From: Peter De Schrijver <pdeschrijver@xxxxxxxxxx> The Tegra20 fuse driver is the only user of tegra_apb_readl_using_dma(). Therefore we can simply the code by incorporating the APB DMA handling into the driver directly. tegra_apb_writel_using_dma() is dropped because there are no users. Signed-off-by: Peter De Schrijver <pdeschrijver@xxxxxxxxxx> Signed-off-by: Stephen Warren <swarren@xxxxxxxxxx> Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> --- arch/arm/mach-tegra/Makefile | 1 - arch/arm/mach-tegra/apbio.c | 217 ---------------------------------- arch/arm/mach-tegra/apbio.h | 22 ---- arch/arm/mach-tegra/tegra.c | 2 - drivers/soc/tegra/fuse/fuse-tegra20.c | 79 ++++++++++++- include/linux/tegra-soc.h | 14 --- 6 files changed, 76 insertions(+), 259 deletions(-) delete mode 100644 arch/arm/mach-tegra/apbio.c delete mode 100644 arch/arm/mach-tegra/apbio.h diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile index e8601bb56f98..c303b55de22e 100644 --- a/arch/arm/mach-tegra/Makefile +++ b/arch/arm/mach-tegra/Makefile @@ -5,7 +5,6 @@ obj-y += irq.o obj-y += pmc.o obj-y += flowctrl.o obj-y += powergate.o -obj-y += apbio.o obj-y += pm.o obj-y += reset.o obj-y += reset-handler.o 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); -} diff --git a/arch/arm/mach-tegra/apbio.h b/arch/arm/mach-tegra/apbio.h deleted file mode 100644 index f05d71c303c7..000000000000 --- a/arch/arm/mach-tegra/apbio.h +++ /dev/null @@ -1,22 +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. - * - */ - -#ifndef __MACH_TEGRA_APBIO_H -#define __MACH_TEGRA_APBIO_H - -void tegra_apb_io_init(void); -u32 tegra_apb_readl(unsigned long offset); -void tegra_apb_writel(u32 value, unsigned long offset); -#endif diff --git a/arch/arm/mach-tegra/tegra.c b/arch/arm/mach-tegra/tegra.c index 1d60be4975b8..869fddd7e83e 100644 --- a/arch/arm/mach-tegra/tegra.c +++ b/arch/arm/mach-tegra/tegra.c @@ -43,7 +43,6 @@ #include <asm/setup.h> #include <asm/trusted_foundations.h> -#include "apbio.h" #include "board.h" #include "common.h" #include "cpuidle.h" @@ -73,7 +72,6 @@ u32 tegra_uart_config[3] = { static void __init tegra_init_early(void) { of_register_trusted_foundations(); - tegra_apb_io_init(); tegra_init_fuse(); tegra_cpu_reset_handler_init(); tegra_powergate_init(); diff --git a/drivers/soc/tegra/fuse/fuse-tegra20.c b/drivers/soc/tegra/fuse/fuse-tegra20.c index 09f91bf8c743..c3dcf1118337 100644 --- a/drivers/soc/tegra/fuse/fuse-tegra20.c +++ b/drivers/soc/tegra/fuse/fuse-tegra20.c @@ -18,6 +18,9 @@ #include <linux/device.h> #include <linux/clk.h> +#include <linux/completion.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/io.h> #include <linux/kernel.h> @@ -38,18 +41,58 @@ static phys_addr_t fuse_phys; static struct clk *fuse_clk; static void __iomem __initdata *fuse_base; +static DEFINE_MUTEX(apb_dma_lock); +static DECLARE_COMPLETION(apb_dma_wait); +static struct dma_chan *apb_dma_chan; +static struct dma_slave_config dma_sconfig; +static u32 *apb_buffer; +static dma_addr_t apb_buffer_phys; + +static void apb_dma_complete(void *args) +{ + complete(&apb_dma_wait); +} + static u32 tegra20_fuse_readl(const unsigned int offset) { int ret; - u32 val; + u32 val = 0; + struct dma_async_tx_descriptor *dma_desc; + + mutex_lock(&apb_dma_lock); + + dma_sconfig.src_addr = fuse_phys + FUSE_BEGIN + offset; + ret = dmaengine_slave_config(apb_dma_chan, &dma_sconfig); + if (ret) + goto out; + + dma_desc = dmaengine_prep_slave_single(apb_dma_chan, apb_buffer_phys, + sizeof(u32), DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!dma_desc) + goto out; + + dma_desc->callback = apb_dma_complete; + dma_desc->callback_param = NULL; + + reinit_completion(&apb_dma_wait); clk_prepare_enable(fuse_clk); - ret = tegra_apb_readl_using_dma(fuse_phys + FUSE_BEGIN + offset, &val); + dmaengine_submit(dma_desc); + dma_async_issue_pending(apb_dma_chan); + ret = wait_for_completion_timeout(&apb_dma_wait, msecs_to_jiffies(50)); + + if (WARN(ret == 0, "apb read dma timed out")) + dmaengine_terminate_all(apb_dma_chan); + else + val = *apb_buffer; clk_disable_unprepare(fuse_clk); +out: + mutex_unlock(&apb_dma_lock); - return (ret < 0) ? 0 : val; + return val; } static const struct of_device_id tegra20_fuse_of_match[] = { @@ -57,9 +100,35 @@ static const struct of_device_id tegra20_fuse_of_match[] = { {}, }; +static int apb_dma_init(void) +{ + dma_cap_mask_t mask; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + apb_dma_chan = dma_request_channel(mask, NULL, NULL); + if (!apb_dma_chan) + return -EPROBE_DEFER; + + apb_buffer = dma_alloc_coherent(NULL, sizeof(u32), &apb_buffer_phys, + GFP_KERNEL); + if (!apb_buffer) { + dma_release_channel(apb_dma_chan); + return -ENOMEM; + } + + 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; + + return 0; +} + static int tegra20_fuse_probe(struct platform_device *pdev) { struct resource *res; + int err; fuse_clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(fuse_clk)) { @@ -72,6 +141,10 @@ static int tegra20_fuse_probe(struct platform_device *pdev) return -EINVAL; fuse_phys = res->start; + err = apb_dma_init(); + if (err) + return err; + if (tegra_fuse_create_sysfs(&pdev->dev, FUSE_SIZE, tegra20_fuse_readl)) return -ENODEV; diff --git a/include/linux/tegra-soc.h b/include/linux/tegra-soc.h index 3d984219aaa1..7e8a33a88545 100644 --- a/include/linux/tegra-soc.h +++ b/include/linux/tegra-soc.h @@ -61,20 +61,6 @@ int tegra_fuse_readl(unsigned long offset, u32 *value); extern struct tegra_sku_info tegra_sku_info; -#if defined(CONFIG_TEGRA20_APB_DMA) -int tegra_apb_readl_using_dma(unsigned long offset, u32 *value); -int tegra_apb_writel_using_dma(u32 value, unsigned long offset); -#else -static inline int tegra_apb_readl_using_dma(unsigned long offset, u32 *value) -{ - return -EINVAL; -} -static inline int tegra_apb_writel_using_dma(u32 value, unsigned long offset) -{ - return -EINVAL; -} -#endif /* CONFIG_TEGRA20_APB_DMA */ - #endif /* __ASSEMBLY__ */ #endif /* __LINUX_TEGRA_SOC_H_ */ -- 2.0.1 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html