1 files changed, 642 insertions, 0 deletions

diff --git a/target/linux/brcm2708/patches-3.14/0033-dmaengine-Add-support-for-BCM2708.patch b/target/linux/brcm2708/patches-3.14/0033-dmaengine-Add-support-for-BCM2708.patch
new file mode 100644
index 0000000000..320589a827
--- /dev/null
+++ b/target/linux/brcm2708/patches-3.14/0033-dmaengine-Add-support-for-BCM2708.patch
@@ -0,0 +1,642 @@
+From 568b7292b8e7e1fe3d852db8b463d989d06b5adf Mon Sep 17 00:00:00 2001
+From: Florian Meier <florian.meier@koalo.de>
+Date: Fri, 22 Nov 2013 14:22:53 +0100
+Subject: [PATCH 33/54] dmaengine: Add support for BCM2708
+
+Add support for DMA controller of BCM2708 as used in the Raspberry Pi.
+Currently it only supports cyclic DMA.
+
+Signed-off-by: Florian Meier <florian.meier@koalo.de>
+---
+ drivers/dma/Kconfig             |   6 +
+ drivers/dma/Makefile            |   1 +
+ drivers/dma/bcm2708-dmaengine.c | 588 ++++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 595 insertions(+)
+ create mode 100644 drivers/dma/bcm2708-dmaengine.c
+
+diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
+index 605b016..edd5842 100644
+--- a/drivers/dma/Kconfig
++++ b/drivers/dma/Kconfig
+@@ -312,6 +312,12 @@ config DMA_BCM2835
+ 	select DMA_ENGINE
+ 	select DMA_VIRTUAL_CHANNELS
+ 
++config DMA_BCM2708
++	tristate "BCM2708 DMA engine support"
++	depends on MACH_BCM2708
++	select DMA_ENGINE
++	select DMA_VIRTUAL_CHANNELS
++
+ config TI_CPPI41
+ 	tristate "AM33xx CPPI41 DMA support"
+ 	depends on ARCH_OMAP
+diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
+index a029d0f4..f4d9516 100644
+--- a/drivers/dma/Makefile
++++ b/drivers/dma/Makefile
+@@ -39,6 +39,7 @@ obj-$(CONFIG_DMA_SA11X0) += sa11x0-dma.o
+ obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o
+ obj-$(CONFIG_DMA_OMAP) += omap-dma.o
+ obj-$(CONFIG_DMA_BCM2835) += bcm2835-dma.o
++obj-$(CONFIG_DMA_BCM2708) += bcm2708-dmaengine.o
+ obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o
+ obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o
+ obj-$(CONFIG_TI_CPPI41) += cppi41.o
+diff --git a/drivers/dma/bcm2708-dmaengine.c b/drivers/dma/bcm2708-dmaengine.c
+new file mode 100644
+index 0000000..b244293
+--- /dev/null
++++ b/drivers/dma/bcm2708-dmaengine.c
+@@ -0,0 +1,588 @@
++/*
++ * BCM2708 DMA engine support
++ *
++ * This driver only supports cyclic DMA transfers
++ * as needed for the I2S module.
++ *
++ * Author:      Florian Meier <florian.meier@koalo.de>
++ *              Copyright 2013
++ *
++ * Based on
++ *	OMAP DMAengine support by Russell King
++ *
++ *	BCM2708 DMA Driver
++ *	Copyright (C) 2010 Broadcom
++ *
++ *	Raspberry Pi PCM I2S ALSA Driver
++ *	Copyright (c) by Phil Poole 2013
++ *
++ *	MARVELL MMP Peripheral DMA Driver
++ *	Copyright 2012 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
++ * (at your option) 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/dmaengine.h>
++#include <linux/dma-mapping.h>
++#include <linux/err.h>
++#include <linux/init.h>
++#include <linux/interrupt.h>
++#include <linux/list.h>
++#include <linux/module.h>
++#include <linux/platform_device.h>
++#include <linux/slab.h>
++#include <linux/io.h>
++#include <linux/spinlock.h>
++#include <linux/irq.h>
++
++#include "virt-dma.h"
++
++#include <mach/dma.h>
++#include <mach/irqs.h>
++
++struct bcm2708_dmadev {
++	struct dma_device ddev;
++	spinlock_t lock;
++	void __iomem *base;
++	struct device_dma_parameters dma_parms;
++};
++
++struct bcm2708_chan {
++	struct virt_dma_chan vc;
++	struct list_head node;
++
++	struct dma_slave_config	cfg;
++	bool cyclic;
++
++	int ch;
++	struct bcm2708_desc *desc;
++
++	void __iomem *chan_base;
++	int irq_number;
++};
++
++struct bcm2708_desc {
++	struct virt_dma_desc vd;
++	enum dma_transfer_direction dir;
++
++	unsigned int control_block_size;
++	struct bcm2708_dma_cb *control_block_base;
++	dma_addr_t control_block_base_phys;
++
++	unsigned frames;
++	size_t size;
++};
++
++#define BCM2708_DMA_DATA_TYPE_S8	1
++#define BCM2708_DMA_DATA_TYPE_S16	2
++#define BCM2708_DMA_DATA_TYPE_S32	4
++#define BCM2708_DMA_DATA_TYPE_S128	16
++
++static inline struct bcm2708_dmadev *to_bcm2708_dma_dev(struct dma_device *d)
++{
++	return container_of(d, struct bcm2708_dmadev, ddev);
++}
++
++static inline struct bcm2708_chan *to_bcm2708_dma_chan(struct dma_chan *c)
++{
++	return container_of(c, struct bcm2708_chan, vc.chan);
++}
++
++static inline struct bcm2708_desc *to_bcm2708_dma_desc(
++		struct dma_async_tx_descriptor *t)
++{
++	return container_of(t, struct bcm2708_desc, vd.tx);
++}
++
++static void bcm2708_dma_desc_free(struct virt_dma_desc *vd)
++{
++	struct bcm2708_desc *desc = container_of(vd, struct bcm2708_desc, vd);
++	dma_free_coherent(desc->vd.tx.chan->device->dev,
++			desc->control_block_size,
++			desc->control_block_base,
++			desc->control_block_base_phys);
++	kfree(desc);
++}
++
++static void bcm2708_dma_start_desc(struct bcm2708_chan *c)
++{
++	struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
++	struct bcm2708_desc *d;
++
++	if (!vd) {
++		c->desc = NULL;
++		return;
++	}
++
++	list_del(&vd->node);
++
++	c->desc = d = to_bcm2708_dma_desc(&vd->tx);
++
++	bcm_dma_start(c->chan_base, d->control_block_base_phys);
++}
++
++static irqreturn_t bcm2708_dma_callback(int irq, void *data)
++{
++	struct bcm2708_chan *c = data;
++	struct bcm2708_desc *d;
++	unsigned long flags;
++
++	spin_lock_irqsave(&c->vc.lock, flags);
++
++	/* Acknowledge interrupt */
++	writel(BCM2708_DMA_INT, c->chan_base + BCM2708_DMA_CS);
++
++	d = c->desc;
++
++	if (d) {
++		/* TODO Only works for cyclic DMA */
++		vchan_cyclic_callback(&d->vd);
++	}
++
++	/* Keep the DMA engine running */
++	dsb(); /* ARM synchronization barrier */
++	writel(BCM2708_DMA_ACTIVE, c->chan_base + BCM2708_DMA_CS);
++
++	spin_unlock_irqrestore(&c->vc.lock, flags);
++
++	return IRQ_HANDLED;
++}
++
++static int bcm2708_dma_alloc_chan_resources(struct dma_chan *chan)
++{
++	struct bcm2708_chan *c = to_bcm2708_dma_chan(chan);
++
++	return request_irq(c->irq_number,
++			bcm2708_dma_callback, 0, "DMA IRQ", c);
++}
++
++static void bcm2708_dma_free_chan_resources(struct dma_chan *chan)
++{
++	struct bcm2708_chan *c = to_bcm2708_dma_chan(chan);
++
++	vchan_free_chan_resources(&c->vc);
++	free_irq(c->irq_number, c);
++
++	dev_dbg(c->vc.chan.device->dev, "Freeing DMA channel %u\n", c->ch);
++}
++
++static size_t bcm2708_dma_desc_size(struct bcm2708_desc *d)
++{
++	return d->size;
++}
++
++static size_t bcm2708_dma_desc_size_pos(struct bcm2708_desc *d, dma_addr_t addr)
++{
++	unsigned i;
++	size_t size;
++
++	for (size = i = 0; i < d->frames; i++) {
++		struct bcm2708_dma_cb *control_block =
++			&d->control_block_base[i];
++		size_t this_size = control_block->length;
++		dma_addr_t dma;
++
++		if (d->dir == DMA_DEV_TO_MEM)
++			dma = control_block->dst;
++		else
++			dma = control_block->src;
++
++		if (size)
++			size += this_size;
++		else if (addr >= dma && addr < dma + this_size)
++			size += dma + this_size - addr;
++	}
++
++	return size;
++}
++
++static enum dma_status bcm2708_dma_tx_status(struct dma_chan *chan,
++	dma_cookie_t cookie, struct dma_tx_state *txstate)
++{
++	struct bcm2708_chan *c = to_bcm2708_dma_chan(chan);
++	struct virt_dma_desc *vd;
++	enum dma_status ret;
++	unsigned long flags;
++
++	ret = dma_cookie_status(chan, cookie, txstate);
++	if (ret == DMA_COMPLETE || !txstate)
++		return ret;
++
++	spin_lock_irqsave(&c->vc.lock, flags);
++	vd = vchan_find_desc(&c->vc, cookie);
++	if (vd) {
++		txstate->residue =
++			bcm2708_dma_desc_size(to_bcm2708_dma_desc(&vd->tx));
++	} else if (c->desc && c->desc->vd.tx.cookie == cookie) {
++		struct bcm2708_desc *d = c->desc;
++		dma_addr_t pos;
++
++		if (d->dir == DMA_MEM_TO_DEV)
++			pos = readl(c->chan_base + BCM2708_DMA_SOURCE_AD);
++		else if (d->dir == DMA_DEV_TO_MEM)
++			pos = readl(c->chan_base + BCM2708_DMA_DEST_AD);
++		else
++			pos = 0;
++
++		txstate->residue = bcm2708_dma_desc_size_pos(d, pos);
++	} else {
++		txstate->residue = 0;
++	}
++
++	spin_unlock_irqrestore(&c->vc.lock, flags);
++
++	return ret;
++}
++
++static void bcm2708_dma_issue_pending(struct dma_chan *chan)
++{
++	struct bcm2708_chan *c = to_bcm2708_dma_chan(chan);
++	unsigned long flags;
++
++	c->cyclic = true; /* Nothing else is implemented */
++
++	spin_lock_irqsave(&c->vc.lock, flags);
++	if (vchan_issue_pending(&c->vc) && !c->desc)
++		bcm2708_dma_start_desc(c);
++
++	spin_unlock_irqrestore(&c->vc.lock, flags);
++}
++
++static struct dma_async_tx_descriptor *bcm2708_dma_prep_dma_cyclic(
++	struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
++	size_t period_len, enum dma_transfer_direction direction,
++	unsigned long flags, void *context)
++{
++	struct bcm2708_chan *c = to_bcm2708_dma_chan(chan);
++	enum dma_slave_buswidth dev_width;
++	struct bcm2708_desc *d;
++	dma_addr_t dev_addr;
++	unsigned es, sync_type;
++	unsigned frame;
++
++	/* Grab configuration */
++	if (direction == DMA_DEV_TO_MEM) {
++		dev_addr = c->cfg.src_addr;
++		dev_width = c->cfg.src_addr_width;
++		sync_type = BCM2708_DMA_S_DREQ;
++	} else if (direction == DMA_MEM_TO_DEV) {
++		dev_addr = c->cfg.dst_addr;
++		dev_width = c->cfg.dst_addr_width;
++		sync_type = BCM2708_DMA_D_DREQ;
++	} else {
++		dev_err(chan->device->dev, "%s: bad direction?\n", __func__);
++		return NULL;
++	}
++
++	/* Bus width translates to the element size (ES) */
++	switch (dev_width) {
++	case DMA_SLAVE_BUSWIDTH_4_BYTES:
++		es = BCM2708_DMA_DATA_TYPE_S32;
++		break;
++	default:
++		return NULL;
++	}
++
++	/* Now allocate and setup the descriptor. */
++	d = kzalloc(sizeof(*d), GFP_NOWAIT);
++	if (!d)
++		return NULL;
++
++	d->dir = direction;
++	d->frames = buf_len / period_len;
++
++	/* Allocate memory for control blocks */
++	d->control_block_size = d->frames * sizeof(struct bcm2708_dma_cb);
++	d->control_block_base = dma_zalloc_coherent(chan->device->dev,
++			d->control_block_size, &d->control_block_base_phys,
++			GFP_NOWAIT);
++
++	if (!d->control_block_base) {
++		kfree(d);
++		return NULL;
++	}
++
++	/*
++	 * Iterate over all frames, create a control block
++	 * for each frame and link them together.
++	 */
++	for (frame = 0; frame < d->frames; frame++) {
++		struct bcm2708_dma_cb *control_block =
++			&d->control_block_base[frame];
++
++		/* Setup adresses */
++		if (d->dir == DMA_DEV_TO_MEM) {
++			control_block->info = BCM2708_DMA_D_INC;
++			control_block->src = dev_addr;
++			control_block->dst = buf_addr + frame * period_len;
++		} else {
++			control_block->info = BCM2708_DMA_S_INC;
++			control_block->src = buf_addr + frame * period_len;
++			control_block->dst = dev_addr;
++		}
++
++		/* Enable interrupt */
++		control_block->info |= BCM2708_DMA_INT_EN;
++
++		/* Setup synchronization */
++		if (sync_type != 0)
++			control_block->info |= sync_type;
++
++		/* Setup DREQ channel */
++		if (c->cfg.slave_id != 0)
++			control_block->info |=
++				BCM2708_DMA_PER_MAP(c->cfg.slave_id);
++
++		/* Length of a frame */
++		control_block->length = period_len;
++		d->size += control_block->length;
++
++		/*
++		 * Next block is the next frame.
++		 * This DMA engine driver currently only supports cyclic DMA.
++		 * Therefore, wrap around at number of frames.
++		 */
++		control_block->next = d->control_block_base_phys +
++			sizeof(struct bcm2708_dma_cb)
++			* ((frame + 1) % d->frames);
++	}
++
++	return vchan_tx_prep(&c->vc, &d->vd, flags);
++}
++
++static int bcm2708_dma_slave_config(struct bcm2708_chan *c,
++		struct dma_slave_config *cfg)
++{
++	if ((cfg->direction == DMA_DEV_TO_MEM &&
++	     cfg->src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) ||
++	    (cfg->direction == DMA_MEM_TO_DEV &&
++	     cfg->dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) ||
++	    !is_slave_direction(cfg->direction)) {
++		return -EINVAL;
++	}
++
++	c->cfg = *cfg;
++
++	return 0;
++}
++
++static int bcm2708_dma_terminate_all(struct bcm2708_chan *c)
++{
++	struct bcm2708_dmadev *d = to_bcm2708_dma_dev(c->vc.chan.device);
++	unsigned long flags;
++	int timeout = 10000;
++	LIST_HEAD(head);
++
++	spin_lock_irqsave(&c->vc.lock, flags);
++
++	/* Prevent this channel being scheduled */
++	spin_lock(&d->lock);
++	list_del_init(&c->node);
++	spin_unlock(&d->lock);
++
++	/*
++	 * Stop DMA activity: we assume the callback will not be called
++	 * after bcm_dma_abort() returns (even if it does, it will see
++	 * c->desc is NULL and exit.)
++	 */
++	if (c->desc) {
++		c->desc = NULL;
++		bcm_dma_abort(c->chan_base);
++
++		/* Wait for stopping */
++		while (timeout > 0) {
++			timeout--;
++			if (!(readl(c->chan_base + BCM2708_DMA_CS) &
++						BCM2708_DMA_ACTIVE))
++				break;
++
++			cpu_relax();
++		}
++
++		if (timeout <= 0)
++			dev_err(d->ddev.dev, "DMA transfer could not be terminated\n");
++	}
++
++	vchan_get_all_descriptors(&c->vc, &head);
++	spin_unlock_irqrestore(&c->vc.lock, flags);
++	vchan_dma_desc_free_list(&c->vc, &head);
++
++	return 0;
++}
++
++static int bcm2708_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
++	unsigned long arg)
++{
++	struct bcm2708_chan *c = to_bcm2708_dma_chan(chan);
++
++	switch (cmd) {
++	case DMA_SLAVE_CONFIG:
++		return bcm2708_dma_slave_config(c,
++				(struct dma_slave_config *)arg);
++
++	case DMA_TERMINATE_ALL:
++		return bcm2708_dma_terminate_all(c);
++
++	default:
++		return -ENXIO;
++	}
++}
++
++static int bcm2708_dma_chan_init(struct bcm2708_dmadev *d, void __iomem* chan_base,
++									int chan_id, int irq)
++{
++	struct bcm2708_chan *c;
++
++	c = devm_kzalloc(d->ddev.dev, sizeof(*c), GFP_KERNEL);
++	if (!c)
++		return -ENOMEM;
++
++	c->vc.desc_free = bcm2708_dma_desc_free;
++	vchan_init(&c->vc, &d->ddev);
++	INIT_LIST_HEAD(&c->node);
++
++	d->ddev.chancnt++;
++
++	c->chan_base = chan_base;
++	c->ch = chan_id;
++	c->irq_number = irq;
++
++	return 0;
++}
++
++static void bcm2708_dma_free(struct bcm2708_dmadev *od)
++{
++	while (!list_empty(&od->ddev.channels)) {
++		struct bcm2708_chan *c = list_first_entry(&od->ddev.channels,
++			struct bcm2708_chan, vc.chan.device_node);
++
++		list_del(&c->vc.chan.device_node);
++		tasklet_kill(&c->vc.task);
++	}
++}
++
++static int bcm2708_dma_probe(struct platform_device *pdev)
++{
++	struct bcm2708_dmadev *od;
++	int rc, i;
++
++	if (!pdev->dev.dma_mask)
++		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
++
++	rc = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
++	if (rc)
++		return rc;
++	dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
++
++	od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
++	if (!od)
++		return -ENOMEM;
++
++	pdev->dev.dma_parms = &od->dma_parms;
++	dma_set_max_seg_size(&pdev->dev, 0x3FFFFFFF);
++
++	dma_cap_set(DMA_SLAVE, od->ddev.cap_mask);
++	dma_cap_set(DMA_CYCLIC, od->ddev.cap_mask);
++	od->ddev.device_alloc_chan_resources = bcm2708_dma_alloc_chan_resources;
++	od->ddev.device_free_chan_resources = bcm2708_dma_free_chan_resources;
++	od->ddev.device_tx_status = bcm2708_dma_tx_status;
++	od->ddev.device_issue_pending = bcm2708_dma_issue_pending;
++	od->ddev.device_prep_dma_cyclic = bcm2708_dma_prep_dma_cyclic;
++	od->ddev.device_control = bcm2708_dma_control;
++	od->ddev.dev = &pdev->dev;
++	INIT_LIST_HEAD(&od->ddev.channels);
++	spin_lock_init(&od->lock);
++
++	platform_set_drvdata(pdev, od);
++
++	for (i = 0; i < 16; i++) {
++		void __iomem* chan_base;
++		int chan_id, irq;
++
++		chan_id = bcm_dma_chan_alloc(BCM_DMA_FEATURE_FAST,
++			&chan_base,
++			&irq);
++
++		if (chan_id < 0)
++			break;
++
++		rc = bcm2708_dma_chan_init(od, chan_base, chan_id, irq);
++		if (rc) {
++			bcm2708_dma_free(od);
++			return rc;
++		}
++	}
++
++	rc = dma_async_device_register(&od->ddev);
++	if (rc) {
++		dev_err(&pdev->dev,
++			"Failed to register slave DMA engine device: %d\n", rc);
++		bcm2708_dma_free(od);
++		return rc;
++	}
++
++	dev_dbg(&pdev->dev, "Load BCM2708 DMA engine driver\n");
++
++	return rc;
++}
++
++static int bcm2708_dma_remove(struct platform_device *pdev)
++{
++	struct bcm2708_dmadev *od = platform_get_drvdata(pdev);
++
++	dma_async_device_unregister(&od->ddev);
++	bcm2708_dma_free(od);
++
++	return 0;
++}
++
++static struct platform_driver bcm2708_dma_driver = {
++	.probe	= bcm2708_dma_probe,
++	.remove	= bcm2708_dma_remove,
++	.driver = {
++		.name = "bcm2708-dmaengine",
++		.owner = THIS_MODULE,
++	},
++};
++
++static struct platform_device *pdev;
++
++static const struct platform_device_info bcm2708_dma_dev_info = {
++	.name = "bcm2708-dmaengine",
++	.id = -1,
++};
++
++static int bcm2708_dma_init(void)
++{
++	int rc = platform_driver_register(&bcm2708_dma_driver);
++
++	if (rc == 0) {
++		pdev = platform_device_register_full(&bcm2708_dma_dev_info);
++		if (IS_ERR(pdev)) {
++			platform_driver_unregister(&bcm2708_dma_driver);
++			rc = PTR_ERR(pdev);
++		}
++	}
++
++	return rc;
++}
++subsys_initcall(bcm2708_dma_init);
++
++static void __exit bcm2708_dma_exit(void)
++{
++	platform_device_unregister(pdev);
++	platform_driver_unregister(&bcm2708_dma_driver);
++}
++module_exit(bcm2708_dma_exit);
++
++MODULE_ALIAS("platform:bcm2708-dma");
++MODULE_DESCRIPTION("BCM2708 DMA engine driver");
++MODULE_AUTHOR("Florian Meier <florian.meier@koalo.de>");
++MODULE_LICENSE("GPL v2");
+-- 
+1.9.1
+