cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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floppy.h (6860B)


      1/*
      2 * Architecture specific parts of the Floppy driver
      3 *
      4 * This file is subject to the terms and conditions of the GNU General Public
      5 * License.  See the file "COPYING" in the main directory of this archive
      6 * for more details.
      7 *
      8 * Copyright (C) 1995
      9 */
     10#ifndef _ASM_X86_FLOPPY_H
     11#define _ASM_X86_FLOPPY_H
     12
     13#include <linux/vmalloc.h>
     14
     15/*
     16 * The DMA channel used by the floppy controller cannot access data at
     17 * addresses >= 16MB
     18 *
     19 * Went back to the 1MB limit, as some people had problems with the floppy
     20 * driver otherwise. It doesn't matter much for performance anyway, as most
     21 * floppy accesses go through the track buffer.
     22 */
     23#define _CROSS_64KB(a, s, vdma)						\
     24	(!(vdma) &&							\
     25	 ((unsigned long)(a)/K_64 != ((unsigned long)(a) + (s) - 1) / K_64))
     26
     27#define CROSS_64KB(a, s) _CROSS_64KB(a, s, use_virtual_dma & 1)
     28
     29
     30#define SW fd_routine[use_virtual_dma & 1]
     31#define CSW fd_routine[can_use_virtual_dma & 1]
     32
     33
     34#define fd_inb(base, reg)		inb_p((base) + (reg))
     35#define fd_outb(value, base, reg)	outb_p(value, (base) + (reg))
     36
     37#define fd_request_dma()	CSW._request_dma(FLOPPY_DMA, "floppy")
     38#define fd_free_dma()		CSW._free_dma(FLOPPY_DMA)
     39#define fd_enable_irq()		enable_irq(FLOPPY_IRQ)
     40#define fd_disable_irq()	disable_irq(FLOPPY_IRQ)
     41#define fd_free_irq()		free_irq(FLOPPY_IRQ, NULL)
     42#define fd_get_dma_residue()	SW._get_dma_residue(FLOPPY_DMA)
     43#define fd_dma_mem_alloc(size)	SW._dma_mem_alloc(size)
     44#define fd_dma_setup(addr, size, mode, io) SW._dma_setup(addr, size, mode, io)
     45
     46#define FLOPPY_CAN_FALLBACK_ON_NODMA
     47
     48static int virtual_dma_count;
     49static int virtual_dma_residue;
     50static char *virtual_dma_addr;
     51static int virtual_dma_mode;
     52static int doing_pdma;
     53
     54static irqreturn_t floppy_hardint(int irq, void *dev_id)
     55{
     56	unsigned char st;
     57
     58#undef TRACE_FLPY_INT
     59
     60#ifdef TRACE_FLPY_INT
     61	static int calls;
     62	static int bytes;
     63	static int dma_wait;
     64#endif
     65	if (!doing_pdma)
     66		return floppy_interrupt(irq, dev_id);
     67
     68#ifdef TRACE_FLPY_INT
     69	if (!calls)
     70		bytes = virtual_dma_count;
     71#endif
     72
     73	{
     74		int lcount;
     75		char *lptr;
     76
     77		for (lcount = virtual_dma_count, lptr = virtual_dma_addr;
     78		     lcount; lcount--, lptr++) {
     79			st = inb(virtual_dma_port + FD_STATUS);
     80			st &= STATUS_DMA | STATUS_READY;
     81			if (st != (STATUS_DMA | STATUS_READY))
     82				break;
     83			if (virtual_dma_mode)
     84				outb_p(*lptr, virtual_dma_port + FD_DATA);
     85			else
     86				*lptr = inb_p(virtual_dma_port + FD_DATA);
     87		}
     88		virtual_dma_count = lcount;
     89		virtual_dma_addr = lptr;
     90		st = inb(virtual_dma_port + FD_STATUS);
     91	}
     92
     93#ifdef TRACE_FLPY_INT
     94	calls++;
     95#endif
     96	if (st == STATUS_DMA)
     97		return IRQ_HANDLED;
     98	if (!(st & STATUS_DMA)) {
     99		virtual_dma_residue += virtual_dma_count;
    100		virtual_dma_count = 0;
    101#ifdef TRACE_FLPY_INT
    102		printk(KERN_DEBUG "count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n",
    103		       virtual_dma_count, virtual_dma_residue, calls, bytes,
    104		       dma_wait);
    105		calls = 0;
    106		dma_wait = 0;
    107#endif
    108		doing_pdma = 0;
    109		floppy_interrupt(irq, dev_id);
    110		return IRQ_HANDLED;
    111	}
    112#ifdef TRACE_FLPY_INT
    113	if (!virtual_dma_count)
    114		dma_wait++;
    115#endif
    116	return IRQ_HANDLED;
    117}
    118
    119static void fd_disable_dma(void)
    120{
    121	if (!(can_use_virtual_dma & 1))
    122		disable_dma(FLOPPY_DMA);
    123	doing_pdma = 0;
    124	virtual_dma_residue += virtual_dma_count;
    125	virtual_dma_count = 0;
    126}
    127
    128static int vdma_request_dma(unsigned int dmanr, const char *device_id)
    129{
    130	return 0;
    131}
    132
    133static void vdma_nop(unsigned int dummy)
    134{
    135}
    136
    137
    138static int vdma_get_dma_residue(unsigned int dummy)
    139{
    140	return virtual_dma_count + virtual_dma_residue;
    141}
    142
    143
    144static int fd_request_irq(void)
    145{
    146	if (can_use_virtual_dma)
    147		return request_irq(FLOPPY_IRQ, floppy_hardint,
    148				   0, "floppy", NULL);
    149	else
    150		return request_irq(FLOPPY_IRQ, floppy_interrupt,
    151				   0, "floppy", NULL);
    152}
    153
    154static unsigned long dma_mem_alloc(unsigned long size)
    155{
    156	return __get_dma_pages(GFP_KERNEL|__GFP_NORETRY, get_order(size));
    157}
    158
    159
    160static unsigned long vdma_mem_alloc(unsigned long size)
    161{
    162	return (unsigned long)vmalloc(size);
    163
    164}
    165
    166#define nodma_mem_alloc(size) vdma_mem_alloc(size)
    167
    168static void _fd_dma_mem_free(unsigned long addr, unsigned long size)
    169{
    170	if ((unsigned long)addr >= (unsigned long)high_memory)
    171		vfree((void *)addr);
    172	else
    173		free_pages(addr, get_order(size));
    174}
    175
    176#define fd_dma_mem_free(addr, size)  _fd_dma_mem_free(addr, size)
    177
    178static void _fd_chose_dma_mode(char *addr, unsigned long size)
    179{
    180	if (can_use_virtual_dma == 2) {
    181		if ((unsigned long)addr >= (unsigned long)high_memory ||
    182		    isa_virt_to_bus(addr) >= 0x1000000 ||
    183		    _CROSS_64KB(addr, size, 0))
    184			use_virtual_dma = 1;
    185		else
    186			use_virtual_dma = 0;
    187	} else {
    188		use_virtual_dma = can_use_virtual_dma & 1;
    189	}
    190}
    191
    192#define fd_chose_dma_mode(addr, size) _fd_chose_dma_mode(addr, size)
    193
    194
    195static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
    196{
    197	doing_pdma = 1;
    198	virtual_dma_port = io;
    199	virtual_dma_mode = (mode == DMA_MODE_WRITE);
    200	virtual_dma_addr = addr;
    201	virtual_dma_count = size;
    202	virtual_dma_residue = 0;
    203	return 0;
    204}
    205
    206static int hard_dma_setup(char *addr, unsigned long size, int mode, int io)
    207{
    208#ifdef FLOPPY_SANITY_CHECK
    209	if (CROSS_64KB(addr, size)) {
    210		printk("DMA crossing 64-K boundary %p-%p\n", addr, addr+size);
    211		return -1;
    212	}
    213#endif
    214	/* actual, physical DMA */
    215	doing_pdma = 0;
    216	clear_dma_ff(FLOPPY_DMA);
    217	set_dma_mode(FLOPPY_DMA, mode);
    218	set_dma_addr(FLOPPY_DMA, isa_virt_to_bus(addr));
    219	set_dma_count(FLOPPY_DMA, size);
    220	enable_dma(FLOPPY_DMA);
    221	return 0;
    222}
    223
    224static struct fd_routine_l {
    225	int (*_request_dma)(unsigned int dmanr, const char *device_id);
    226	void (*_free_dma)(unsigned int dmanr);
    227	int (*_get_dma_residue)(unsigned int dummy);
    228	unsigned long (*_dma_mem_alloc)(unsigned long size);
    229	int (*_dma_setup)(char *addr, unsigned long size, int mode, int io);
    230} fd_routine[] = {
    231	{
    232		._request_dma		= request_dma,
    233		._free_dma		= free_dma,
    234		._get_dma_residue	= get_dma_residue,
    235		._dma_mem_alloc		= dma_mem_alloc,
    236		._dma_setup		= hard_dma_setup
    237	},
    238	{
    239		._request_dma		= vdma_request_dma,
    240		._free_dma		= vdma_nop,
    241		._get_dma_residue	= vdma_get_dma_residue,
    242		._dma_mem_alloc		= vdma_mem_alloc,
    243		._dma_setup		= vdma_dma_setup
    244	}
    245};
    246
    247
    248static int FDC1 = 0x3f0;
    249static int FDC2 = -1;
    250
    251/*
    252 * Floppy types are stored in the rtc's CMOS RAM and so rtc_lock
    253 * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
    254 * coincides with another rtc CMOS user.		Paul G.
    255 */
    256#define FLOPPY0_TYPE					\
    257({							\
    258	unsigned long flags;				\
    259	unsigned char val;				\
    260	spin_lock_irqsave(&rtc_lock, flags);		\
    261	val = (CMOS_READ(0x10) >> 4) & 15;		\
    262	spin_unlock_irqrestore(&rtc_lock, flags);	\
    263	val;						\
    264})
    265
    266#define FLOPPY1_TYPE					\
    267({							\
    268	unsigned long flags;				\
    269	unsigned char val;				\
    270	spin_lock_irqsave(&rtc_lock, flags);		\
    271	val = CMOS_READ(0x10) & 15;			\
    272	spin_unlock_irqrestore(&rtc_lock, flags);	\
    273	val;						\
    274})
    275
    276#define N_FDC 2
    277#define N_DRIVE 8
    278
    279#define EXTRA_FLOPPY_PARAMS
    280
    281#endif /* _ASM_X86_FLOPPY_H */