diff options
Diffstat (limited to 'arch/arm/mach-tegra/apbio.c')
| -rw-r--r-- | arch/arm/mach-tegra/apbio.c | 217 |
1 files changed, 0 insertions, 217 deletions
diff --git a/arch/arm/mach-tegra/apbio.c b/arch/arm/mach-tegra/apbio.c deleted file mode 100644 index f2488722c79c..000000000000 --- a/arch/arm/mach-tegra/apbio.c +++ /dev/null @@ -1,217 +0,0 @@ -/* - * Copyright (C) 2010 NVIDIA Corporation. - * Copyright (C) 2010 Google, Inc. - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * 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/completion.h> -#include <linux/dmaengine.h> -#include <linux/dma-mapping.h> -#include <linux/io.h> -#include <linux/kernel.h> -#include <linux/mutex.h> -#include <linux/of.h> -#include <linux/sched.h> -#include <linux/spinlock.h> - -#include "apbio.h" -#include "iomap.h" - -#if defined(CONFIG_TEGRA20_APB_DMA) -static DEFINE_MUTEX(tegra_apb_dma_lock); -static u32 *tegra_apb_bb; -static dma_addr_t tegra_apb_bb_phys; -static DECLARE_COMPLETION(tegra_apb_wait); - -static int tegra_apb_readl_direct(unsigned long offset, u32 *value); -static int tegra_apb_writel_direct(u32 value, unsigned long offset); - -static struct dma_chan *tegra_apb_dma_chan; -static struct dma_slave_config dma_sconfig; - -static bool tegra_apb_dma_init(void) -{ - dma_cap_mask_t mask; - - mutex_lock(&tegra_apb_dma_lock); - - /* Check to see if we raced to setup */ - if (tegra_apb_dma_chan) - goto skip_init; - - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - tegra_apb_dma_chan = dma_request_channel(mask, NULL, NULL); - if (!tegra_apb_dma_chan) { - /* - * This is common until the device is probed, so don't - * shout about it. - */ - pr_debug("%s: can not allocate dma channel\n", __func__); - goto err_dma_alloc; - } - - tegra_apb_bb = dma_alloc_coherent(NULL, sizeof(u32), - &tegra_apb_bb_phys, GFP_KERNEL); - if (!tegra_apb_bb) { - pr_err("%s: can not allocate bounce buffer\n", __func__); - goto err_buff_alloc; - } - - dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - dma_sconfig.src_maxburst = 1; - dma_sconfig.dst_maxburst = 1; - -skip_init: - mutex_unlock(&tegra_apb_dma_lock); - return true; - -err_buff_alloc: - dma_release_channel(tegra_apb_dma_chan); - tegra_apb_dma_chan = NULL; - -err_dma_alloc: - mutex_unlock(&tegra_apb_dma_lock); - return false; -} - -static void apb_dma_complete(void *args) -{ - complete(&tegra_apb_wait); -} - -static int do_dma_transfer(unsigned long apb_add, - enum dma_transfer_direction dir) -{ - struct dma_async_tx_descriptor *dma_desc; - int ret; - - if (dir == DMA_DEV_TO_MEM) - dma_sconfig.src_addr = apb_add; - else - dma_sconfig.dst_addr = apb_add; - - ret = dmaengine_slave_config(tegra_apb_dma_chan, &dma_sconfig); - if (ret) - return ret; - - dma_desc = dmaengine_prep_slave_single(tegra_apb_dma_chan, - tegra_apb_bb_phys, sizeof(u32), dir, - DMA_PREP_INTERRUPT | DMA_CTRL_ACK); - if (!dma_desc) - return -EINVAL; - - dma_desc->callback = apb_dma_complete; - dma_desc->callback_param = NULL; - - reinit_completion(&tegra_apb_wait); - - dmaengine_submit(dma_desc); - dma_async_issue_pending(tegra_apb_dma_chan); - ret = wait_for_completion_timeout(&tegra_apb_wait, - msecs_to_jiffies(50)); - - if (WARN(ret == 0, "apb read dma timed out")) { - dmaengine_terminate_all(tegra_apb_dma_chan); - return -EFAULT; - } - return 0; -} - -int tegra_apb_readl_using_dma(unsigned long offset, u32 *value) -{ - int ret; - - if (!tegra_apb_dma_chan && !tegra_apb_dma_init()) - return tegra_apb_readl_direct(offset, value); - - mutex_lock(&tegra_apb_dma_lock); - ret = do_dma_transfer(offset, DMA_DEV_TO_MEM); - if (ret < 0) - pr_err("error in reading offset 0x%08lx using dma\n", offset); - else - *value = *tegra_apb_bb; - - mutex_unlock(&tegra_apb_dma_lock); - - return ret; -} - -int tegra_apb_writel_using_dma(u32 value, unsigned long offset) -{ - int ret; - - if (!tegra_apb_dma_chan && !tegra_apb_dma_init()) - return tegra_apb_writel_direct(value, offset); - - mutex_lock(&tegra_apb_dma_lock); - *((u32 *)tegra_apb_bb) = value; - ret = do_dma_transfer(offset, DMA_MEM_TO_DEV); - mutex_unlock(&tegra_apb_dma_lock); - if (ret < 0) - pr_err("error in writing offset 0x%08lx using dma\n", offset); - - return ret; -} -#else -#define tegra_apb_readl_using_dma tegra_apb_readl_direct -#define tegra_apb_writel_using_dma tegra_apb_writel_direct -#endif - -typedef int (*apbio_read_fptr)(unsigned long offset, u32 *value); -typedef int (*apbio_write_fptr)(u32 value, unsigned long offset); - -static apbio_read_fptr apbio_read; -static apbio_write_fptr apbio_write; - -static int tegra_apb_readl_direct(unsigned long offset, u32 *value) -{ - *value = readl(IO_ADDRESS(offset)); - - return 0; -} - -static int tegra_apb_writel_direct(u32 value, unsigned long offset) -{ - writel(value, IO_ADDRESS(offset)); - - return 0; -} - -void tegra_apb_io_init(void) -{ - /* Need to use dma only when it is Tegra20 based platform */ - if (of_machine_is_compatible("nvidia,tegra20") || - !of_have_populated_dt()) { - apbio_read = tegra_apb_readl_using_dma; - apbio_write = tegra_apb_writel_using_dma; - } else { - apbio_read = tegra_apb_readl_direct; - apbio_write = tegra_apb_writel_direct; - } -} - -u32 tegra_apb_readl(unsigned long offset) -{ - u32 val; - - if (apbio_read(offset, &val) < 0) - return 0; - else - return val; -} - -void tegra_apb_writel(u32 value, unsigned long offset) -{ - apbio_write(value, offset); -} |