1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
|
/*-----------------------------------------------------------------------*/
/* Low level disk I/O module skeleton for FatFs (C)ChaN, 2007 */
/*-----------------------------------------------------------------------*/
/* This is a stub disk I/O module that acts as front end of the existing */
/* disk I/O modules and attach it to FatFs module with common interface. */
/*-----------------------------------------------------------------------*/
#include "../../gfx.h"
#if GFX_USE_GFILE && GFILE_NEED_PETITFS && GFX_USE_OS_CHIBIOS && !GFILE_PETITFS_EXTERNAL_LIB
#include "gfile_petitfs_wrapper.h"
#include <string.h>
#if HAL_USE_MMC_SPI && HAL_USE_SDC
#error "cannot specify both MMC_SPI and SDC drivers"
#endif
#if HAL_USE_MMC_SPI
extern MMCDriver MMCD1;
#elif HAL_USE_SDC
extern SDCDriver SDCD1;
#else
#error "MMC_SPI or SDC driver must be specified"
#endif
// WOW - Bugs galore!!! (in ChibiOS)
// Bugs:
// 1. ChibiOS DMA operations do not do the appropriate cache flushing or invalidating
// on cpu's that require it eg STM32F7 series.
// Instead they provide explicit dmaBufferInvalidate and dmaBufferFlush calls
// and rely on the user to explicitly flush the cache.
// Solution: We explicitly flush the cache after any possible DMA operation.
// 2. Unfortunately these explicit routines also have a bug. They assume that the
// specified data structure is aligned on a cache line boundary - not a good assumption.
// Solution: We increase the size provided to ChibiOS so that it does it properly.
// This assumes of course that we know the size of the cpu cache line.
#define CPU_CACHE_LINE_SIZE 32
#define CACHE_FLUSH(buf, sz) dmaBufferFlush((buf), (sz)+(CPU_CACHE_LINE_SIZE-1))
#define CACHE_INVALIDATE(buf, sz) dmaBufferInvalidate((buf), (sz)+(CPU_CACHE_LINE_SIZE-1))
/*-----------------------------------------------------------------------*/
/* Initialize a Drive */
DSTATUS disk_initialize (void) {
#if HAL_USE_MMC_SPI
/* It is initialized externally, just reads the status.*/
if (blkGetDriverState(&MMCD1) != BLK_READY)
return STA_NOINIT;
#else
/* It is initialized externally, just reads the status.*/
if (blkGetDriverState(&SDCD1) != BLK_READY)
return STA_NOINIT;
#endif
// All good
return 0;
}
/*-----------------------------------------------------------------------*/
/* Read Part Sector(s) */
static BYTE sectBuf[512];
static DWORD sectpos = -1;
DRESULT disk_readp (
BYTE* buff, /* [OUT] Pointer to the read buffer */
DWORD sector, /* [IN] Sector number */
UINT offset, /* [IN] Byte offset in the sector to start to read */
UINT count /* [IN] Number of bytes to read */
) {
if (sector != sectpos) {
#if HAL_USE_MMC_SPI
if (blkGetDriverState(&MMCD1) != BLK_READY)
return RES_NOTRDY;
if (mmcStartSequentialRead(&MMCD1, sector))
return RES_ERROR;
if (mmcSequentialRead(&MMCD1, sectBuf))
return RES_ERROR;
if (mmcStopSequentialRead(&MMCD1))
return RES_ERROR;
#else
if (blkGetDriverState(&SDCD1) != BLK_READY)
return RES_NOTRDY;
if (sdcRead(&SDCD1, sector, sectBuf, 1))
return RES_ERROR;
#endif
sectpos = sector;
CACHE_INVALIDATE(sectBuf, sizeof(sectBuf));
}
memcpy(buff, sectBuf + offset, count);
return RES_OK;
}
#endif // GFX_USE_GFILE && GFILE_NEED_PETITFS && GFX_USE_OS_CHIBIOS && !GFILE_PETITFS_EXTERNAL_LIB
|
