[RFC PATCH 2/5] RFC: msm: sps: BAM-DMA driver

Kenneth Heitke kheitke at codeaurora.org
Mon Feb 28 20:11:29 EST 2011


From: Amir Samuelovi <amirs at codeaurora.org>

The BAM-DMA is a Bus Access Manager (BAM) hardware block specifically
for data transfers from memory to memory rather than being associated
with a peripheral core (like other BAMs).

Signed-off-by: Amir Samuelov <amirs at codeaurora.org>
Signed-off-by: Kenneth Heitke <kheitke at codeaurora.org>
---
 arch/arm/mach-msm/sps/sps_dma.c |  896 +++++++++++++++++++++++++++++++++++++++
 1 files changed, 896 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/mach-msm/sps/sps_dma.c

diff --git a/arch/arm/mach-msm/sps/sps_dma.c b/arch/arm/mach-msm/sps/sps_dma.c
new file mode 100644
index 0000000..9179ed9
--- /dev/null
+++ b/arch/arm/mach-msm/sps/sps_dma.c
@@ -0,0 +1,896 @@
+/* Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+/* BAM-DMA Manager. */
+
+#ifdef CONFIG_SPS_SUPPORT_BAMDMA
+
+#include <linux/memory.h>	/* memset */
+
+#include "spsi.h"
+#include "bam.h"
+#include "sps_bam.h"		/* bam_dma_thresh_dma */
+#include "sps_core.h"		/* sps_h2bam() */
+
+/**
+ * registers
+ */
+
+#define DMA_ENBL			(0x00000000)
+#define DMA_CHNL_CONFIG(n)		(0x00000004 + 4 * (n))
+#define DMA_CONFIG			(0x00000040)
+
+/**
+ * masks
+ */
+
+/* DMA_CHNL_confign */
+#define DMA_CHNL_HALT_DONE		0x10000
+#define DMA_CHNL_HALT			0x1000
+#define DMA_CHNL_ENABLE                 0x100
+#define DMA_CHNL_ACT_THRESH             0x30
+#define DMA_CHNL_WEIGHT                 0x7
+
+/* DMA_CONFIG */
+#define TESTBUS_SELECT                  0x3
+
+/**
+ *
+ * Write register with debug info.
+ *
+ * @base - bam base virtual address.
+ * @offset - register offset.
+ * @val - value to write.
+ *
+ */
+static inline void dma_write_reg(void *base, u32 offset, u32 val)
+{
+	iowrite32(val, base + offset);
+	SPS_DBG("bamdma: write reg 0x%x w_val 0x%x.", offset, val);
+}
+
+/**
+ * Write register masked field with debug info.
+ *
+ * @base - bam base virtual address.
+ * @offset - register offset.
+ * @mask - register bitmask.
+ * @val - value to write.
+ *
+ */
+static inline void dma_write_reg_field(void *base, u32 offset,
+				       const u32 mask, u32 val)
+{
+	u32 shift = find_first_bit((void *)&mask, 32);
+	u32 tmp = ioread32(base + offset);
+
+	tmp &= ~mask;		/* clear written bits */
+	val = tmp | (val << shift);
+	iowrite32(val, base + offset);
+	SPS_DBG("bamdma: write reg 0x%x w_val 0x%x.", offset, val);
+}
+
+/* Round max number of pipes to nearest multiple of 2 */
+#define DMA_MAX_PIPES         ((BAM_MAX_PIPES / 2) * 2)
+
+/* Maximum number of BAM-DMAs supported */
+#define MAX_BAM_DMA_DEVICES   1
+
+/* Maximum number of BAMs that will be registered */
+#define MAX_BAM_DMA_BAMS      1
+
+/* Pipe enable check values */
+#define DMA_PIPES_STATE_DIFF     0
+#define DMA_PIPES_BOTH_DISABLED  1
+#define DMA_PIPES_BOTH_ENABLED   2
+
+/* Even pipe is tx/dest/input/write, odd pipe is rx/src/output/read */
+#define DMA_PIPE_IS_DEST(p)   (((p) & 1) == 0)
+#define DMA_PIPE_IS_SRC(p)    (((p) & 1) != 0)
+
+/* BAM DMA pipe state */
+enum bamdma_pipe_state {
+	PIPE_INACTIVE = 0,
+	PIPE_ACTIVE
+};
+
+/* BAM DMA channel state */
+enum bamdma_chan_state {
+	DMA_CHAN_STATE_FREE = 0,
+	DMA_CHAN_STATE_ALLOC_EXT,	/* Client allocation */
+	DMA_CHAN_STATE_ALLOC_INT	/* Internal (resource mgr) allocation */
+};
+
+struct bamdma_chan {
+	/* Allocation state */
+	enum bamdma_chan_state state;
+
+	/* BAM DMA channel configuration parameters */
+	u32 threshold;
+	enum sps_dma_priority priority;
+
+	/* HWIO channel configuration parameters */
+	enum bam_dma_thresh_dma thresh;
+	enum bam_dma_weight_dma weight;
+
+};
+
+/* BAM DMA device state */
+struct bamdma_device {
+	/* BAM-DMA device state */
+	int enabled;
+	int local;
+
+	/* BAM device state */
+	struct sps_bam *bam;
+
+	/* BAM handle, for deregistration */
+	u32 h;
+
+	/* BAM DMA device virtual mapping */
+	void *virt_addr;
+	int virtual_mapped;
+	u32 phys_addr;
+	void *hwio;
+
+	/* BAM DMA pipe/channel state */
+	u32 num_pipes;
+	enum bamdma_pipe_state pipes[DMA_MAX_PIPES];
+	struct bamdma_chan chans[DMA_MAX_PIPES / 2];
+
+};
+
+/* BAM-DMA devices */
+static struct bamdma_device bam_dma_dev[MAX_BAM_DMA_DEVICES];
+static struct mutex bam_dma_lock;
+
+/*
+ * The BAM DMA module registers all BAMs in the BSP properties, but only
+ * uses the first BAM-DMA device for allocations.  References to the others
+ * are stored in the following data array.
+ */
+static int num_bams;
+static u32 bam_handles[MAX_BAM_DMA_BAMS];
+
+/**
+ * Find BAM-DMA device
+ *
+ * This function finds the BAM-DMA device associated with the BAM handle.
+ *
+ * @h - BAM handle
+ *
+ * @return - pointer to BAM-DMA device, or NULL on error
+ *
+ */
+static struct bamdma_device *sps_dma_find_device(u32 h)
+{
+	return &bam_dma_dev[0];
+}
+
+/**
+ * BAM DMA device enable
+ *
+ * This function enables a BAM DMA device and the associated BAM.
+ *
+ * @dev - pointer to BAM DMA device context
+ *
+ * @return 0 on success, negative value on error
+ *
+ */
+static int sps_dma_device_enable(struct bamdma_device *dev)
+{
+	if (dev->enabled)
+		return 0;
+
+	/*
+	 *  If the BAM-DMA device is locally controlled then enable BAM-DMA
+	 *  device
+	 */
+	if (dev->local)
+		dma_write_reg(dev->virt_addr, DMA_ENBL, 1);
+
+	/* Enable BAM device */
+	if (sps_bam_enable(dev->bam)) {
+		SPS_ERR("Failed to enable BAM DMA's BAM: %x", dev->phys_addr);
+		return SPS_ERROR;
+	}
+
+	dev->enabled = true;
+
+	return 0;
+}
+
+/**
+ * BAM DMA device enable
+ *
+ * This function initializes a BAM DMA device.
+ *
+ * @dev - pointer to BAM DMA device context
+ *
+ * @return 0 on success, negative value on error
+ *
+ */
+static int sps_dma_device_disable(struct bamdma_device *dev)
+{
+	u32 pipe_index;
+
+	if (!dev->enabled)
+		return 0;
+
+	/* Do not disable if channels active */
+	for (pipe_index = 0; pipe_index < dev->num_pipes; pipe_index++) {
+		if (dev->pipes[pipe_index] != PIPE_INACTIVE)
+			break;
+	}
+
+	if (pipe_index < dev->num_pipes) {
+		SPS_ERR("Failed to disable BAM-DMA %x: channels are active",
+			dev->phys_addr);
+		return SPS_ERROR;
+	}
+
+	dev->enabled = false;
+
+	/* Disable BAM device */
+	if (sps_bam_disable(dev->bam)) {
+		SPS_ERR("Failed to disable BAM-DMA %x BAM", dev->phys_addr);
+		return SPS_ERROR;
+	}
+
+	/* Is the BAM-DMA device locally controlled? */
+	if (dev->local)
+		/* Disable BAM-DMA device */
+		dma_write_reg(dev->virt_addr, DMA_ENBL, 0);
+
+	return 0;
+}
+
+/**
+ * Initialize BAM DMA device
+ *
+ */
+int sps_dma_device_init(u32 h)
+{
+	struct bamdma_device *dev;
+	struct sps_bam_props *props;
+	u32 chan;
+	int result = SPS_ERROR;
+
+	mutex_lock(&bam_dma_lock);
+
+	/* Find a free BAM-DMA device slot */
+	dev = NULL;
+	if (bam_dma_dev[0].bam != NULL) {
+		SPS_ERR("BAM-DMA BAM device already initialized.");
+		goto exit_err;
+	} else {
+		dev = &bam_dma_dev[0];
+	}
+
+	/* Record BAM */
+	memset(dev, 0, sizeof(*dev));
+	dev->h = h;
+	dev->bam = sps_h2bam(h);
+
+	/* Map the BAM DMA device into virtual space, if necessary */
+	props = &dev->bam->props;
+	dev->phys_addr = props->periph_phys_addr;
+	if (props->periph_virt_addr != NULL) {
+		dev->virt_addr = props->periph_virt_addr;
+		dev->virtual_mapped = false;
+	} else {
+		if (props->periph_virt_size == 0) {
+			SPS_ERR("Unable to map BAM DMA IO memory: %x %x",
+			 dev->phys_addr, props->periph_virt_size);
+			goto exit_err;
+		}
+
+		dev->virt_addr = ioremap(dev->phys_addr,
+					  props->periph_virt_size);
+		if (dev->virt_addr == NULL) {
+			SPS_ERR("Unable to map BAM DMA IO memory: %x %x",
+				dev->phys_addr, props->periph_virt_size);
+			goto exit_err;
+		}
+		dev->virtual_mapped = true;
+	}
+	dev->hwio = (void *) dev->virt_addr;
+
+	/* Is the BAM-DMA device locally controlled? */
+	if ((props->manage & SPS_BAM_MGR_DEVICE_REMOTE) == 0) {
+		SPS_DBG("BAM-DMA is controlled locally: %x",
+			dev->phys_addr);
+		dev->local = true;
+	} else {
+		SPS_DBG("BAM-DMA is controlled remotely: %x",
+			dev->phys_addr);
+		dev->local = false;
+	}
+
+	/*
+	 * Enable the BAM DMA and determine the number of pipes/channels.
+	 * Leave the BAM-DMA enabled, since it is always a shared device.
+	 */
+	if (sps_dma_device_enable(dev))
+		goto exit_err;
+
+	dev->num_pipes = dev->bam->props.num_pipes;
+
+	/* Disable all channels */
+	if (dev->local)
+		for (chan = 0; chan < (dev->num_pipes / 2); chan++) {
+			dma_write_reg_field(dev->virt_addr,
+					    DMA_CHNL_CONFIG(chan),
+					    DMA_CHNL_ENABLE, 0);
+		}
+
+	result = 0;
+exit_err:
+	if (result) {
+		if (dev != NULL) {
+			if (dev->virtual_mapped)
+				iounmap(dev->virt_addr);
+
+			dev->bam = NULL;
+		}
+	}
+
+	mutex_unlock(&bam_dma_lock);
+
+	return result;
+}
+
+/**
+ * De-initialize BAM DMA device
+ *
+ */
+int sps_dma_device_de_init(u32 h)
+{
+	struct bamdma_device *dev;
+	u32 pipe_index;
+	u32 chan;
+	int result = 0;
+
+	mutex_lock(&bam_dma_lock);
+
+	dev = sps_dma_find_device(h);
+	if (dev == NULL) {
+		SPS_ERR("BAM-DMA: not registered: %x", h);
+		result = SPS_ERROR;
+		goto exit_err;
+	}
+
+	/* Check for channel leaks */
+	for (chan = 0; chan < dev->num_pipes / 2; chan++) {
+		if (dev->chans[chan].state != DMA_CHAN_STATE_FREE) {
+			SPS_ERR("BAM-DMA: channel not free: %d", chan);
+			result = SPS_ERROR;
+			dev->chans[chan].state = DMA_CHAN_STATE_FREE;
+		}
+	}
+	for (pipe_index = 0; pipe_index < dev->num_pipes; pipe_index++) {
+		if (dev->pipes[pipe_index] != PIPE_INACTIVE) {
+			SPS_ERR("BAM-DMA: pipe not inactive: %d", pipe_index);
+			result = SPS_ERROR;
+			dev->pipes[pipe_index] = PIPE_INACTIVE;
+		}
+	}
+
+	/* Disable BAM and BAM-DMA */
+	if (sps_dma_device_disable(dev))
+		result = SPS_ERROR;
+
+	dev->h = BAM_HANDLE_INVALID;
+	dev->bam = NULL;
+	if (dev->virtual_mapped)
+		iounmap(dev->virt_addr);
+
+exit_err:
+	mutex_unlock(&bam_dma_lock);
+
+	return result;
+}
+
+/**
+ * Initialize BAM DMA module
+ *
+ */
+int sps_dma_init(const struct sps_bam_props *bam_props)
+{
+	struct sps_bam_props props;
+	const struct sps_bam_props *bam_reg;
+	u32 h;
+
+	/* Init local data */
+	memset(&bam_dma_dev, 0, sizeof(bam_dma_dev));
+	num_bams = 0;
+	memset(bam_handles, 0, sizeof(bam_handles));
+
+	/* Create a mutex to control access to the BAM-DMA devices */
+	mutex_init(&bam_dma_lock);
+
+	/* Are there any BAM DMA devices? */
+	if (bam_props == NULL)
+		return 0;
+
+	/*
+	 * Registers all BAMs in the BSP properties, but only uses the first
+	 * BAM-DMA device for allocations.
+	 */
+	if (bam_props->phys_addr) {
+		/* Force multi-EE option for all BAM-DMAs */
+		bam_reg = bam_props;
+		if ((bam_props->options & SPS_BAM_OPT_BAMDMA) &&
+		    (bam_props->manage & SPS_BAM_MGR_MULTI_EE) == 0) {
+			SPS_DBG("Setting multi-EE options for BAM-DMA: %x",
+				bam_props->phys_addr);
+			props = *bam_props;
+			props.manage |= SPS_BAM_MGR_MULTI_EE;
+			bam_reg = &props;
+		}
+
+		/* Register the BAM */
+		if (sps_register_bam_device(bam_reg, &h)) {
+			SPS_ERR("Failed to register BAM-DMA BAM device: "
+				"phys 0x%0x", bam_props->phys_addr);
+			return SPS_ERROR;
+		}
+
+		/* Record the BAM so that it may be deregistered later */
+		if (num_bams < MAX_BAM_DMA_BAMS) {
+			bam_handles[num_bams] = h;
+			num_bams++;
+		} else {
+			SPS_ERR("BAM-DMA: BAM limit exceeded: %d", num_bams);
+			return SPS_ERROR;
+		}
+	} else {
+		SPS_ERR("BAM-DMA phys_addr is zero.");
+		return SPS_ERROR;
+	}
+
+
+	return 0;
+}
+
+/**
+ * De-initialize BAM DMA module
+ *
+ */
+void sps_dma_de_init(void)
+{
+	int n;
+
+	/* De-initialize the BAM devices */
+	for (n = 0; n < num_bams; n++)
+		sps_deregister_bam_device(bam_handles[n]);
+
+	/* Clear local data */
+	memset(&bam_dma_dev, 0, sizeof(bam_dma_dev));
+	num_bams = 0;
+	memset(bam_handles, 0, sizeof(bam_handles));
+}
+
+/**
+ * Allocate a BAM DMA channel
+ *
+ */
+int sps_alloc_dma_chan(const struct sps_alloc_dma_chan *alloc,
+		       struct sps_dma_chan *chan_info)
+{
+	struct bamdma_device *dev;
+	struct bamdma_chan *chan;
+	u32 pipe_index;
+	enum bam_dma_thresh_dma thresh = (enum bam_dma_thresh_dma) 0;
+	enum bam_dma_weight_dma weight = (enum bam_dma_weight_dma) 0;
+	int result = SPS_ERROR;
+
+	if (alloc == NULL || chan_info == NULL) {
+		SPS_ERR("sps_alloc_dma_chan. invalid parameters");
+		return SPS_ERROR;
+	}
+
+	/* Translate threshold and priority to hwio values */
+	if (alloc->threshold != SPS_DMA_THRESHOLD_DEFAULT) {
+		if (alloc->threshold >= 512)
+			thresh = BAM_DMA_THRESH_512;
+		else if (alloc->threshold >= 256)
+			thresh = BAM_DMA_THRESH_256;
+		else if (alloc->threshold >= 128)
+			thresh = BAM_DMA_THRESH_128;
+		else
+			thresh = BAM_DMA_THRESH_64;
+	}
+
+	weight = alloc->priority;
+
+	if (alloc->priority > BAM_DMA_WEIGHT_HIGH) {
+		SPS_ERR("BAM-DMA: invalid priority: %x", alloc->priority);
+		return SPS_ERROR;
+	}
+
+	mutex_lock(&bam_dma_lock);
+
+	dev = sps_dma_find_device(alloc->dev);
+	if (dev == NULL) {
+		SPS_ERR("BAM-DMA: invalid BAM handle: %x", alloc->dev);
+		goto exit_err;
+	}
+
+	/* Search for a free set of pipes */
+	for (pipe_index = 0, chan = dev->chans;
+	      pipe_index < dev->num_pipes; pipe_index += 2, chan++) {
+		if (chan->state == DMA_CHAN_STATE_FREE) {
+			/* Just check pipes for safety */
+			if (dev->pipes[pipe_index] != PIPE_INACTIVE ||
+			    dev->pipes[pipe_index + 1] != PIPE_INACTIVE) {
+				SPS_ERR("BAM-DMA: channel %d state error:%d %d",
+					pipe_index / 2, dev->pipes[pipe_index],
+				 dev->pipes[pipe_index + 1]);
+				goto exit_err;
+			}
+			break; /* Found free pipe */
+		}
+	}
+
+	if (pipe_index >= dev->num_pipes) {
+		SPS_ERR("BAM-DMA: no free channel. num_pipes = %d",
+			dev->num_pipes);
+		goto exit_err;
+	}
+
+	chan->state = DMA_CHAN_STATE_ALLOC_EXT;
+
+	/* Store config values for use when pipes are activated */
+	chan = &dev->chans[pipe_index / 2];
+	chan->threshold = alloc->threshold;
+	chan->thresh = thresh;
+	chan->priority = alloc->priority;
+	chan->weight = weight;
+
+	SPS_DBG("sps_alloc_dma_chan. pipe %d.\n", pipe_index);
+
+	/* Report allocated pipes to client */
+	chan_info->dev = dev->h;
+	/* Dest/input/write pipex */
+	chan_info->dest_pipe_index = pipe_index;
+	/* Source/output/read pipe */
+	chan_info->src_pipe_index = pipe_index + 1;
+
+	result = 0;
+exit_err:
+	mutex_unlock(&bam_dma_lock);
+
+	return result;
+}
+EXPORT_SYMBOL(sps_alloc_dma_chan);
+
+/**
+ * Free a BAM DMA channel
+ *
+ */
+int sps_free_dma_chan(struct sps_dma_chan *chan)
+{
+	struct bamdma_device *dev;
+	u32 pipe_index;
+	int result = 0;
+
+	if (chan == NULL) {
+		SPS_ERR("sps_free_dma_chan. chan is NULL");
+		return SPS_ERROR;
+	}
+
+	mutex_lock(&bam_dma_lock);
+
+	dev = sps_dma_find_device(chan->dev);
+	if (dev == NULL) {
+		SPS_ERR("BAM-DMA: invalid BAM handle: %x", chan->dev);
+		result = SPS_ERROR;
+		goto exit_err;
+	}
+
+	/* Verify the pipe indices */
+	pipe_index = chan->dest_pipe_index;
+	if (pipe_index >= dev->num_pipes || ((pipe_index & 1)) ||
+	    (pipe_index + 1) != chan->src_pipe_index) {
+		SPS_ERR("sps_free_dma_chan. Invalid pipe indices");
+		SPS_DBG("num_pipes=%d.dest=%d.src=%d.",
+			dev->num_pipes,
+			chan->dest_pipe_index,
+			chan->src_pipe_index);
+		result = SPS_ERROR;
+		goto exit_err;
+	}
+
+	/* Are both pipes inactive? */
+	if (dev->chans[pipe_index / 2].state != DMA_CHAN_STATE_ALLOC_EXT ||
+	    dev->pipes[pipe_index] != PIPE_INACTIVE ||
+	    dev->pipes[pipe_index + 1] != PIPE_INACTIVE) {
+		SPS_ERR("BAM-DMA: attempt to free active chan %d: %d %d",
+			pipe_index / 2, dev->pipes[pipe_index],
+			dev->pipes[pipe_index + 1]);
+		result = SPS_ERROR;
+		goto exit_err;
+	}
+
+	/* Free the channel */
+	dev->chans[pipe_index / 2].state = DMA_CHAN_STATE_FREE;
+
+exit_err:
+	mutex_unlock(&bam_dma_lock);
+
+	return result;
+}
+EXPORT_SYMBOL(sps_free_dma_chan);
+
+/**
+ * Activate a BAM DMA pipe
+ *
+ * This function activates a BAM DMA pipe.
+ *
+ * @dev - pointer to BAM-DMA device descriptor
+ *
+ * @pipe_index - pipe index
+ *
+ * @return 0 on success, negative value on error
+ *
+ */
+static u32 sps_dma_check_pipes(struct bamdma_device *dev, u32 pipe_index)
+{
+	u32 pipe_in;
+	u32 pipe_out;
+	int enabled_in;
+	int enabled_out;
+	u32 check;
+
+	pipe_in = pipe_index & ~1;
+	pipe_out = pipe_in + 1;
+	enabled_in = bam_pipe_is_enabled(dev->bam->base, pipe_in);
+	enabled_out = bam_pipe_is_enabled(dev->bam->base, pipe_out);
+
+	if (!enabled_in && !enabled_out)
+		check = DMA_PIPES_BOTH_DISABLED;
+	else if (enabled_in && enabled_out)
+		check = DMA_PIPES_BOTH_ENABLED;
+	else
+		check = DMA_PIPES_STATE_DIFF;
+
+	return check;
+}
+
+/**
+ * Allocate a BAM DMA pipe
+ *
+ */
+int sps_dma_pipe_alloc(void *bam_arg, u32 pipe_index, enum sps_mode dir)
+{
+	struct sps_bam *bam = bam_arg;
+	struct bamdma_device *dev;
+	struct bamdma_chan *chan;
+	u32 channel;
+	int result = SPS_ERROR;
+
+	if (bam == NULL) {
+		SPS_ERR("BAM context is NULL");
+		return SPS_ERROR;
+	}
+
+	/* Check pipe direction */
+	if ((DMA_PIPE_IS_DEST(pipe_index) && dir != SPS_MODE_DEST) ||
+	    (DMA_PIPE_IS_SRC(pipe_index) && dir != SPS_MODE_SRC)) {
+		SPS_ERR("BAM-DMA: wrong direction for BAM %x pipe %d",
+			bam->props.phys_addr, pipe_index);
+		return SPS_ERROR;
+	}
+
+	mutex_lock(&bam_dma_lock);
+
+	dev = sps_dma_find_device((u32) bam);
+	if (dev == NULL) {
+		SPS_ERR("BAM-DMA: invalid BAM: %x",
+			bam->props.phys_addr);
+		goto exit_err;
+	}
+	if (pipe_index >= dev->num_pipes) {
+		SPS_ERR("BAM-DMA: BAM %x invalid pipe: %d",
+			bam->props.phys_addr, pipe_index);
+		goto exit_err;
+	}
+	if (dev->pipes[pipe_index] != PIPE_INACTIVE) {
+		SPS_ERR("BAM-DMA: BAM %x pipe %d already active",
+			bam->props.phys_addr, pipe_index);
+		goto exit_err;
+	}
+
+	/* Mark pipe active */
+	dev->pipes[pipe_index] = PIPE_ACTIVE;
+
+	/* If channel is not allocated, make an internal allocation */
+	channel = pipe_index / 2;
+	chan = &dev->chans[channel];
+	if (chan->state != DMA_CHAN_STATE_ALLOC_EXT &&
+	    chan->state != DMA_CHAN_STATE_ALLOC_INT) {
+		chan->state = DMA_CHAN_STATE_ALLOC_INT;
+	}
+
+	result = 0;
+exit_err:
+	mutex_unlock(&bam_dma_lock);
+
+	return result;
+}
+
+/**
+ * Enable a BAM DMA pipe
+ *
+ */
+int sps_dma_pipe_enable(void *bam_arg, u32 pipe_index)
+{
+	struct sps_bam *bam = bam_arg;
+	struct bamdma_device *dev;
+	struct bamdma_chan *chan;
+	u32 channel;
+	int result = SPS_ERROR;
+
+	SPS_DBG("sps_dma_pipe_enable.pipe %d", pipe_index);
+
+	mutex_lock(&bam_dma_lock);
+
+	dev = sps_dma_find_device((u32) bam);
+	if (dev == NULL) {
+		SPS_ERR("BAM-DMA: invalid BAM");
+		goto exit_err;
+	}
+	if (pipe_index >= dev->num_pipes) {
+		SPS_ERR("BAM-DMA: BAM %x invalid pipe: %d",
+			bam->props.phys_addr, pipe_index);
+		goto exit_err;
+	}
+	if (dev->pipes[pipe_index] != PIPE_ACTIVE) {
+		SPS_ERR("BAM-DMA: BAM %x pipe %d not active",
+			bam->props.phys_addr, pipe_index);
+		goto exit_err;
+	}
+
+      /*
+       * The channel must be enabled when the dest/input/write pipe
+       * is enabled
+       */
+	if (DMA_PIPE_IS_DEST(pipe_index)) {
+		/* Configure and enable the channel */
+		channel = pipe_index / 2;
+		chan = &dev->chans[channel];
+
+		if (chan->threshold != SPS_DMA_THRESHOLD_DEFAULT)
+			dma_write_reg_field(dev->virt_addr,
+					    DMA_CHNL_CONFIG(channel),
+					    DMA_CHNL_ACT_THRESH,
+					    chan->thresh);
+
+		if (chan->priority != SPS_DMA_PRI_DEFAULT)
+			dma_write_reg_field(dev->virt_addr,
+					    DMA_CHNL_CONFIG(channel),
+					    DMA_CHNL_WEIGHT,
+					    chan->weight);
+
+		dma_write_reg_field(dev->virt_addr,
+				    DMA_CHNL_CONFIG(channel),
+				    DMA_CHNL_ENABLE, 1);
+	}
+
+	result = 0;
+exit_err:
+	mutex_unlock(&bam_dma_lock);
+
+	return result;
+}
+
+/**
+ * Deactivate a BAM DMA pipe
+ *
+ * This function deactivates a BAM DMA pipe.
+ *
+ * @dev - pointer to BAM-DMA device descriptor
+ *
+ * @bam - pointer to BAM device descriptor
+ *
+ * @pipe_index - pipe index
+ *
+ * @return 0 on success, negative value on error
+ *
+ */
+static int sps_dma_deactivate_pipe_atomic(struct bamdma_device *dev,
+					  struct sps_bam *bam,
+					  u32 pipe_index)
+{
+	u32 channel;
+
+	if (dev->bam != bam)
+		return SPS_ERROR;
+	if (pipe_index >= dev->num_pipes)
+		return SPS_ERROR;
+	if (dev->pipes[pipe_index] != PIPE_ACTIVE)
+		return SPS_ERROR;	/* Pipe is not active */
+
+	SPS_DBG("BAM-DMA: deactivate pipe %d", pipe_index);
+
+	/* Mark pipe inactive */
+	dev->pipes[pipe_index] = PIPE_INACTIVE;
+
+	/*
+	 * Channel must be reset when either pipe is disabled, so just always
+	 * reset regardless of other pipe's state
+	 */
+	channel = pipe_index / 2;
+	dma_write_reg_field(dev->virt_addr, DMA_CHNL_CONFIG(channel),
+			    DMA_CHNL_ENABLE, 0);
+
+	/* If the peer pipe is also inactive, reset the channel */
+	if (sps_dma_check_pipes(dev, pipe_index) == DMA_PIPES_BOTH_DISABLED) {
+		/* Free channel if allocated internally */
+		if (dev->chans[channel].state == DMA_CHAN_STATE_ALLOC_INT)
+			dev->chans[channel].state = DMA_CHAN_STATE_FREE;
+	}
+
+	return 0;
+}
+
+/**
+ * Free a BAM DMA pipe
+ *
+ */
+int sps_dma_pipe_free(void *bam_arg, u32 pipe_index)
+{
+	struct bamdma_device *dev;
+	struct sps_bam *bam = bam_arg;
+	int result;
+
+	mutex_lock(&bam_dma_lock);
+
+	dev = sps_dma_find_device((u32) bam);
+	if (dev == NULL) {
+		SPS_ERR("BAM-DMA: invalid BAM");
+		result = SPS_ERROR;
+		goto exit_err;
+	}
+
+	result = sps_dma_deactivate_pipe_atomic(dev, bam, pipe_index);
+
+exit_err:
+	mutex_unlock(&bam_dma_lock);
+
+	return result;
+}
+
+/**
+ * Get the BAM handle for BAM-DMA.
+ *
+ * The BAM handle should be use as source/destination in the sps_connect().
+ *
+ * @return bam handle on success, zero on error
+ */
+u32 sps_dma_get_bam_handle(void)
+{
+	return (u32) bam_dma_dev[0].bam;
+}
+EXPORT_SYMBOL(sps_dma_get_bam_handle);
+
+/**
+ * Free the BAM handle for BAM-DMA.
+ *
+ */
+void sps_dma_free_bam_handle(u32 h)
+{
+}
+EXPORT_SYMBOL(sps_dma_free_bam_handle);
+
+#endif /* CONFIG_SPS_SUPPORT_BAMDMA */
-- 
1.7.3.3

Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.



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