57 lines · c
1// SPDX-License-Identifier: GPL-2.0+2/*3 * Copyright (C) 2023 Loongson Technology Corporation Limited4 */5 6#include "lsdc_drv.h"7#include "lsdc_probe.h"8 9/*10 * Processor ID (implementation) values for bits 15:8 of the PRID register.11 */12#define LOONGSON_CPU_IMP_MASK 0xff0013#define LOONGSON_CPU_IMP_SHIFT 814 15#define LOONGARCH_CPU_IMP_LS2K1000 0xa016#define LOONGARCH_CPU_IMP_LS2K2000 0xb017#define LOONGARCH_CPU_IMP_LS3A5000 0xc018 19#define LOONGSON_CPU_MIPS_IMP_LS2K 0x61 /* Loongson 2K Mips series SoC */20 21/*22 * Particular Revision values for bits 7:0 of the PRID register.23 */24#define LOONGSON_CPU_REV_MASK 0x00ff25 26#define LOONGARCH_CPUCFG_PRID_REG 0x027 28/*29 * We can achieve fine-grained control with the information about the host.30 */31 32unsigned int loongson_cpu_get_prid(u8 *imp, u8 *rev)33{34 unsigned int prid = 0;35 36#if defined(__loongarch__)37 __asm__ volatile("cpucfg %0, %1\n\t"38 : "=&r"(prid)39 : "r"(LOONGARCH_CPUCFG_PRID_REG)40 );41#endif42 43#if defined(__mips__)44 __asm__ volatile("mfc0\t%0, $15\n\t"45 : "=r" (prid)46 );47#endif48 49 if (imp)50 *imp = (prid & LOONGSON_CPU_IMP_MASK) >> LOONGSON_CPU_IMP_SHIFT;51 52 if (rev)53 *rev = prid & LOONGSON_CPU_REV_MASK;54 55 return prid;56}57