mirror of
git://projects.qi-hardware.com/ben-blinkenlights.git
synced 2024-11-16 23:22:50 +02:00
56 lines
1.5 KiB
C
56 lines
1.5 KiB
C
/*
|
|
* include/ubb/mmcclk.h - Calculate MMC bus clock speed
|
|
*
|
|
* Written 2013 by Werner Almesberger
|
|
* Copyright 2013 Werner Almesberger
|
|
*
|
|
* 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 UBB_MMCCLK_H
|
|
#define UBB_MMCCLK_H
|
|
|
|
#include <stdint.h>
|
|
|
|
|
|
#define BEN_PLL_CLK_HZ 336000000
|
|
|
|
|
|
/*
|
|
* By default (flags = 0), only clocks that can be used with any mode of
|
|
* operation will be generated. The following flags also include clocks ...
|
|
*/
|
|
|
|
#define MMCCLK_FLAG_RD_ONLY (1 << 0) /* not suitable for writing */
|
|
#define MMCCLK_FLAG_WR_ONLY (1 << 1) /* not suitable for reading */
|
|
#define MMCCLK_FLAG_INTERNAL (1 << 2) /* not suitable for bus use */
|
|
#define MMCCLK_FLAG_UNSAFE (1 << 3) /* that may hang the MSC */
|
|
#define MMCCLK_FLAG_ALL (1 << 4) /* that will hang the MSC */
|
|
|
|
/*
|
|
* For now, only MMCCLK_FLAG_UNSAFE and MMCCLK_FLAG_ALL are implemented, but
|
|
* further research may also reveal limits that depend on the type of
|
|
* operation.
|
|
*/
|
|
|
|
|
|
struct mmcclk {
|
|
int sys_clk_hz; /* system clock speed in Hz */
|
|
double bus_clk_hz; /* MMC bus clock in Hz */
|
|
uint32_t clkdiv; /* MSC controller clock */
|
|
uint32_t clkrt; /* bus clock divider */
|
|
unsigned flags;
|
|
};
|
|
|
|
|
|
void mmcclk_first(struct mmcclk *dsc, int sys_clk_hz, unsigned flags);
|
|
int mmcclk_next(struct mmcclk *dsc);
|
|
|
|
void mmcclk_start(struct mmcclk *dsc);
|
|
void mmcclk_stop(void);
|
|
|
|
#endif /* !UBB_MMCCLK_H */
|