diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile index e120ff54f663..23d15fba3843 100644 --- a/arch/arm/mach-tegra/Makefile +++ b/arch/arm/mach-tegra/Makefile @@ -15,7 +15,7 @@ obj-$(CONFIG_ARCH_TEGRA_3x_SOC) += pinmux-tegra30-tables.o obj-$(CONFIG_ARCH_TEGRA_3x_SOC) += board-dt-tegra30.o obj-$(CONFIG_SMP) += platsmp.o localtimer.o headsmp.o obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o -obj-$(CONFIG_TEGRA_SYSTEM_DMA) += dma.o +obj-$(CONFIG_TEGRA_SYSTEM_DMA) += dma.o apbio.o obj-$(CONFIG_CPU_FREQ) += cpu-tegra.o obj-$(CONFIG_TEGRA_PCI) += pcie.o obj-$(CONFIG_USB_SUPPORT) += usb_phy.o diff --git a/arch/arm/mach-tegra/apbio.c b/arch/arm/mach-tegra/apbio.c new file mode 100644 index 000000000000..e75451e517bd --- /dev/null +++ b/arch/arm/mach-tegra/apbio.c @@ -0,0 +1,145 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "apbio.h" + +static DEFINE_MUTEX(tegra_apb_dma_lock); + +static struct tegra_dma_channel *tegra_apb_dma; +static u32 *tegra_apb_bb; +static dma_addr_t tegra_apb_bb_phys; +static DECLARE_COMPLETION(tegra_apb_wait); + +bool tegra_apb_init(void) +{ + struct tegra_dma_channel *ch; + + mutex_lock(&tegra_apb_dma_lock); + + /* Check to see if we raced to setup */ + if (tegra_apb_dma) + goto out; + + ch = tegra_dma_allocate_channel(TEGRA_DMA_MODE_ONESHOT | + TEGRA_DMA_SHARED); + + if (!ch) + goto out_fail; + + 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__); + tegra_dma_free_channel(ch); + goto out_fail; + } + + tegra_apb_dma = ch; +out: + mutex_unlock(&tegra_apb_dma_lock); + return true; + +out_fail: + mutex_unlock(&tegra_apb_dma_lock); + return false; +} + +static void apb_dma_complete(struct tegra_dma_req *req) +{ + complete(&tegra_apb_wait); +} + +u32 tegra_apb_readl(unsigned long offset) +{ + struct tegra_dma_req req; + int ret; + + if (!tegra_apb_dma && !tegra_apb_init()) + return readl(IO_TO_VIRT(offset)); + + mutex_lock(&tegra_apb_dma_lock); + req.complete = apb_dma_complete; + req.to_memory = 1; + req.dest_addr = tegra_apb_bb_phys; + req.dest_bus_width = 32; + req.dest_wrap = 1; + req.source_addr = offset; + req.source_bus_width = 32; + req.source_wrap = 4; + req.req_sel = TEGRA_DMA_REQ_SEL_CNTR; + req.size = 4; + + INIT_COMPLETION(tegra_apb_wait); + + tegra_dma_enqueue_req(tegra_apb_dma, &req); + + ret = wait_for_completion_timeout(&tegra_apb_wait, + msecs_to_jiffies(50)); + + if (WARN(ret == 0, "apb read dma timed out")) { + tegra_dma_dequeue_req(tegra_apb_dma, &req); + *(u32 *)tegra_apb_bb = 0; + } + + mutex_unlock(&tegra_apb_dma_lock); + return *((u32 *)tegra_apb_bb); +} + +void tegra_apb_writel(u32 value, unsigned long offset) +{ + struct tegra_dma_req req; + int ret; + + if (!tegra_apb_dma && !tegra_apb_init()) { + writel(value, IO_TO_VIRT(offset)); + return; + } + + mutex_lock(&tegra_apb_dma_lock); + *((u32 *)tegra_apb_bb) = value; + req.complete = apb_dma_complete; + req.to_memory = 0; + req.dest_addr = offset; + req.dest_wrap = 4; + req.dest_bus_width = 32; + req.source_addr = tegra_apb_bb_phys; + req.source_bus_width = 32; + req.source_wrap = 1; + req.req_sel = TEGRA_DMA_REQ_SEL_CNTR; + req.size = 4; + + INIT_COMPLETION(tegra_apb_wait); + + tegra_dma_enqueue_req(tegra_apb_dma, &req); + + ret = wait_for_completion_timeout(&tegra_apb_wait, + msecs_to_jiffies(50)); + + if (WARN(ret == 0, "apb write dma timed out")) + tegra_dma_dequeue_req(tegra_apb_dma, &req); + + mutex_unlock(&tegra_apb_dma_lock); +} diff --git a/arch/arm/mach-tegra/apbio.h b/arch/arm/mach-tegra/apbio.h new file mode 100644 index 000000000000..8b49e8c89a64 --- /dev/null +++ b/arch/arm/mach-tegra/apbio.h @@ -0,0 +1,39 @@ +/* + * 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 + +#ifdef CONFIG_TEGRA_SYSTEM_DMA + +u32 tegra_apb_readl(unsigned long offset); +void tegra_apb_writel(u32 value, unsigned long offset); + +#else +#include +#include + +static inline u32 tegra_apb_readl(unsigned long offset) +{ + return readl(IO_TO_VIRT(offset)); +} + +static inline void tegra_apb_writel(u32 value, unsigned long offset) +{ + writel(value, IO_TO_VIRT(offset)); +} +#endif + +#endif diff --git a/arch/arm/mach-tegra/dma.c b/arch/arm/mach-tegra/dma.c index 98b33c89b2c5..122e46770d93 100644 --- a/arch/arm/mach-tegra/dma.c +++ b/arch/arm/mach-tegra/dma.c @@ -33,6 +33,8 @@ #include #include +#include "apbio.h" + #define APB_DMA_GEN 0x000 #define GEN_ENABLE (1<<31)