diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/mach-tegra/Kconfig | 7 | ||||
| -rw-r--r-- | arch/arm/mach-tegra/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm/mach-tegra/common.c | 7 | ||||
| -rw-r--r-- | arch/arm/mach-tegra/dma.c | 752 | ||||
| -rw-r--r-- | arch/arm/mach-tegra/include/mach/dma.h | 155 |
5 files changed, 922 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig index a57713c1954a..8e32d9d7ec8d 100644 --- a/arch/arm/mach-tegra/Kconfig +++ b/arch/arm/mach-tegra/Kconfig @@ -47,4 +47,11 @@ config TEGRA_DEBUG_UARTE endchoice +config TEGRA_SYSTEM_DMA + bool "Enable system DMA driver for NVIDIA Tegra SoCs" + default y + help + Adds system DMA functionality for NVIDIA Tegra SoCs, used by + several Tegra device drivers + endif diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile index 2a3762179ccf..fc069a9e0f6b 100644 --- a/arch/arm/mach-tegra/Makefile +++ b/arch/arm/mach-tegra/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra2_dvfs.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += pinmux-t2-tables.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_CPU_FREQ) += cpu-tegra.o obj-${CONFIG_MACH_HARMONY} += board-harmony.o diff --git a/arch/arm/mach-tegra/common.c b/arch/arm/mach-tegra/common.c index 445104a993ba..7c91e2b9d643 100644 --- a/arch/arm/mach-tegra/common.c +++ b/arch/arm/mach-tegra/common.c @@ -19,10 +19,13 @@ #include <linux/init.h> #include <linux/io.h> +#include <linux/clk.h> +#include <linux/delay.h> #include <asm/hardware/cache-l2x0.h> #include <mach/iomap.h> +#include <mach/dma.h> #include "board.h" #include "clock.h" @@ -52,6 +55,7 @@ void __init tegra_init_cache(void) l2x0_init(p, 0x6C080001, 0x8200c3fe); #endif + } void __init tegra_common_init(void) @@ -60,4 +64,7 @@ void __init tegra_common_init(void) tegra_init_clock(); tegra_clk_init_from_table(common_clk_init_table); tegra_init_cache(); +#ifdef CONFIG_TEGRA_SYSTEM_DMA + tegra_dma_init(); +#endif } diff --git a/arch/arm/mach-tegra/dma.c b/arch/arm/mach-tegra/dma.c new file mode 100644 index 000000000000..edda6ec5e925 --- /dev/null +++ b/arch/arm/mach-tegra/dma.c @@ -0,0 +1,752 @@ +/* + * arch/arm/mach-tegra/dma.c + * + * System DMA driver for NVIDIA Tegra SoCs + * + * Copyright (c) 2008-2009, NVIDIA Corporation. + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#include <linux/io.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/err.h> +#include <linux/irq.h> +#include <linux/delay.h> +#include <mach/dma.h> +#include <mach/irqs.h> +#include <mach/iomap.h> + +#define APB_DMA_GEN 0x000 +#define GEN_ENABLE (1<<31) + +#define APB_DMA_CNTRL 0x010 + +#define APB_DMA_IRQ_MASK 0x01c + +#define APB_DMA_IRQ_MASK_SET 0x020 + +#define APB_DMA_CHAN_CSR 0x000 +#define CSR_ENB (1<<31) +#define CSR_IE_EOC (1<<30) +#define CSR_HOLD (1<<29) +#define CSR_DIR (1<<28) +#define CSR_ONCE (1<<27) +#define CSR_FLOW (1<<21) +#define CSR_REQ_SEL_SHIFT 16 +#define CSR_REQ_SEL_MASK (0x1F<<CSR_REQ_SEL_SHIFT) +#define CSR_REQ_SEL_INVALID (31<<CSR_REQ_SEL_SHIFT) +#define CSR_WCOUNT_SHIFT 2 +#define CSR_WCOUNT_MASK 0xFFFC + +#define APB_DMA_CHAN_STA 0x004 +#define STA_BUSY (1<<31) +#define STA_ISE_EOC (1<<30) +#define STA_HALT (1<<29) +#define STA_PING_PONG (1<<28) +#define STA_COUNT_SHIFT 2 +#define STA_COUNT_MASK 0xFFFC + +#define APB_DMA_CHAN_AHB_PTR 0x010 + +#define APB_DMA_CHAN_AHB_SEQ 0x014 +#define AHB_SEQ_INTR_ENB (1<<31) +#define AHB_SEQ_BUS_WIDTH_SHIFT 28 +#define AHB_SEQ_BUS_WIDTH_MASK (0x7<<AHB_SEQ_BUS_WIDTH_SHIFT) +#define AHB_SEQ_BUS_WIDTH_8 (0<<AHB_SEQ_BUS_WIDTH_SHIFT) +#define AHB_SEQ_BUS_WIDTH_16 (1<<AHB_SEQ_BUS_WIDTH_SHIFT) +#define AHB_SEQ_BUS_WIDTH_32 (2<<AHB_SEQ_BUS_WIDTH_SHIFT) +#define AHB_SEQ_BUS_WIDTH_64 (3<<AHB_SEQ_BUS_WIDTH_SHIFT) +#define AHB_SEQ_BUS_WIDTH_128 (4<<AHB_SEQ_BUS_WIDTH_SHIFT) +#define AHB_SEQ_DATA_SWAP (1<<27) +#define AHB_SEQ_BURST_MASK (0x7<<24) +#define AHB_SEQ_BURST_1 (4<<24) +#define AHB_SEQ_BURST_4 (5<<24) +#define AHB_SEQ_BURST_8 (6<<24) +#define AHB_SEQ_DBL_BUF (1<<19) +#define AHB_SEQ_WRAP_SHIFT 16 +#define AHB_SEQ_WRAP_MASK (0x7<<AHB_SEQ_WRAP_SHIFT) + +#define APB_DMA_CHAN_APB_PTR 0x018 + +#define APB_DMA_CHAN_APB_SEQ 0x01c +#define APB_SEQ_BUS_WIDTH_SHIFT 28 +#define APB_SEQ_BUS_WIDTH_MASK (0x7<<APB_SEQ_BUS_WIDTH_SHIFT) +#define APB_SEQ_BUS_WIDTH_8 (0<<APB_SEQ_BUS_WIDTH_SHIFT) +#define APB_SEQ_BUS_WIDTH_16 (1<<APB_SEQ_BUS_WIDTH_SHIFT) +#define APB_SEQ_BUS_WIDTH_32 (2<<APB_SEQ_BUS_WIDTH_SHIFT) +#define APB_SEQ_BUS_WIDTH_64 (3<<APB_SEQ_BUS_WIDTH_SHIFT) +#define APB_SEQ_BUS_WIDTH_128 (4<<APB_SEQ_BUS_WIDTH_SHIFT) +#define APB_SEQ_DATA_SWAP (1<<27) +#define APB_SEQ_WRAP_SHIFT 16 +#define APB_SEQ_WRAP_MASK (0x7<<APB_SEQ_WRAP_SHIFT) + +#define TEGRA_SYSTEM_DMA_CH_NR 16 +#define TEGRA_SYSTEM_DMA_AVP_CH_NUM 4 +#define TEGRA_SYSTEM_DMA_CH_MIN 0 +#define TEGRA_SYSTEM_DMA_CH_MAX \ + (TEGRA_SYSTEM_DMA_CH_NR - TEGRA_SYSTEM_DMA_AVP_CH_NUM - 1) + +#define NV_DMA_MAX_TRASFER_SIZE 0x10000 + +const unsigned int ahb_addr_wrap_table[8] = { + 0, 32, 64, 128, 256, 512, 1024, 2048 +}; + +const unsigned int apb_addr_wrap_table[8] = {0, 1, 2, 4, 8, 16, 32, 64}; + +const unsigned int bus_width_table[5] = {8, 16, 32, 64, 128}; + +#define TEGRA_DMA_NAME_SIZE 16 +struct tegra_dma_channel { + struct list_head list; + int id; + spinlock_t lock; + char name[TEGRA_DMA_NAME_SIZE]; + void __iomem *addr; + int mode; + int irq; + + /* Register shadow */ + u32 csr; + u32 ahb_seq; + u32 ahb_ptr; + u32 apb_seq; + u32 apb_ptr; +}; + +#define NV_DMA_MAX_CHANNELS 32 + +static DECLARE_BITMAP(channel_usage, NV_DMA_MAX_CHANNELS); +static struct tegra_dma_channel dma_channels[NV_DMA_MAX_CHANNELS]; + +static void tegra_dma_update_hw(struct tegra_dma_channel *ch, + struct tegra_dma_req *req); +static void tegra_dma_update_hw_partial(struct tegra_dma_channel *ch, + struct tegra_dma_req *req); +static void tegra_dma_init_hw(struct tegra_dma_channel *ch); +static void tegra_dma_stop(struct tegra_dma_channel *ch); + +void tegra_dma_flush(struct tegra_dma_channel *ch) +{ +} +EXPORT_SYMBOL(tegra_dma_flush); + +void tegra_dma_dequeue(struct tegra_dma_channel *ch) +{ + struct tegra_dma_req *req; + + req = list_entry(ch->list.next, typeof(*req), node); + + tegra_dma_dequeue_req(ch, req); + return; +} + +void tegra_dma_stop(struct tegra_dma_channel *ch) +{ + unsigned int csr; + unsigned int status; + + csr = ch->csr; + csr &= ~CSR_IE_EOC; + writel(csr, ch->addr + APB_DMA_CHAN_CSR); + + csr &= ~CSR_ENB; + writel(csr, ch->addr + APB_DMA_CHAN_CSR); + + status = readl(ch->addr + APB_DMA_CHAN_STA); + if (status & STA_ISE_EOC) + writel(status, ch->addr + APB_DMA_CHAN_STA); +} + +int tegra_dma_cancel(struct tegra_dma_channel *ch) +{ + unsigned int csr; + unsigned long irq_flags; + + spin_lock_irqsave(&ch->lock, irq_flags); + while (!list_empty(&ch->list)) + list_del(ch->list.next); + + csr = ch->csr; + csr &= ~CSR_REQ_SEL_MASK; + csr |= CSR_REQ_SEL_INVALID; + + /* Set the enable as that is not shadowed */ + csr |= CSR_ENB; + writel(csr, ch->addr + APB_DMA_CHAN_CSR); + + tegra_dma_stop(ch); + + spin_unlock_irqrestore(&ch->lock, irq_flags); + return 0; +} + +int tegra_dma_dequeue_req(struct tegra_dma_channel *ch, + struct tegra_dma_req *_req) +{ + unsigned int csr; + unsigned int status; + struct tegra_dma_req *req = NULL; + int found = 0; + unsigned long irq_flags; + int to_transfer; + int req_transfer_count; + + spin_lock_irqsave(&ch->lock, irq_flags); + list_for_each_entry(req, &ch->list, node) { + if (req == _req) { + list_del(&req->node); + found = 1; + break; + } + } + if (!found) { + spin_unlock_irqrestore(&ch->lock, irq_flags); + return 0; + } + + /* STOP the DMA and get the transfer count. + * Getting the transfer count is tricky. + * - Change the source selector to invalid to stop the DMA from + * FIFO to memory. + * - Read the status register to know the number of pending + * bytes to be transfered. + * - Finally stop or program the DMA to the next buffer in the + * list. + */ + csr = ch->csr; + csr &= ~CSR_REQ_SEL_MASK; + csr |= CSR_REQ_SEL_INVALID; + + /* Set the enable as that is not shadowed */ + csr |= CSR_ENB; + writel(csr, ch->addr + APB_DMA_CHAN_CSR); + + /* Get the transfer count */ + status = readl(ch->addr + APB_DMA_CHAN_STA); + to_transfer = (status & STA_COUNT_MASK) >> STA_COUNT_SHIFT; + req_transfer_count = (ch->csr & CSR_WCOUNT_MASK) >> CSR_WCOUNT_SHIFT; + req_transfer_count += 1; + to_transfer += 1; + + req->bytes_transferred = req_transfer_count; + + if (status & STA_BUSY) + req->bytes_transferred -= to_transfer; + + /* In continous transfer mode, DMA only tracks the count of the + * half DMA buffer. So, if the DMA already finished half the DMA + * then add the half buffer to the completed count. + * + * FIXME: There can be a race here. What if the req to + * dequue happens at the same time as the DMA just moved to + * the new buffer and SW didn't yet received the interrupt? + */ + if (ch->mode & TEGRA_DMA_MODE_CONTINOUS) + if (req->buffer_status == TEGRA_DMA_REQ_BUF_STATUS_HALF_FULL) + req->bytes_transferred += req_transfer_count; + + req->bytes_transferred *= 4; + + tegra_dma_stop(ch); + if (!list_empty(&ch->list)) { + /* if the list is not empty, queue the next request */ + struct tegra_dma_req *next_req; + next_req = list_entry(ch->list.next, + typeof(*next_req), node); + tegra_dma_update_hw(ch, next_req); + } + req->status = -TEGRA_DMA_REQ_ERROR_ABORTED; + + spin_unlock_irqrestore(&ch->lock, irq_flags); + + /* Callback should be called without any lock */ + req->complete(req); + return 0; +} +EXPORT_SYMBOL(tegra_dma_dequeue_req); + +bool tegra_dma_is_empty(struct tegra_dma_channel *ch) +{ + unsigned long irq_flags; + bool is_empty; + + spin_lock_irqsave(&ch->lock, irq_flags); + if (list_empty(&ch->list)) + is_empty = true; + else + is_empty = false; + spin_unlock_irqrestore(&ch->lock, irq_flags); + return is_empty; +} +EXPORT_SYMBOL(tegra_dma_is_empty); + +bool tegra_dma_is_req_inflight(struct tegra_dma_channel *ch, + struct tegra_dma_req *_req) +{ + unsigned long irq_flags; + struct tegra_dma_req *req; + + spin_lock_irqsave(&ch->lock, irq_flags); + list_for_each_entry(req, &ch->list, node) { + if (req == _req) { + spin_unlock_irqrestore(&ch->lock, irq_flags); + return true; + } + } + spin_unlock_irqrestore(&ch->lock, irq_flags); + return false; +} +EXPORT_SYMBOL(tegra_dma_is_req_inflight); + +int tegra_dma_enqueue_req(struct tegra_dma_channel *ch, + struct tegra_dma_req *req) +{ + unsigned long irq_flags; + int start_dma = 0; + + if (req->size > NV_DMA_MAX_TRASFER_SIZE || + req->source_addr & 0x3 || req->dest_addr & 0x3) { + pr_err("Invalid DMA request for channel %d\n", ch->id); + return -EINVAL; + } + + spin_lock_irqsave(&ch->lock, irq_flags); + + req->bytes_transferred = 0; + req->status = 0; + req->buffer_status = 0; + if (list_empty(&ch->list)) + start_dma = 1; + + list_add_tail(&req->node, &ch->list); + + if (start_dma) + tegra_dma_update_hw(ch, req); + + spin_unlock_irqrestore(&ch->lock, irq_flags); + + return 0; +} +EXPORT_SYMBOL(tegra_dma_enqueue_req); + +struct tegra_dma_channel *tegra_dma_allocate_channel(int mode) +{ + int channel; + struct tegra_dma_channel *ch; + + /* first channel is the shared channel */ + if (mode & TEGRA_DMA_SHARED) { + channel = TEGRA_SYSTEM_DMA_CH_MIN; + } else { + channel = find_first_zero_bit(channel_usage, + ARRAY_SIZE(dma_channels)); + if (channel >= ARRAY_SIZE(dma_channels)) + return NULL; + } + __set_bit(channel, channel_usage); + ch = &dma_channels[channel]; + ch->mode = mode; + return ch; +} +EXPORT_SYMBOL(tegra_dma_allocate_channel); + +void tegra_dma_free_channel(struct tegra_dma_channel *ch) +{ + if (ch->mode & TEGRA_DMA_SHARED) + return; + tegra_dma_cancel(ch); + __clear_bit(ch->id, channel_usage); +} +EXPORT_SYMBOL(tegra_dma_free_channel); + +static void tegra_dma_update_hw_partial(struct tegra_dma_channel *ch, + struct tegra_dma_req *req) +{ + if (req->to_memory) { + ch->apb_ptr = req->source_addr; + ch->ahb_ptr = req->dest_addr; + } else { + ch->apb_ptr = req->dest_addr; + ch->ahb_ptr = req->source_addr; + } + writel(ch->apb_ptr, ch->addr + APB_DMA_CHAN_APB_PTR); + writel(ch->ahb_ptr, ch->addr + APB_DMA_CHAN_AHB_PTR); + + req->status = TEGRA_DMA_REQ_INFLIGHT; + return; +} + +static void tegra_dma_update_hw(struct tegra_dma_channel *ch, + struct tegra_dma_req *req) +{ + int ahb_addr_wrap; + int apb_addr_wrap; + int ahb_bus_width; + int apb_bus_width; + int index; + unsigned long csr; + + + ch->csr |= CSR_FLOW; + ch->csr &= ~CSR_REQ_SEL_MASK; + ch->csr |= req->req_sel << CSR_REQ_SEL_SHIFT; + ch->ahb_seq &= ~AHB_SEQ_BURST_MASK; + ch->ahb_seq |= AHB_SEQ_BURST_1; + + /* One shot mode is always single buffered, + * continuous mode is always double buffered + * */ + if (ch->mode & TEGRA_DMA_MODE_ONESHOT) { + ch->csr |= CSR_ONCE; + ch->ahb_seq &= ~AHB_SEQ_DBL_BUF; + ch->csr &= ~CSR_WCOUNT_MASK; + ch->csr |= ((req->size>>2) - 1) << CSR_WCOUNT_SHIFT; + } else { + ch->csr &= ~CSR_ONCE; + ch->ahb_seq |= AHB_SEQ_DBL_BUF; + + /* In double buffered mode, we set the size to half the + * requested size and interrupt when half the buffer + * is full */ + ch->csr &= ~CSR_WCOUNT_MASK; + ch->csr |= ((req->size>>3) - 1) << CSR_WCOUNT_SHIFT; + } + + if (req->to_memory) { + ch->csr &= ~CSR_DIR; + ch->apb_ptr = req->source_addr; + ch->ahb_ptr = req->dest_addr; + + apb_addr_wrap = req->source_wrap; + ahb_addr_wrap = req->dest_wrap; + apb_bus_width = req->source_bus_width; + ahb_bus_width = req->dest_bus_width; + + } else { + ch->csr |= CSR_DIR; + ch->apb_ptr = req->dest_addr; + ch->ahb_ptr = req->source_addr; + + apb_addr_wrap = req->dest_wrap; + ahb_addr_wrap = req->source_wrap; + apb_bus_width = req->dest_bus_width; + ahb_bus_width = req->source_bus_width; + } + + apb_addr_wrap >>= 2; + ahb_addr_wrap >>= 2; + + /* set address wrap for APB size */ + index = 0; + do { + if (apb_addr_wrap_table[index] == apb_addr_wrap) + break; + index++; + } while (index < ARRAY_SIZE(apb_addr_wrap_table)); + BUG_ON(index == ARRAY_SIZE(apb_addr_wrap_table)); + ch->apb_seq &= ~APB_SEQ_WRAP_MASK; + ch->apb_seq |= index << APB_SEQ_WRAP_SHIFT; + + /* set address wrap for AHB size */ + index = 0; + do { + if (ahb_addr_wrap_table[index] == ahb_addr_wrap) + break; + index++; + } while (index < ARRAY_SIZE(ahb_addr_wrap_table)); + BUG_ON(index == ARRAY_SIZE(ahb_addr_wrap_table)); + ch->ahb_seq &= ~AHB_SEQ_WRAP_MASK; + ch->ahb_seq |= index << AHB_SEQ_WRAP_SHIFT; + + for (index = 0; index < ARRAY_SIZE(bus_width_table); index++) { + if (bus_width_table[index] == ahb_bus_width) + break; + } + BUG_ON(index == ARRAY_SIZE(bus_width_table)); + ch->ahb_seq &= ~AHB_SEQ_BUS_WIDTH_MASK; + ch->ahb_seq |= index << AHB_SEQ_BUS_WIDTH_SHIFT; + + for (index = 0; index < ARRAY_SIZE(bus_width_table); index++) { + if (bus_width_table[index] == apb_bus_width) + break; + } + BUG_ON(index == ARRAY_SIZE(bus_width_table)); + ch->apb_seq &= ~APB_SEQ_BUS_WIDTH_MASK; + ch->apb_seq |= index << APB_SEQ_BUS_WIDTH_SHIFT; + + ch->csr |= CSR_IE_EOC; + + /* update hw registers with the shadow */ + writel(ch->csr, ch->addr + APB_DMA_CHAN_CSR); + writel(ch->apb_seq, ch->addr + APB_DMA_CHAN_APB_SEQ); + writel(ch->apb_ptr, ch->addr + APB_DMA_CHAN_APB_PTR); + writel(ch->ahb_seq, ch->addr + APB_DMA_CHAN_AHB_SEQ); + writel(ch->ahb_ptr, ch->addr + APB_DMA_CHAN_AHB_PTR); + + csr = ch->csr | CSR_ENB; + writel(csr, ch->addr + APB_DMA_CHAN_CSR); + + req->status = TEGRA_DMA_REQ_INFLIGHT; +} + +static void tegra_dma_init_hw(struct tegra_dma_channel *ch) +{ + /* One shot with an interrupt to CPU after transfer */ + ch->csr = CSR_ONCE | CSR_IE_EOC; + ch->ahb_seq = AHB_SEQ_BUS_WIDTH_32 | AHB_SEQ_INTR_ENB; + ch->apb_seq = APB_SEQ_BUS_WIDTH_32 | 1 << APB_SEQ_WRAP_SHIFT; +} + +static void handle_oneshot_dma(struct tegra_dma_channel *ch) +{ + struct tegra_dma_req *req; + + spin_lock(&ch->lock); + if (list_empty(&ch->list)) { + spin_unlock(&ch->lock); + return; + } + + req = list_entry(ch->list.next, typeof(*req), node); + if (req) { + int bytes_transferred; + + bytes_transferred = + (ch->csr & CSR_WCOUNT_MASK) >> CSR_WCOUNT_SHIFT; + bytes_transferred += 1; + bytes_transferred <<= 2; + + list_del(&req->node); + req->bytes_transferred = bytes_transferred; + req->status = TEGRA_DMA_REQ_SUCCESS; + + spin_unlock(&ch->lock); + /* Callback should be called without any lock */ + pr_debug("%s: transferred %d bytes\n", __func__, + req->bytes_transferred); + req->complete(req); + spin_lock(&ch->lock); + } + + if (!list_empty(&ch->list)) { + req = list_entry(ch->list.next, typeof(*req), node); + /* the complete function we just called may have enqueued + another req, in which case dma has already started */ + if (req->status != TEGRA_DMA_REQ_INFLIGHT) + tegra_dma_update_hw(ch, req); + } + spin_unlock(&ch->lock); +} + +static void handle_continuous_dma(struct tegra_dma_channel *ch) +{ + struct tegra_dma_req *req; + + spin_lock(&ch->lock); + if (list_empty(&ch->list)) { + spin_unlock(&ch->lock); + return; + } + + req = list_entry(ch->list.next, typeof(*req), node); + if (req) { + if (req->buffer_status == TEGRA_DMA_REQ_BUF_STATUS_EMPTY) { + /* Load the next request into the hardware, if available + * */ + if (!list_is_last(&req->node, &ch->list)) { + struct tegra_dma_req *next_req; + + next_req = list_entry(req->node.next, + typeof(*next_req), node); + tegra_dma_update_hw_partial(ch, next_req); + } + req->buffer_status = TEGRA_DMA_REQ_BUF_STATUS_HALF_FULL; + req->status = TEGRA_DMA_REQ_SUCCESS; + /* DMA lock is NOT held when callback is called */ + spin_unlock(&ch->lock); + if (likely(req->threshold)) + req->threshold(req); + return; + + } else if (req->buffer_status == + TEGRA_DMA_REQ_BUF_STATUS_HALF_FULL) { + /* Callback when the buffer is completely full (i.e on + * the second interrupt */ + int bytes_transferred; + + bytes_transferred = + (ch->csr & CSR_WCOUNT_MASK) >> CSR_WCOUNT_SHIFT; + bytes_transferred += 1; + bytes_transferred <<= 3; + + req->buffer_status = TEGRA_DMA_REQ_BUF_STATUS_FULL; + req->bytes_transferred = bytes_transferred; + req->status = TEGRA_DMA_REQ_SUCCESS; + list_del(&req->node); + + /* DMA lock is NOT held when callbak is called */ + spin_unlock(&ch->lock); + req->complete(req); + return; + + } else { + BUG(); + } + } + spin_unlock(&ch->lock); +} + +static irqreturn_t dma_isr(int irq, void *data) +{ + struct tegra_dma_channel *ch = data; + unsigned long status; + + status = readl(ch->addr + APB_DMA_CHAN_STA); + if (status & STA_ISE_EOC) + writel(status, ch->addr + APB_DMA_CHAN_STA); + else { + pr_warning("Got a spurious ISR for DMA channel %d\n", ch->id); + return IRQ_HANDLED; + } + return IRQ_WAKE_THREAD; +} + +static irqreturn_t dma_thread_fn(int irq, void *data) +{ + struct tegra_dma_channel *ch = data; + + if (ch->mode & TEGRA_DMA_MODE_ONESHOT) + handle_oneshot_dma(ch); + else + handle_continuous_dma(ch); + + + return IRQ_HANDLED; +} + +int __init tegra_dma_init(void) +{ + int ret = 0; + int i; + unsigned int irq; + void __iomem *addr; + + addr = IO_ADDRESS(TEGRA_APB_DMA_BASE); + writel(GEN_ENABLE, addr + APB_DMA_GEN); + writel(0, addr + APB_DMA_CNTRL); + writel(0xFFFFFFFFul >> (31 - TEGRA_SYSTEM_DMA_CH_MAX), + addr + APB_DMA_IRQ_MASK_SET); + + memset(channel_usage, 0, sizeof(channel_usage)); + memset(dma_channels, 0, sizeof(dma_channels)); + + /* Reserve all the channels we are not supposed to touch */ + for (i = 0; i < TEGRA_SYSTEM_DMA_CH_MIN; i++) + __set_bit(i, channel_usage); + + for (i = TEGRA_SYSTEM_DMA_CH_MIN; i <= TEGRA_SYSTEM_DMA_CH_MAX; i++) { + struct tegra_dma_channel *ch = &dma_channels[i]; + + __clear_bit(i, channel_usage); + + ch->id = i; + snprintf(ch->name, TEGRA_DMA_NAME_SIZE, "dma_channel_%d", i); + + ch->addr = IO_ADDRESS(TEGRA_APB_DMA_CH0_BASE + + TEGRA_APB_DMA_CH0_SIZE * i); + + spin_lock_init(&ch->lock); + INIT_LIST_HEAD(&ch->list); + tegra_dma_init_hw(ch); + + irq = INT_APB_DMA_CH0 + i; + ret = request_threaded_irq(irq, dma_isr, dma_thread_fn, 0, + dma_channels[i].name, ch); + if (ret) { + pr_err("Failed to register IRQ %d for DMA %d\n", + irq, i); + goto fail; + } + ch->irq = irq; + } + /* mark the shared channel allocated */ + __set_bit(TEGRA_SYSTEM_DMA_CH_MIN, channel_usage); + + for (i = TEGRA_SYSTEM_DMA_CH_MAX+1; i < NV_DMA_MAX_CHANNELS; i++) + __set_bit(i, channel_usage); + + return ret; +fail: + writel(0, addr + APB_DMA_GEN); + for (i = TEGRA_SYSTEM_DMA_CH_MIN; i <= TEGRA_SYSTEM_DMA_CH_MAX; i++) { + struct tegra_dma_channel *ch = &dma_channels[i]; + if (ch->irq) + free_irq(ch->irq, ch); + } + return ret; +} + +#ifdef CONFIG_PM +static u32 apb_dma[5*TEGRA_SYSTEM_DMA_CH_NR + 3]; + +void tegra_dma_suspend(void) +{ + void __iomem *addr = IO_ADDRESS(TEGRA_APB_DMA_BASE); + u32 *ctx = apb_dma; + int i; + + *ctx++ = readl(addr + APB_DMA_GEN); + *ctx++ = readl(addr + APB_DMA_CNTRL); + *ctx++ = readl(addr + APB_DMA_IRQ_MASK); + + for (i = 0; i < TEGRA_SYSTEM_DMA_CH_NR; i++) { + addr = IO_ADDRESS(TEGRA_APB_DMA_CH0_BASE + + TEGRA_APB_DMA_CH0_SIZE * i); + + *ctx++ = readl(addr + APB_DMA_CHAN_CSR); + *ctx++ = readl(addr + APB_DMA_CHAN_AHB_PTR); + *ctx++ = readl(addr + APB_DMA_CHAN_AHB_SEQ); + *ctx++ = readl(addr + APB_DMA_CHAN_APB_PTR); + *ctx++ = readl(addr + APB_DMA_CHAN_APB_SEQ); + } +} + +void tegra_dma_resume(void) +{ + void __iomem *addr = IO_ADDRESS(TEGRA_APB_DMA_BASE); + u32 *ctx = apb_dma; + int i; + + writel(*ctx++, addr + APB_DMA_GEN); + writel(*ctx++, addr + APB_DMA_CNTRL); + writel(*ctx++, addr + APB_DMA_IRQ_MASK); + + for (i = 0; i < TEGRA_SYSTEM_DMA_CH_NR; i++) { + addr = IO_ADDRESS(TEGRA_APB_DMA_CH0_BASE + + TEGRA_APB_DMA_CH0_SIZE * i); + + writel(*ctx++, addr + APB_DMA_CHAN_CSR); + writel(*ctx++, addr + APB_DMA_CHAN_AHB_PTR); + writel(*ctx++, addr + APB_DMA_CHAN_AHB_SEQ); + writel(*ctx++, addr + APB_DMA_CHAN_APB_PTR); + writel(*ctx++, addr + APB_DMA_CHAN_APB_SEQ); + } +} + +#endif diff --git a/arch/arm/mach-tegra/include/mach/dma.h b/arch/arm/mach-tegra/include/mach/dma.h new file mode 100644 index 000000000000..39011bd9a925 --- /dev/null +++ b/arch/arm/mach-tegra/include/mach/dma.h @@ -0,0 +1,155 @@ +/* + * arch/arm/mach-tegra/include/mach/dma.h + * + * Copyright (c) 2008-2009, NVIDIA Corporation. + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#ifndef __MACH_TEGRA_DMA_H +#define __MACH_TEGRA_DMA_H + +#include <linux/list.h> + +#if defined(CONFIG_TEGRA_SYSTEM_DMA) + +struct tegra_dma_req; +struct tegra_dma_channel; + +#define TEGRA_DMA_REQ_SEL_CNTR 0 +#define TEGRA_DMA_REQ_SEL_I2S_2 1 +#define TEGRA_DMA_REQ_SEL_I2S_1 2 +#define TEGRA_DMA_REQ_SEL_SPD_I 3 +#define TEGRA_DMA_REQ_SEL_UI_I 4 +#define TEGRA_DMA_REQ_SEL_MIPI 5 +#define TEGRA_DMA_REQ_SEL_I2S2_2 6 +#define TEGRA_DMA_REQ_SEL_I2S2_1 7 +#define TEGRA_DMA_REQ_SEL_UARTA 8 +#define TEGRA_DMA_REQ_SEL_UARTB 9 +#define TEGRA_DMA_REQ_SEL_UARTC 10 +#define TEGRA_DMA_REQ_SEL_SPI 11 +#define TEGRA_DMA_REQ_SEL_AC97 12 +#define TEGRA_DMA_REQ_SEL_ACMODEM 13 +#define TEGRA_DMA_REQ_SEL_SL4B 14 +#define TEGRA_DMA_REQ_SEL_SL2B1 15 +#define TEGRA_DMA_REQ_SEL_SL2B2 16 +#define TEGRA_DMA_REQ_SEL_SL2B3 17 +#define TEGRA_DMA_REQ_SEL_SL2B4 18 +#define TEGRA_DMA_REQ_SEL_UARTD 19 +#define TEGRA_DMA_REQ_SEL_UARTE 20 +#define TEGRA_DMA_REQ_SEL_I2C 21 +#define TEGRA_DMA_REQ_SEL_I2C2 22 +#define TEGRA_DMA_REQ_SEL_I2C3 23 +#define TEGRA_DMA_REQ_SEL_DVC_I2C 24 +#define TEGRA_DMA_REQ_SEL_OWR 25 +#define TEGRA_DMA_REQ_SEL_INVALID 31 + +enum tegra_dma_mode { + TEGRA_DMA_SHARED = 1, + TEGRA_DMA_MODE_CONTINOUS = 2, + TEGRA_DMA_MODE_ONESHOT = 4, +}; + +enum tegra_dma_req_error { + TEGRA_DMA_REQ_SUCCESS = 0, + TEGRA_DMA_REQ_ERROR_ABORTED, + TEGRA_DMA_REQ_INFLIGHT, +}; + +enum tegra_dma_req_buff_status { + TEGRA_DMA_REQ_BUF_STATUS_EMPTY = 0, + TEGRA_DMA_REQ_BUF_STATUS_HALF_FULL, + TEGRA_DMA_REQ_BUF_STATUS_FULL, +}; + +struct tegra_dma_req { + struct list_head node; + unsigned int modid; + int instance; + + /* Called when the req is complete and from the DMA ISR context. + * When this is called the req structure is no longer queued by + * the DMA channel. + * + * State of the DMA depends on the number of req it has. If there are + * no DMA requests queued up, then it will STOP the DMA. It there are + * more requests in the DMA, then it will queue the next request. + */ + void (*complete)(struct tegra_dma_req *req); + + /* This is a called from the DMA ISR context when the DMA is still in + * progress and is actively filling same buffer. + * + * In case of continous mode receive, this threshold is 1/2 the buffer + * size. In other cases, this will not even be called as there is no + * hardware support for it. + * + * In the case of continous mode receive, if there is next req already + * queued, DMA programs the HW to use that req when this req is + * completed. If there is no "next req" queued, then DMA ISR doesn't do + * anything before calling this callback. + * + * This is mainly used by the cases, where the clients has queued + * only one req and want to get some sort of DMA threshold + * callback to program the next buffer. + * + */ + void (*threshold)(struct tegra_dma_req *req); + + /* 1 to copy to memory. + * 0 to copy from the memory to device FIFO */ + int to_memory; + + void *virt_addr; + + unsigned long source_addr; + unsigned long dest_addr; + unsigned long dest_wrap; + unsigned long source_wrap; + unsigned long source_bus_width; + unsigned long dest_bus_width; + unsigned long req_sel; + unsigned int size; + + /* Updated by the DMA driver on the conpletion of the request. */ + int bytes_transferred; + int status; + + /* DMA completion tracking information */ + int buffer_status; + + /* Client specific data */ + void *dev; +}; + +int tegra_dma_enqueue_req(struct tegra_dma_channel *ch, + struct tegra_dma_req *req); +int tegra_dma_dequeue_req(struct tegra_dma_channel *ch, + struct tegra_dma_req *req); +void tegra_dma_dequeue(struct tegra_dma_channel *ch); +void tegra_dma_flush(struct tegra_dma_channel *ch); + +bool tegra_dma_is_req_inflight(struct tegra_dma_channel *ch, + struct tegra_dma_req *req); +bool tegra_dma_is_empty(struct tegra_dma_channel *ch); + +struct tegra_dma_channel *tegra_dma_allocate_channel(int mode); +void tegra_dma_free_channel(struct tegra_dma_channel *ch); + +int __init tegra_dma_init(void); + +#endif + +#endif |