合宙开发团队10月11日的提交中开源了AIR32F103的PLL倍频调节的代码, 使得在 Linux 下通过 GCC Arm 工具链也能编译运行216MHz.
示例代码位于 Examples/NonFreeRTOS/RCC 下: https://gitee.com/iosetting/air32f103-template/tree/master/Examples/NonFreeRTOS/RCC
编译时需要注意避免编译器对AIR_RCC_PLLConfig()
这个函数的优化.
这个函数的源代码如下, 可以看到其中会对特定地址(例如 0x40016C00)进行连续的写操作, 编译时如果优化参数不是**-O0**, 就大概率会将这些写操作合并或调换位置.
uint32_t AIR_RCC_PLLConfig(uint32_t RCC_PLLSource, uint32_t RCC_PLLMul, uint8_t Latency)
{
uint32_t sramsize = 0;
uint32_t pllmul = 0;
FunctionalState pwr_gating_state = 0;
/* Check the parameters */
assert_param(IS_RCC_PLL_SOURCE(RCC_PLLSource));
assert_param(IS_RCC_PLL_MUL(RCC_PLLMul));
*(uint32_t *)(0x400210F0) = BIT(0);//开启sys_cfg门控
*(uint32_t *)(0x40016C00) = 0xa7d93a86;//解一、二、三级锁
*(uint32_t *)(0x40016C00) = 0xab12dfcd;
*(uint32_t *)(0x40016C00) = 0xcded3526;
sramsize = *(uint32_t *)(0x40016C18);
*(uint32_t *)(0x40016C18) = 0x200183FF;//配置sram大小, 将BOOT使用对sram打开
*(uint32_t *)(0x4002228C) = 0xa5a5a5a5;//QSPI解锁
SysFreq_Set(RCC_PLLMul,Latency ,0,1);
RCC->CFGR = (RCC->CFGR & ~0x00030000) | RCC_PLLSource;
//恢复配置前状态
*(uint32_t *)(0x40016C18) = sramsize;
*(uint32_t *)(0x400210F0) = 0;//开启sys_cfg门控
*(uint32_t *)(0x40016C00) = ~0xa7d93a86;//加一、二、三级锁
*(uint32_t *)(0x40016C00) = ~0xab12dfcd;
*(uint32_t *)(0x40016C00) = ~0xcded3526;
*(uint32_t *)(0x4002228C) = ~0xa5a5a5a5;//QSPI解锁
return 1;
}
解决的方法一, 是通过调整编译参数
__NOP();
), 还可以通过int foo(int i) __attribute__((optimize("-O3")));
这样的形式, 参考GNU GCC文档因此将库函数修改为
__attribute__((optimize("-O0"))) uint32_t AIR_RCC_PLLConfig(uint32_t RCC_PLLSource, uint32_t RCC_PLLMul, uint8_t Latency)
示例中的 CoreMark_256MHz 项目, 可以将AIR32F103运行在最高256MHz主频下, 运行CoreMark性能测试. 以下是分别在 256MHz, 216MHz, 72MHz 不同编译器版本下的测试结果.
SYSCLK: 256000000, HCLK: 256000000, PCLK1: 128000000, PCLK2: 256000000, ADCCLK: 128000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 17054␊
Total time (secs): 17.054000␊
Iterations/Sec : 586.372698␊
Iterations : 10000␊
Compiler version : GCC11.2.1 20220111␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 586.372698 / GCC11.2.1 20220111 -O3 / STACK␊
IR32F103 CoreMark␊
SYSCLK: 256000000, HCLK: 256000000, PCLK1: 128000000, PCLK2: 256000000, ADCCLK: 128000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 17054␊
Total time (secs): 17.054000␊
Iterations/Sec : 586.372698␊
Iterations : 10000␊
Compiler version : GCC11.3.1 20220712␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 586.372698 / GCC11.3.1 20220712 -O3 / STACK␊
SYSCLK: 256000000, HCLK: 256000000, PCLK1: 128000000, PCLK2: 256000000, ADCCLK: 128000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 15822␊
Total time (secs): 15.822000␊
Iterations/Sec : 632.031349␊
Iterations : 10000␊
Compiler version : GCC12.2.0␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 632.031349 / GCC12.2.0 -O3 / STACK␊
SYSCLK: 216000000, HCLK: 216000000, PCLK1: 108000000, PCLK2: 216000000, ADCCLK: 108000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 20213␊
Total time (secs): 20.213000␊
Iterations/Sec : 494.731114␊
Iterations : 10000␊
Compiler version : GCC11.2.1 20220111␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 494.731114 / GCC11.2.1 20220111 -O3 / STACK␊
SYSCLK: 216000000, HCLK: 216000000, PCLK1: 108000000, PCLK2: 216000000, ADCCLK: 108000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 20213␊
Total time (secs): 20.213000␊
Iterations/Sec : 494.731114␊
Iterations : 10000␊
Compiler version : GCC11.3.1 20220712␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 494.731114 / GCC11.3.1 20220712 -O3 / STACK␊
SYSCLK: 216000000, HCLK: 216000000, PCLK1: 108000000, PCLK2: 216000000, ADCCLK: 108000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 18753␊
Total time (secs): 18.753000␊
Iterations/Sec : 533.248014␊
Iterations : 10000␊
Compiler version : GCC12.2.0␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 533.248014 / GCC12.2.0 -O3 / STACK␊
SYSCLK: 216.0Mhz, HCLK: 216.0Mhz, PCLK1: 108.0Mhz, PCLK2: 216.0Mhz, ADCCLK: 108.0Mhz
2K performance run parameters for coremark.
CoreMark Size : 666
Total ticks : 16328
Total time (secs): 16.328000
Iterations/Sec : 612.444880
Iterations : 10000
Compiler version : GCCClang 15.0.0
Compiler flags : -O3
Memory location : STACK
seedcrc : 0xe9f5
[0]crclist : 0xe714
[0]crcmatrix : 0x1fd7
[0]crcstate : 0x8e3a
[0]crcfinal : 0x988c
Correct operation validated. See readme.txt for run and reporting rules.
CoreMark 1.0 : 612.444880 / GCCClang 15.0.0 -O3 / STACK
SYSCLK: 72000000, HCLK: 72000000, PCLK1: 36000000, PCLK2: 72000000, ADCCLK: 36000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 60677␊
Total time (secs): 60.677000␊
Iterations/Sec : 164.807093␊
Iterations : 10000␊
Compiler version : GCC11.2.1 20220111␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 164.807093 / GCC11.2.1 20220111 -O3 / STACK␊
SYSCLK: 72000000, HCLK: 72000000, PCLK1: 36000000, PCLK2: 72000000, ADCCLK: 36000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 60677␊
Total time (secs): 60.677000␊
Iterations/Sec : 164.807093␊
Iterations : 10000␊
Compiler version : GCC11.3.1 20220712␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 164.807093 / GCC11.3.1 20220712 -O3 / STACK␊
SYSCLK: 72000000, HCLK: 72000000, PCLK1: 36000000, PCLK2: 72000000, ADCCLK: 36000000␊
2K performance run parameters for coremark.␊
CoreMark Size : 666␊
Total ticks : 56293␊
Total time (secs): 56.293000␊
Iterations/Sec : 177.641980␊
Iterations : 10000␊
Compiler version : GCC12.2.0␊
Compiler flags : -O3␊
Memory location : STACK␊
seedcrc : 0xe9f5␊
[0]crclist : 0xe714␊
[0]crcmatrix : 0x1fd7␊
[0]crcstate : 0x8e3a␊
[0]crcfinal : 0x988c␊
Correct operation validated. See readme.txt for run and reporting rules.␊
CoreMark 1.0 : 177.641980 / GCC12.2.0 -O3 / STACK␊
可以看到, GCC11.2和GCC11.3是一样的, GCC12.2生成的二进制执行性能提升了接近8%, 但是性能最好的还是AC6, 比GCC12.2性能高了接近15%.