cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

dma.h (4283B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef __ASM_ARM_DMA_H
      3#define __ASM_ARM_DMA_H
      4
      5/*
      6 * This is the maximum virtual address which can be DMA'd from.
      7 */
      8#ifndef CONFIG_ZONE_DMA
      9#define MAX_DMA_ADDRESS	0xffffffffUL
     10#else
     11#define MAX_DMA_ADDRESS	({ \
     12	extern phys_addr_t arm_dma_zone_size; \
     13	arm_dma_zone_size && arm_dma_zone_size < (0x10000000 - PAGE_OFFSET) ? \
     14		(PAGE_OFFSET + arm_dma_zone_size) : 0xffffffffUL; })
     15#endif
     16
     17#ifdef CONFIG_ISA_DMA_API
     18/*
     19 * This is used to support drivers written for the x86 ISA DMA API.
     20 * It should not be re-used except for that purpose.
     21 */
     22#include <linux/spinlock.h>
     23#include <linux/scatterlist.h>
     24
     25#include <mach/isa-dma.h>
     26
     27/*
     28 * The DMA modes reflect the settings for the ISA DMA controller
     29 */
     30#define DMA_MODE_MASK	 0xcc
     31
     32#define DMA_MODE_READ	 0x44
     33#define DMA_MODE_WRITE	 0x48
     34#define DMA_MODE_CASCADE 0xc0
     35#define DMA_AUTOINIT	 0x10
     36
     37extern raw_spinlock_t  dma_spin_lock;
     38
     39static inline unsigned long claim_dma_lock(void)
     40{
     41	unsigned long flags;
     42	raw_spin_lock_irqsave(&dma_spin_lock, flags);
     43	return flags;
     44}
     45
     46static inline void release_dma_lock(unsigned long flags)
     47{
     48	raw_spin_unlock_irqrestore(&dma_spin_lock, flags);
     49}
     50
     51/* Clear the 'DMA Pointer Flip Flop'.
     52 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
     53 */
     54#define clear_dma_ff(chan)
     55
     56/* Set only the page register bits of the transfer address.
     57 *
     58 * NOTE: This is an architecture specific function, and should
     59 *       be hidden from the drivers
     60 */
     61extern void set_dma_page(unsigned int chan, char pagenr);
     62
     63/* Request a DMA channel
     64 *
     65 * Some architectures may need to do allocate an interrupt
     66 */
     67extern int  request_dma(unsigned int chan, const char * device_id);
     68
     69/* Free a DMA channel
     70 *
     71 * Some architectures may need to do free an interrupt
     72 */
     73extern void free_dma(unsigned int chan);
     74
     75/* Enable DMA for this channel
     76 *
     77 * On some architectures, this may have other side effects like
     78 * enabling an interrupt and setting the DMA registers.
     79 */
     80extern void enable_dma(unsigned int chan);
     81
     82/* Disable DMA for this channel
     83 *
     84 * On some architectures, this may have other side effects like
     85 * disabling an interrupt or whatever.
     86 */
     87extern void disable_dma(unsigned int chan);
     88
     89/* Test whether the specified channel has an active DMA transfer
     90 */
     91extern int dma_channel_active(unsigned int chan);
     92
     93/* Set the DMA scatter gather list for this channel
     94 *
     95 * This should not be called if a DMA channel is enabled,
     96 * especially since some DMA architectures don't update the
     97 * DMA address immediately, but defer it to the enable_dma().
     98 */
     99extern void set_dma_sg(unsigned int chan, struct scatterlist *sg, int nr_sg);
    100
    101/* Set the DMA address for this channel
    102 *
    103 * This should not be called if a DMA channel is enabled,
    104 * especially since some DMA architectures don't update the
    105 * DMA address immediately, but defer it to the enable_dma().
    106 */
    107extern void __set_dma_addr(unsigned int chan, void *addr);
    108#define set_dma_addr(chan, addr)				\
    109	__set_dma_addr(chan, (void *)__bus_to_virt(addr))
    110
    111/* Set the DMA byte count for this channel
    112 *
    113 * This should not be called if a DMA channel is enabled,
    114 * especially since some DMA architectures don't update the
    115 * DMA count immediately, but defer it to the enable_dma().
    116 */
    117extern void set_dma_count(unsigned int chan, unsigned long count);
    118
    119/* Set the transfer direction for this channel
    120 *
    121 * This should not be called if a DMA channel is enabled,
    122 * especially since some DMA architectures don't update the
    123 * DMA transfer direction immediately, but defer it to the
    124 * enable_dma().
    125 */
    126extern void set_dma_mode(unsigned int chan, unsigned int mode);
    127
    128/* Set the transfer speed for this channel
    129 */
    130extern void set_dma_speed(unsigned int chan, int cycle_ns);
    131
    132/* Get DMA residue count. After a DMA transfer, this
    133 * should return zero. Reading this while a DMA transfer is
    134 * still in progress will return unpredictable results.
    135 * If called before the channel has been used, it may return 1.
    136 * Otherwise, it returns the number of _bytes_ left to transfer.
    137 */
    138extern int  get_dma_residue(unsigned int chan);
    139
    140#ifndef NO_DMA
    141#define NO_DMA	255
    142#endif
    143
    144#endif /* CONFIG_ISA_DMA_API */
    145
    146#ifdef CONFIG_PCI
    147extern int isa_dma_bridge_buggy;
    148#else
    149#define isa_dma_bridge_buggy    (0)
    150#endif
    151
    152#endif /* __ASM_ARM_DMA_H */