From 999331af456bf6fc1520ea7b68b6a3dbb4af8ff6 Mon Sep 17 00:00:00 2001 From: Pavel Pisa Date: Sun, 2 Apr 2006 16:58:37 +0100 Subject: [ARM] 3444/1: i.MX: Scatter-gather DMA emulation for i.MX/MX1 Patch from Pavel Pisa This patch contains simplified set of changes to add scatter-gather emulation capability into MX1 DMA support. The result should be still usable for next combination of DMA transfers Statter-Gather/linear/2D/FIFO to linear/2D/FIFO and linear/2D/FIFO to Statter-Gather/2D/FIFO The patch corrects channel priority allocation to be compatible with MX1 hardware implementation. Previous code has not been adapted from its PXA original. Signed-off-by: Pavel Pisa Acked-by: Sascha Hauer Signed-off-by: Russell King --- include/asm-arm/arch-imx/dma.h | 17 ++----- include/asm-arm/arch-imx/imx-dma.h | 90 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 93 insertions(+), 14 deletions(-) create mode 100644 include/asm-arm/arch-imx/imx-dma.h (limited to 'include/asm-arm') diff --git a/include/asm-arm/arch-imx/dma.h b/include/asm-arm/arch-imx/dma.h index b45fa367d71..621ff2c730f 100644 --- a/include/asm-arm/arch-imx/dma.h +++ b/include/asm-arm/arch-imx/dma.h @@ -17,27 +17,16 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + #ifndef __ASM_ARCH_DMA_H #define __ASM_ARCH_DMA_H -/* - * DMA registration - */ - typedef enum { DMA_PRIO_HIGH = 0, - DMA_PRIO_MEDIUM = 3, - DMA_PRIO_LOW = 6 + DMA_PRIO_MEDIUM = 1, + DMA_PRIO_LOW = 2 } imx_dma_prio; -int imx_request_dma(char *name, imx_dma_prio prio, - void (*irq_handler) (int, void *, struct pt_regs *), - void (*err_handler) (int, void *, struct pt_regs *), - void *data); - -void imx_free_dma(int dma_ch); - - #define DMA_REQ_UART3_T 2 #define DMA_REQ_UART3_R 3 #define DMA_REQ_SSI2_T 4 diff --git a/include/asm-arm/arch-imx/imx-dma.h b/include/asm-arm/arch-imx/imx-dma.h new file mode 100644 index 00000000000..f2063c1d610 --- /dev/null +++ b/include/asm-arm/arch-imx/imx-dma.h @@ -0,0 +1,90 @@ +/* + * linux/include/asm-arm/imxads/dma.h + * + * Copyright (C) 1997,1998 Russell King + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include + +#ifndef __ASM_ARCH_IMX_DMA_H +#define __ASM_ARCH_IMX_DMA_H + +#define IMX_DMA_CHANNELS 11 + +/* + * struct imx_dma_channel - i.MX specific DMA extension + * @name: name specified by DMA client + * @irq_handler: client callback for end of transfer + * @err_handler: client callback for error condition + * @data: clients context data for callbacks + * @dma_mode: direction of the transfer %DMA_MODE_READ or %DMA_MODE_WRITE + * @sg: pointer to the actual read/written chunk for scatter-gather emulation + * @sgbc: counter of processed bytes in the actual read/written chunk + * @resbytes: total residual number of bytes to transfer + * (it can be lower or same as sum of SG mapped chunk sizes) + * @sgcount: number of chunks to be read/written + * + * Structure is used for IMX DMA processing. It would be probably good + * @struct dma_struct in the future for external interfacing and use + * @struct imx_dma_channel only as extension to it. + */ + +struct imx_dma_channel { + const char *name; + void (*irq_handler) (int, void *, struct pt_regs *); + void (*err_handler) (int, void *, struct pt_regs *); + void *data; + dmamode_t dma_mode; + struct scatterlist *sg; + unsigned int sgbc; + unsigned int sgcount; + unsigned int resbytes; + int dma_num; +}; + +extern struct imx_dma_channel imx_dma_channels[IMX_DMA_CHANNELS]; + + +/* The type to distinguish channel numbers parameter from ordinal int type */ +typedef int imx_dmach_t; + +int +imx_dma_setup_single(imx_dmach_t dma_ch, dma_addr_t dma_address, + unsigned int dma_length, unsigned int dev_addr, dmamode_t dmamode); + +int +imx_dma_setup_sg(imx_dmach_t dma_ch, + struct scatterlist *sg, unsigned int sgcount, unsigned int dma_length, + unsigned int dev_addr, dmamode_t dmamode); + +int +imx_dma_setup_handlers(imx_dmach_t dma_ch, + void (*irq_handler) (int, void *, struct pt_regs *), + void (*err_handler) (int, void *, struct pt_regs *), void *data); + +void imx_dma_enable(imx_dmach_t dma_ch); + +void imx_dma_disable(imx_dmach_t dma_ch); + +int imx_dma_request(imx_dmach_t dma_ch, const char *name); + +void imx_dma_free(imx_dmach_t dma_ch); + +int imx_dma_request_by_prio(imx_dmach_t *pdma_ch, const char *name, imx_dma_prio prio); + + +#endif /* _ASM_ARCH_IMX_DMA_H */ -- cgit v1.2.3