mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-08-20 08:58:52 +09:00
![Wolfgang Denk](/assets/img/avatar_default.png)
Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
187 lines
5.6 KiB
C
187 lines
5.6 KiB
C
/*
|
|
* Program for finding M & N values for DPLLs
|
|
* To be run on Host PC
|
|
*
|
|
* (C) Copyright 2010
|
|
* Texas Instruments, <www.ti.com>
|
|
*
|
|
* Aneesh V <aneesh@ti.com>
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
typedef unsigned int u32;
|
|
#define MAX_N 127
|
|
|
|
/*
|
|
* get_m_n_optimized() - Finds optimal DPLL multiplier(M) and divider(N)
|
|
* values based on the reference frequency, required output frequency,
|
|
* maximum tolerance for output frequency etc.
|
|
*
|
|
* target_freq_khz - output frequency required in KHz
|
|
* ref_freq_khz - reference(input) frequency in KHz
|
|
* m - pointer to computed M value
|
|
* n - pointer to computed N value
|
|
* tolerance_khz - tolerance for the output frequency. When the algorithm
|
|
* succeeds in finding vialble M and N values the corresponding output
|
|
* frequency will be in the range:
|
|
* [target_freq_khz - tolerance_khz, target_freq_khz]
|
|
*
|
|
* Formula:
|
|
* Fdpll = (2 * M * Fref) / (N + 1)
|
|
*
|
|
* Considerations for lock-time:
|
|
* - Smaller the N, better lock-time, especially lock-time will be
|
|
* - For acceptable lock-times:
|
|
* Fref / (M + 1) >= 1 MHz
|
|
*
|
|
* Considerations for power:
|
|
* - The difference in power for different N values giving the same
|
|
* output is negligible. So, we optimize for lock-time
|
|
*
|
|
* Hard-constraints:
|
|
* - N can not be greater than 127(7 bit field for representing N)
|
|
*
|
|
* Usage:
|
|
* $ gcc clocks_get_m_n.c
|
|
* $ ./a.out
|
|
*/
|
|
int get_m_n_optimized(u32 target_freq_khz, u32 ref_freq_khz, u32 *M, u32 *N)
|
|
{
|
|
u32 freq = target_freq_khz;
|
|
u32 m_optimal, n_optimal, freq_optimal = 0, freq_old;
|
|
u32 m, n;
|
|
n = 1;
|
|
while (1) {
|
|
m = target_freq_khz / ref_freq_khz / 2 * n;
|
|
freq_old = 0;
|
|
while (1) {
|
|
freq = ref_freq_khz * 2 * m / n;
|
|
if (freq > target_freq_khz) {
|
|
freq = freq_old;
|
|
m--;
|
|
break;
|
|
}
|
|
m++;
|
|
freq_old = freq;
|
|
}
|
|
if (freq > freq_optimal) {
|
|
freq_optimal = freq;
|
|
m_optimal = m;
|
|
n_optimal = n;
|
|
}
|
|
n++;
|
|
if ((freq_optimal == target_freq_khz) ||
|
|
((ref_freq_khz / n) < 1000)) {
|
|
break;
|
|
}
|
|
}
|
|
n--;
|
|
*M = m_optimal;
|
|
*N = n_optimal - 1;
|
|
printf("ref %d m %d n %d target %d locked %d\n", ref_freq_khz,
|
|
m_optimal, n_optimal - 1, target_freq_khz, freq_optimal);
|
|
return 0;
|
|
}
|
|
|
|
void main(void)
|
|
{
|
|
u32 m, n;
|
|
printf("\nMPU - 2000000\n");
|
|
get_m_n_optimized(2000000, 12000, &m, &n);
|
|
get_m_n_optimized(2000000, 13000, &m, &n);
|
|
get_m_n_optimized(2000000, 16800, &m, &n);
|
|
get_m_n_optimized(2000000, 19200, &m, &n);
|
|
get_m_n_optimized(2000000, 26000, &m, &n);
|
|
get_m_n_optimized(2000000, 27000, &m, &n);
|
|
get_m_n_optimized(2000000, 38400, &m, &n);
|
|
|
|
printf("\nMPU - 1200000\n");
|
|
get_m_n_optimized(1200000, 12000, &m, &n);
|
|
get_m_n_optimized(1200000, 13000, &m, &n);
|
|
get_m_n_optimized(1200000, 16800, &m, &n);
|
|
get_m_n_optimized(1200000, 19200, &m, &n);
|
|
get_m_n_optimized(1200000, 26000, &m, &n);
|
|
get_m_n_optimized(1200000, 27000, &m, &n);
|
|
get_m_n_optimized(1200000, 38400, &m, &n);
|
|
|
|
printf("\nMPU - 1584000\n");
|
|
get_m_n_optimized(1584000, 12000, &m, &n);
|
|
get_m_n_optimized(1584000, 13000, &m, &n);
|
|
get_m_n_optimized(1584000, 16800, &m, &n);
|
|
get_m_n_optimized(1584000, 19200, &m, &n);
|
|
get_m_n_optimized(1584000, 26000, &m, &n);
|
|
get_m_n_optimized(1584000, 27000, &m, &n);
|
|
get_m_n_optimized(1584000, 38400, &m, &n);
|
|
|
|
printf("\nCore 1600000\n");
|
|
get_m_n_optimized(1600000, 12000, &m, &n);
|
|
get_m_n_optimized(1600000, 13000, &m, &n);
|
|
get_m_n_optimized(1600000, 16800, &m, &n);
|
|
get_m_n_optimized(1600000, 19200, &m, &n);
|
|
get_m_n_optimized(1600000, 26000, &m, &n);
|
|
get_m_n_optimized(1600000, 27000, &m, &n);
|
|
get_m_n_optimized(1600000, 38400, &m, &n);
|
|
|
|
printf("\nPER 1536000\n");
|
|
get_m_n_optimized(1536000, 12000, &m, &n);
|
|
get_m_n_optimized(1536000, 13000, &m, &n);
|
|
get_m_n_optimized(1536000, 16800, &m, &n);
|
|
get_m_n_optimized(1536000, 19200, &m, &n);
|
|
get_m_n_optimized(1536000, 26000, &m, &n);
|
|
get_m_n_optimized(1536000, 27000, &m, &n);
|
|
get_m_n_optimized(1536000, 38400, &m, &n);
|
|
|
|
printf("\nIVA 1862000\n");
|
|
get_m_n_optimized(1862000, 12000, &m, &n);
|
|
get_m_n_optimized(1862000, 13000, &m, &n);
|
|
get_m_n_optimized(1862000, 16800, &m, &n);
|
|
get_m_n_optimized(1862000, 19200, &m, &n);
|
|
get_m_n_optimized(1862000, 26000, &m, &n);
|
|
get_m_n_optimized(1862000, 27000, &m, &n);
|
|
get_m_n_optimized(1862000, 38400, &m, &n);
|
|
|
|
printf("\nIVA Nitro - 1290000\n");
|
|
get_m_n_optimized(1290000, 12000, &m, &n);
|
|
get_m_n_optimized(1290000, 13000, &m, &n);
|
|
get_m_n_optimized(1290000, 16800, &m, &n);
|
|
get_m_n_optimized(1290000, 19200, &m, &n);
|
|
get_m_n_optimized(1290000, 26000, &m, &n);
|
|
get_m_n_optimized(1290000, 27000, &m, &n);
|
|
get_m_n_optimized(1290000, 38400, &m, &n);
|
|
|
|
printf("\nABE 196608 sys clk\n");
|
|
get_m_n_optimized(196608, 12000, &m, &n);
|
|
get_m_n_optimized(196608, 13000, &m, &n);
|
|
get_m_n_optimized(196608, 16800, &m, &n);
|
|
get_m_n_optimized(196608, 19200, &m, &n);
|
|
get_m_n_optimized(196608, 26000, &m, &n);
|
|
get_m_n_optimized(196608, 27000, &m, &n);
|
|
get_m_n_optimized(196608, 38400, &m, &n);
|
|
|
|
printf("\nABE 196608 32K\n");
|
|
get_m_n_optimized(196608000/4, 32768, &m, &n);
|
|
|
|
printf("\nUSB 1920000\n");
|
|
get_m_n_optimized(1920000, 12000, &m, &n);
|
|
get_m_n_optimized(1920000, 13000, &m, &n);
|
|
get_m_n_optimized(1920000, 16800, &m, &n);
|
|
get_m_n_optimized(1920000, 19200, &m, &n);
|
|
get_m_n_optimized(1920000, 26000, &m, &n);
|
|
get_m_n_optimized(1920000, 27000, &m, &n);
|
|
get_m_n_optimized(1920000, 38400, &m, &n);
|
|
|
|
printf("\nCore ES1 1523712\n");
|
|
get_m_n_optimized(1524000, 12000, &m, &n);
|
|
get_m_n_optimized(1524000, 13000, &m, &n);
|
|
get_m_n_optimized(1524000, 16800, &m, &n);
|
|
get_m_n_optimized(1524000, 19200, &m, &n);
|
|
get_m_n_optimized(1524000, 26000, &m, &n);
|
|
get_m_n_optimized(1524000, 27000, &m, &n);
|
|
|
|
/* exact recommendation for SDPs */
|
|
get_m_n_optimized(1523712, 38400, &m, &n);
|
|
|
|
}
|