leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity
37ff5252b3
linux/drivers/dma/at_hdmac_regs.h
Torsten Fleischer bdf6c79278 dmaengine: at_hdmac: Fix calculation of the residual bytes 
This patch fixes the following issues regarding to the calculation of the
residue:

1. The residue is always calculated for the current transfer even if the
cookie is associated to a pending transfer.

2. For scatter/gather DMA the calculation of the residue for the current
transfer doesn't include the bytes of the child descriptors that are already
transferred.
It only calculates the difference between the transfer's total length minus
the number of bytes that are already transferred for the current child
descriptor.
For example: There is a scatter/gather DMA transfer with a total length of
1 MByte. Getting the residue several times while the transfer is running shows
something like that:

1: residue = 975584
2: residue = 1002766
3: residue = 992627
4: residue = 983767
5: residue = 985694
6: residue = 1008094
7: residue = 1009741
8: residue = 1011195

3. The driver stores the residue but never resets it when starting a new
transfer.
For example: If there are two subsequent DMA transfers. The first one with
a total length of 1 MByte and the second one with a total length of 1 kByte.
Getting the residue for both transfers shows something like that:

transfer 1: residue = 975584
transfer 2: residue = 1048380

Changes from V1:
   * Fixed coding style of the multi-line comments.
   * Improved accuracy of the residue calculation when the transfer for the
     first descriptor is active.

Changes from V2:
   * Member 'tx_width' of 'struct at_desc' restored, because the transfer width
     can't be derived from the source width when using "slave_sg".
     The transfer width is needed for the calculation of the residue if either
     the transfer of the first or the last descriptor is in progress.
     In the case of a "memory_to_memory_sg" transfer (part of this patch
     series) the transfer width of both descriptors may differ. Thus it is
     required to additionally set 'tx_width' of the last descriptor.
   * Added functions for multiply used calculations.

Signed-off-by: Torsten Fleischer <torfl6749@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-03-13 14:58:31 +05:30

453 lines
15 KiB
C
Raw Blame History

/*
* Header file for the Atmel AHB DMA Controller driver
*
* Copyright (C) 2008 Atmel 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.
*/
#ifndef AT_HDMAC_REGS_H
#define AT_HDMAC_REGS_H
#include <linux/platform_data/dma-atmel.h>
#define AT_DMA_MAX_NR_CHANNELS 8
#define AT_DMA_GCFG 0x00 /* Global Configuration Register */
#define AT_DMA_IF_BIGEND(i) (0x1 << (i)) /* AHB-Lite Interface i in Big-endian mode */
#define AT_DMA_ARB_CFG (0x1 << 4) /* Arbiter mode. */
#define AT_DMA_ARB_CFG_FIXED (0x0 << 4)
#define AT_DMA_ARB_CFG_ROUND_ROBIN (0x1 << 4)
#define AT_DMA_EN 0x04 /* Controller Enable Register */
#define AT_DMA_ENABLE (0x1 << 0)
#define AT_DMA_SREQ 0x08 /* Software Single Request Register */
#define AT_DMA_SSREQ(x) (0x1 << ((x) << 1)) /* Request a source single transfer on channel x */
#define AT_DMA_DSREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination single transfer on channel x */
#define AT_DMA_CREQ 0x0C /* Software Chunk Transfer Request Register */
#define AT_DMA_SCREQ(x) (0x1 << ((x) << 1)) /* Request a source chunk transfer on channel x */
#define AT_DMA_DCREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination chunk transfer on channel x */
#define AT_DMA_LAST 0x10 /* Software Last Transfer Flag Register */
#define AT_DMA_SLAST(x) (0x1 << ((x) << 1)) /* This src rq is last tx of buffer on channel x */
#define AT_DMA_DLAST(x) (0x1 << (1 + ((x) << 1))) /* This dst rq is last tx of buffer on channel x */
#define AT_DMA_SYNC 0x14 /* Request Synchronization Register */
#define AT_DMA_SYR(h) (0x1 << (h)) /* Synchronize handshake line h */
/* Error, Chained Buffer transfer completed and Buffer transfer completed Interrupt registers */
#define AT_DMA_EBCIER 0x18 /* Enable register */
#define AT_DMA_EBCIDR 0x1C /* Disable register */
#define AT_DMA_EBCIMR 0x20 /* Mask Register */
#define AT_DMA_EBCISR 0x24 /* Status Register */
#define AT_DMA_CBTC_OFFSET 8
#define AT_DMA_ERR_OFFSET 16
#define AT_DMA_BTC(x) (0x1 << (x))
#define AT_DMA_CBTC(x) (0x1 << (AT_DMA_CBTC_OFFSET + (x)))
#define AT_DMA_ERR(x) (0x1 << (AT_DMA_ERR_OFFSET + (x)))
#define AT_DMA_CHER 0x28 /* Channel Handler Enable Register */
#define AT_DMA_ENA(x) (0x1 << (x))
#define AT_DMA_SUSP(x) (0x1 << ( 8 + (x)))
#define AT_DMA_KEEP(x) (0x1 << (24 + (x)))
#define AT_DMA_CHDR 0x2C /* Channel Handler Disable Register */
#define AT_DMA_DIS(x) (0x1 << (x))
#define AT_DMA_RES(x) (0x1 << ( 8 + (x)))
#define AT_DMA_CHSR 0x30 /* Channel Handler Status Register */
#define AT_DMA_EMPT(x) (0x1 << (16 + (x)))
#define AT_DMA_STAL(x) (0x1 << (24 + (x)))
#define AT_DMA_CH_REGS_BASE 0x3C /* Channel registers base address */
#define ch_regs(x) (AT_DMA_CH_REGS_BASE + (x) * 0x28) /* Channel x base addr */
/* Hardware register offset for each channel */
#define ATC_SADDR_OFFSET 0x00 /* Source Address Register */
#define ATC_DADDR_OFFSET 0x04 /* Destination Address Register */
#define ATC_DSCR_OFFSET 0x08 /* Descriptor Address Register */
#define ATC_CTRLA_OFFSET 0x0C /* Control A Register */
#define ATC_CTRLB_OFFSET 0x10 /* Control B Register */
#define ATC_CFG_OFFSET 0x14 /* Configuration Register */
#define ATC_SPIP_OFFSET 0x18 /* Src PIP Configuration Register */
#define ATC_DPIP_OFFSET 0x1C /* Dst PIP Configuration Register */
/* Bitfield definitions */
/* Bitfields in DSCR */
#define ATC_DSCR_IF(i) (0x3 & (i)) /* Dsc feched via AHB-Lite Interface i */
/* Bitfields in CTRLA */
#define ATC_BTSIZE_MAX 0xFFFFUL /* Maximum Buffer Transfer Size */
#define ATC_BTSIZE(x) (ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
#define ATC_SCSIZE_MASK (0x7 << 16) /* Source Chunk Transfer Size */
#define ATC_SCSIZE(x) (ATC_SCSIZE_MASK & ((x) << 16))
#define ATC_SCSIZE_1 (0x0 << 16)
#define ATC_SCSIZE_4 (0x1 << 16)
#define ATC_SCSIZE_8 (0x2 << 16)
#define ATC_SCSIZE_16 (0x3 << 16)
#define ATC_SCSIZE_32 (0x4 << 16)
#define ATC_SCSIZE_64 (0x5 << 16)
#define ATC_SCSIZE_128 (0x6 << 16)
#define ATC_SCSIZE_256 (0x7 << 16)
#define ATC_DCSIZE_MASK (0x7 << 20) /* Destination Chunk Transfer Size */
#define ATC_DCSIZE(x) (ATC_DCSIZE_MASK & ((x) << 20))
#define ATC_DCSIZE_1 (0x0 << 20)
#define ATC_DCSIZE_4 (0x1 << 20)
#define ATC_DCSIZE_8 (0x2 << 20)
#define ATC_DCSIZE_16 (0x3 << 20)
#define ATC_DCSIZE_32 (0x4 << 20)
#define ATC_DCSIZE_64 (0x5 << 20)
#define ATC_DCSIZE_128 (0x6 << 20)
#define ATC_DCSIZE_256 (0x7 << 20)
#define ATC_SRC_WIDTH_MASK (0x3 << 24) /* Source Single Transfer Size */
#define ATC_SRC_WIDTH(x) ((x) << 24)
#define ATC_SRC_WIDTH_BYTE (0x0 << 24)
#define ATC_SRC_WIDTH_HALFWORD (0x1 << 24)
#define ATC_SRC_WIDTH_WORD (0x2 << 24)
#define ATC_DST_WIDTH_MASK (0x3 << 28) /* Destination Single Transfer Size */
#define ATC_DST_WIDTH(x) ((x) << 28)
#define ATC_DST_WIDTH_BYTE (0x0 << 28)
#define ATC_DST_WIDTH_HALFWORD (0x1 << 28)
#define ATC_DST_WIDTH_WORD (0x2 << 28)
#define ATC_DONE (0x1 << 31) /* Tx Done (only written back in descriptor) */
/* Bitfields in CTRLB */
#define ATC_SIF(i) (0x3 & (i)) /* Src tx done via AHB-Lite Interface i */
#define ATC_DIF(i) ((0x3 & (i)) << 4) /* Dst tx done via AHB-Lite Interface i */
/* Specify AHB interfaces */
#define AT_DMA_MEM_IF 0 /* interface 0 as memory interface */
#define AT_DMA_PER_IF 1 /* interface 1 as peripheral interface */
#define ATC_SRC_PIP (0x1 << 8) /* Source Picture-in-Picture enabled */
#define ATC_DST_PIP (0x1 << 12) /* Destination Picture-in-Picture enabled */
#define ATC_SRC_DSCR_DIS (0x1 << 16) /* Src Descriptor fetch disable */
#define ATC_DST_DSCR_DIS (0x1 << 20) /* Dst Descriptor fetch disable */
#define ATC_FC_MASK (0x7 << 21) /* Choose Flow Controller */
#define ATC_FC_MEM2MEM (0x0 << 21) /* Mem-to-Mem (DMA) */
#define ATC_FC_MEM2PER (0x1 << 21) /* Mem-to-Periph (DMA) */
#define ATC_FC_PER2MEM (0x2 << 21) /* Periph-to-Mem (DMA) */
#define ATC_FC_PER2PER (0x3 << 21) /* Periph-to-Periph (DMA) */
#define ATC_FC_PER2MEM_PER (0x4 << 21) /* Periph-to-Mem (Peripheral) */
#define ATC_FC_MEM2PER_PER (0x5 << 21) /* Mem-to-Periph (Peripheral) */
#define ATC_FC_PER2PER_SRCPER (0x6 << 21) /* Periph-to-Periph (Src Peripheral) */
#define ATC_FC_PER2PER_DSTPER (0x7 << 21) /* Periph-to-Periph (Dst Peripheral) */
#define ATC_SRC_ADDR_MODE_MASK (0x3 << 24)
#define ATC_SRC_ADDR_MODE_INCR (0x0 << 24) /* Incrementing Mode */
#define ATC_SRC_ADDR_MODE_DECR (0x1 << 24) /* Decrementing Mode */
#define ATC_SRC_ADDR_MODE_FIXED (0x2 << 24) /* Fixed Mode */
#define ATC_DST_ADDR_MODE_MASK (0x3 << 28)
#define ATC_DST_ADDR_MODE_INCR (0x0 << 28) /* Incrementing Mode */
#define ATC_DST_ADDR_MODE_DECR (0x1 << 28) /* Decrementing Mode */
#define ATC_DST_ADDR_MODE_FIXED (0x2 << 28) /* Fixed Mode */
#define ATC_IEN (0x1 << 30) /* BTC interrupt enable (active low) */
#define ATC_AUTO (0x1 << 31) /* Auto multiple buffer tx enable */
/* Bitfields in CFG */
/* are in at_hdmac.h */
/* Bitfields in SPIP */
#define ATC_SPIP_HOLE(x) (0xFFFFU & (x))
#define ATC_SPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)
/* Bitfields in DPIP */
#define ATC_DPIP_HOLE(x) (0xFFFFU & (x))
#define ATC_DPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)
/*-- descriptors -----------------------------------------------------*/
/* LLI == Linked List Item; aka DMA buffer descriptor */
struct at_lli {
/* values that are not changed by hardware */
dma_addr_t saddr;
dma_addr_t daddr;
/* value that may get written back: */
u32 ctrla;
/* more values that are not changed by hardware */
u32 ctrlb;
dma_addr_t dscr; /* chain to next lli */
};
/**
* struct at_desc - software descriptor
* @at_lli: hardware lli structure
* @txd: support for the async_tx api
* @desc_node: node on the channed descriptors list
* @len: descriptor byte count
* @tx_width: transfer width
* @total_len: total transaction byte count
*/
struct at_desc {
/* FIRST values the hardware uses */
struct at_lli lli;
/* THEN values for driver housekeeping */
struct list_head tx_list;
struct dma_async_tx_descriptor txd;
struct list_head desc_node;
size_t len;
u32 tx_width;
size_t total_len;
};
static inline struct at_desc *
txd_to_at_desc(struct dma_async_tx_descriptor *txd)
{
return container_of(txd, struct at_desc, txd);
}
/*-- Channels --------------------------------------------------------*/
/**
* atc_status - information bits stored in channel status flag
*
* Manipulated with atomic operations.
*/
enum atc_status {
ATC_IS_ERROR = 0,
ATC_IS_PAUSED = 1,
ATC_IS_CYCLIC = 24,
};
/**
* struct at_dma_chan - internal representation of an Atmel HDMAC channel
* @chan_common: common dmaengine channel object members
* @device: parent device
* @ch_regs: memory mapped register base
* @mask: channel index in a mask
* @per_if: peripheral interface
* @mem_if: memory interface
* @status: transmit status information from irq/prep* functions
* to tasklet (use atomic operations)
* @tasklet: bottom half to finish transaction work
* @save_cfg: configuration register that is saved on suspend/resume cycle
* @save_dscr: for cyclic operations, preserve next descriptor address in
* the cyclic list on suspend/resume cycle
* @dma_sconfig: configuration for slave transfers, passed via
* .device_config
* @lock: serializes enqueue/dequeue operations to descriptors lists
* @active_list: list of descriptors dmaengine is being running on
* @queue: list of descriptors ready to be submitted to engine
* @free_list: list of descriptors usable by the channel
* @descs_allocated: records the actual size of the descriptor pool
*/
struct at_dma_chan {
struct dma_chan chan_common;
struct at_dma *device;
void __iomem *ch_regs;
u8 mask;
u8 per_if;
u8 mem_if;
unsigned long status;
struct tasklet_struct tasklet;
u32 save_cfg;
u32 save_dscr;
struct dma_slave_config dma_sconfig;
spinlock_t lock;
/* these other elements are all protected by lock */
struct list_head active_list;
struct list_head queue;
struct list_head free_list;
unsigned int descs_allocated;
};
#define channel_readl(atchan, name) \
__raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
#define channel_writel(atchan, name, val) \
__raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
{
return container_of(dchan, struct at_dma_chan, chan_common);
}
/*
* Fix sconfig's burst size according to at_hdmac. We need to convert them as:
* 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7.
*
* This can be done by finding most significant bit set.
*/
static inline void convert_burst(u32 *maxburst)
{
if (*maxburst > 1)
*maxburst = fls(*maxburst) - 2;
else
*maxburst = 0;
}
/*
* Fix sconfig's bus width according to at_hdmac.
* 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2.
*/
static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
{
switch (addr_width) {
case DMA_SLAVE_BUSWIDTH_2_BYTES:
return 1;
case DMA_SLAVE_BUSWIDTH_4_BYTES:
return 2;
default:
/* For 1 byte width or fallback */
return 0;
}
}
/*-- Controller ------------------------------------------------------*/
/**
* struct at_dma - internal representation of an Atmel HDMA Controller
* @chan_common: common dmaengine dma_device object members
* @atdma_devtype: identifier of DMA controller compatibility
* @ch_regs: memory mapped register base
* @clk: dma controller clock
* @save_imr: interrupt mask register that is saved on suspend/resume cycle
* @all_chan_mask: all channels availlable in a mask
* @dma_desc_pool: base of DMA descriptor region (DMA address)
* @chan: channels table to store at_dma_chan structures
*/
struct at_dma {
struct dma_device dma_common;
void __iomem *regs;
struct clk *clk;
u32 save_imr;
u8 all_chan_mask;
struct dma_pool *dma_desc_pool;
/* AT THE END channels table */
struct at_dma_chan chan[0];
};
#define dma_readl(atdma, name) \
__raw_readl((atdma)->regs + AT_DMA_##name)
#define dma_writel(atdma, name, val) \
__raw_writel((val), (atdma)->regs + AT_DMA_##name)
static inline struct at_dma *to_at_dma(struct dma_device *ddev)
{
return container_of(ddev, struct at_dma, dma_common);
}
/*-- Helper functions ------------------------------------------------*/
static struct device *chan2dev(struct dma_chan *chan)
{
return &chan->dev->device;
}
#if defined(VERBOSE_DEBUG)
static void vdbg_dump_regs(struct at_dma_chan *atchan)
{
struct at_dma *atdma = to_at_dma(atchan->chan_common.device);
dev_err(chan2dev(&atchan->chan_common),
" channel %d : imr = 0x%x, chsr = 0x%x\n",
atchan->chan_common.chan_id,
dma_readl(atdma, EBCIMR),
dma_readl(atdma, CHSR));
dev_err(chan2dev(&atchan->chan_common),
" channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
channel_readl(atchan, SADDR),
channel_readl(atchan, DADDR),
channel_readl(atchan, CTRLA),
channel_readl(atchan, CTRLB),
channel_readl(atchan, CFG),
channel_readl(atchan, DSCR));
}
#else
static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
#endif
static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
{
dev_crit(chan2dev(&atchan->chan_common),
" desc: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n",
lli->saddr, lli->daddr,
lli->ctrla, lli->ctrlb, lli->dscr);
}
static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
{
u32 ebci;
/* enable interrupts on buffer transfer completion & error */
ebci = AT_DMA_BTC(chan_id)
| AT_DMA_ERR(chan_id);
if (on)
dma_writel(atdma, EBCIER, ebci);
else
dma_writel(atdma, EBCIDR, ebci);
}
static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
{
atc_setup_irq(atdma, chan_id, 1);
}
static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
{
atc_setup_irq(atdma, chan_id, 0);
}
/**
* atc_chan_is_enabled - test if given channel is enabled
* @atchan: channel we want to test status
*/
static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
{
struct at_dma *atdma = to_at_dma(atchan->chan_common.device);
return !!(dma_readl(atdma, CHSR) & atchan->mask);
}
/**
* atc_chan_is_paused - test channel pause/resume status
* @atchan: channel we want to test status
*/
static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
{
return test_bit(ATC_IS_PAUSED, &atchan->status);
}
/**
* atc_chan_is_cyclic - test if given channel has cyclic property set
* @atchan: channel we want to test status
*/
static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
{
return test_bit(ATC_IS_CYCLIC, &atchan->status);
}
/**
* set_desc_eol - set end-of-link to descriptor so it will end transfer
* @desc: descriptor, signle or at the end of a chain, to end chain on
*/
static void set_desc_eol(struct at_desc *desc)
{
u32 ctrlb = desc->lli.ctrlb;
ctrlb &= ~ATC_IEN;
ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;
desc->lli.ctrlb = ctrlb;
desc->lli.dscr = 0;
}
#endif /* AT_HDMAC_REGS_H */
Reference in New Issue View Git Blame Copy Permalink