adev->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(adev->regs))
+		return PTR_ERR(adev->regs);
+
+	adev->irq = platform_get_irq(pdev, 0);
+	if (adev->irq < 0)
+		return adev->irq;
+
+	ret = of_property_read_u32(pdev->dev.of_node, "qcom,ee", &adev->ee);
+	if (ret) {
+		dev_err(adev->dev, "Execution environment unspecified\n");
+		return ret;
+	}
+
+	adev->core_clk = devm_clk_get(adev->dev, "core");
+	if (IS_ERR(adev->core_clk))
+		return PTR_ERR(adev->core_clk);
+
+	adev->iface_clk = devm_clk_get(adev->dev, "iface");
+	if (IS_ERR(adev->iface_clk))
+		return PTR_ERR(adev->iface_clk);
+
+	adev->clk_reset = devm_reset_control_get_exclusive(&pdev->dev, "clk");
+	if (IS_ERR(adev->clk_reset)) {
+		dev_err(adev->dev, "failed to get ADM0 reset\n");
+		return PTR_ERR(adev->clk_reset);
+	}
+
+	adev->c0_reset = devm_reset_control_get_exclusive(&pdev->dev, "c0");
+	if (IS_ERR(adev->c0_reset)) {
+		dev_err(adev->dev, "failed to get ADM0 C0 reset\n");
+		return PTR_ERR(adev->c0_reset);
+	}
+
+	adev->c1_reset = devm_reset_control_get_exclusive(&pdev->dev, "c1");
+	if (IS_ERR(adev->c1_reset)) {
+		dev_err(adev->dev, "failed to get ADM0 C1 reset\n");
+		return PTR_ERR(adev->c1_reset);
+	}
+
+	adev->c2_reset = devm_reset_control_get_exclusive(&pdev->dev, "c2");
+	if (IS_ERR(adev->c2_reset)) {
+		dev_err(adev->dev, "failed to get ADM0 C2 reset\n");
+		return PTR_ERR(adev->c2_reset);
+	}
+
+	ret = clk_prepare_enable(adev->core_clk);
+	if (ret) {
+		dev_err(adev->dev, "failed to prepare/enable core clock\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(adev->iface_clk);
+	if (ret) {
+		dev_err(adev->dev, "failed to prepare/enable iface clock\n");
+		goto err_disable_core_clk;
+	}
+
+	reset_control_assert(adev->clk_reset);
+	reset_control_assert(adev->c0_reset);
+	reset_control_assert(adev->c1_reset);
+	reset_control_assert(adev->c2_reset);
+
+	udelay(2);
+
+	reset_control_deassert(adev->clk_reset);
+	reset_control_deassert(adev->c0_reset);
+	reset_control_deassert(adev->c1_reset);
+	reset_control_deassert(adev->c2_reset);
+
+	adev->channels = devm_kcalloc(adev->dev, ADM_MAX_CHANNELS,
+				      sizeof(*adev->channels), GFP_KERNEL);
+
+	if (!adev->channels) {
+		ret = -ENOMEM;
+		goto err_disable_clks;
+	}
+
+	/* allocate and initialize channels */
+	INIT_LIST_HEAD(&adev->common.channels);
+
+	for (i = 0; i < ADM_MAX_CHANNELS; i++)
+		adm_channel_init(adev, &adev->channels[i], i);
+
+	/* reset CRCIs */
+	for (i = 0; i < 16; i++)
+		writel(ADM_CRCI_CTL_RST, adev->regs +
+			ADM_CRCI_CTL(i, adev->ee));
+
+	/* configure client interfaces */
+	writel(ADM_CI_RANGE_START(0x40) | ADM_CI_RANGE_END(0xb0) |
+	       ADM_CI_BURST_8_WORDS, adev->regs + ADM_CI_CONF(0));
+	writel(ADM_CI_RANGE_START(0x2a) | ADM_CI_RANGE_END(0x2c) |
+	       ADM_CI_BURST_8_WORDS, adev->regs + ADM_CI_CONF(1));
+	writel(ADM_CI_RANGE_START(0x12) | ADM_CI_RANGE_END(0x28) |
+	       ADM_CI_BURST_8_WORDS, adev->regs + ADM_CI_CONF(2));
+	writel(ADM_GP_CTL_LP_EN | ADM_GP_CTL_LP_CNT(0xf),
+	       adev->regs + ADM_GP_CTL);
+
+	ret = devm_request_irq(adev->dev, adev->irq, adm_dma_irq,
+			       0, "adm_dma", adev);
+	if (ret)
+		goto err_disable_clks;
+
+	platform_set_drvdata(pdev, adev);
+
+	adev->common.dev = adev->dev;
+	adev->common.dev->dma_parms = &adev->dma_parms;
+
+	/* set capabilities */
+	dma_cap_zero(adev->common.cap_mask);
+	dma_cap_set(DMA_SLAVE, adev->common.cap_mask);
+	dma_cap_set(DMA_PRIVATE, adev->common.cap_mask);
+
+	/* initialize dmaengine apis */
+	adev->common.directions = BIT(DMA_DEV_TO_MEM | DMA_MEM_TO_DEV);
+	adev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+	adev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	adev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	adev->common.device_free_chan_resources = adm_free_chan;
+	adev->common.device_prep_slave_sg = adm_prep_slave_sg;
+	adev->common.device_issue_pending = adm_issue_pending;
+	adev->common.device_tx_status = adm_tx_status;
+	adev->common.device_terminate_all = adm_terminate_all;
+	adev->common.device_config = adm_slave_config;
+
+	ret = dma_async_device_register(&adev->common);
+	if (ret) {
+		dev_err(adev->dev, "failed to register dma async device\n");
+		goto err_disable_clks;
+	}
+
+	ret = of_dma_controller_register(pdev->dev.of_node,
+					 of_dma_xlate_by_chan_id,
+					 &adev->common);
+	if (ret)
+		goto err_unregister_dma;
+
+	return 0;
+
+err_unregister_dma:
+	dma_async_device_unregister(&adev->common);
+err_disable_clks:
+	clk_disable_unprepare(adev->iface_clk);
+err_disable_core_clk:
+	clk_disable_unprepare(adev->core_clk);
+
+	return ret;
+}
+
+static int adm_dma_remove(struct platform_device *pdev)
+{
+	struct adm_device *adev = platform_get_drvdata(pdev);
+	struct adm_chan *achan;
+	u32 i;
+
+	of_dma_controller_free(pdev->dev.of_node);
+	dma_async_device_unregister(&adev->common);
+
+	for (i = 0; i < ADM_MAX_CHANNELS; i++) {
+		achan = &adev->channels[i];
+
+		/* mask IRQs for this channel/EE pair */
+		writel(0, adev->regs + ADM_CH_RSLT_CONF(achan->id, adev->ee));
+
+		tasklet_kill(&adev->channels[i].vc.task);
+		adm_terminate_all(&adev->channels[i].vc.chan);
+	}
+
+	devm_free_irq(adev->dev, adev->irq, adev);
+
+	clk_disable_unprepare(adev->core_clk);
+	clk_disable_unprepare(adev->iface_clk);
+
+	return 0;
+}
+
+static const struct of_device_id adm_of_match[] = {
+	{ .compatible = "qcom,adm", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, adm_of_match);
+
+static struct platform_driver adm_dma_driver = {
+	.probe = adm_dma_probe,
+	.remove = adm_dma_remove,
+	.driver = {
+		.name = "adm-dma-engine",
+		.of_match_table = adm_of_match,
+	},
+};
+
+module_platform_driver(adm_dma_driver);
+
+MODULE_AUTHOR("Andy Gross <agross@...eaurora.org>");
+MODULE_DESCRIPTION("QCOM ADM DMA engine driver");
+MODULE_LICENSE("GPL v2");
-- 
2.20.1

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