diff options
Diffstat (limited to 'target/linux/brcm2708/patches-3.10/0114-dmaengine-Add-support-for-BCM2708.patch')
-rw-r--r-- | target/linux/brcm2708/patches-3.10/0114-dmaengine-Add-support-for-BCM2708.patch | 630 |
1 files changed, 630 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-3.10/0114-dmaengine-Add-support-for-BCM2708.patch b/target/linux/brcm2708/patches-3.10/0114-dmaengine-Add-support-for-BCM2708.patch new file mode 100644 index 0000000000..e1829208aa --- /dev/null +++ b/target/linux/brcm2708/patches-3.10/0114-dmaengine-Add-support-for-BCM2708.patch @@ -0,0 +1,630 @@ +From 5fa4eb7d17acff35c1ea9a7def5dec5802566565 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 114/174] 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 + +--- a/drivers/dma/Kconfig ++++ b/drivers/dma/Kconfig +@@ -305,6 +305,12 @@ config DMA_OMAP + 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 MMP_PDMA + bool "MMP PDMA support" + depends on (ARCH_MMP || ARCH_PXA) +--- a/drivers/dma/Makefile ++++ b/drivers/dma/Makefile +@@ -37,4 +37,5 @@ obj-$(CONFIG_EP93XX_DMA) += ep93xx_dma.o + obj-$(CONFIG_DMA_SA11X0) += sa11x0-dma.o + obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o + obj-$(CONFIG_DMA_OMAP) += omap-dma.o ++obj-$(CONFIG_DMA_BCM2708) += bcm2708-dmaengine.o + obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o +--- /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_SUCCESS || !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"); |