// SPDX-License-Identifier: GPL-2.0
#include <linux/smp.h>
#include <linux/types.h>
#include <asm/cpu.h>
#include <asm/cpu-info.h>
#include <asm/elf.h>
#include <loongson_regs.h>
#include <cpucfg-emul.h>
static bool is_loongson(struct cpuinfo_mips *c)
{
switch (c->processor_id & PRID_COMP_MASK) {
case PRID_COMP_LEGACY:
return ((c->processor_id & PRID_IMP_MASK) ==
PRID_IMP_LOONGSON_64C);
case PRID_COMP_LOONGSON:
return true;
default:
return false;
}
}
static u32 get_loongson_fprev(struct cpuinfo_mips *c)
{
return c->fpu_id & LOONGSON_FPREV_MASK;
}
static bool cpu_has_uca(void)
{
u32 diag = read_c0_diag();
u32 new_diag;
if (diag & LOONGSON_DIAG_UCAC)
/* UCA is already enabled. */
return true;
/* See if UCAC bit can be flipped on. This should be safe. */
new_diag = diag | LOONGSON_DIAG_UCAC;
write_c0_diag(new_diag);
new_diag = read_c0_diag();
write_c0_diag(diag);
return (new_diag & LOONGSON_DIAG_UCAC) != 0;
}
static void probe_uca(struct cpuinfo_mips *c)
{
if (cpu_has_uca())
c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_LSUCA;
}
static void decode_loongson_config6(struct cpuinfo_mips *c)
{
u32 config6 = read_c0_config6();
if (config6 & LOONGSON_CONF6_SFBEN)
c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_SFBP;
if (config6 & LOONGSON_CONF6_LLEXC)
c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_LLEXC;
if (config6 & LOONGSON_CONF6_SCRAND)
c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_SCRAND;
}
static void patch_cpucfg_sel1(struct cpuinfo_mips *c)
{
u64 ases = c->ases;
u64 options = c->options;
u32 data = c->loongson3_cpucfg_data[0];
if (options & MIPS_CPU_FPU) {
data |= LOONGSON_CFG1_FP;
data |= get_loongson_fprev(c) << LOONGSON_CFG1_FPREV_OFFSET;
}
if (ases & MIPS_ASE_LOONGSON_MMI)
data |= LOONGSON_CFG1_MMI;
if (ases & MIPS_ASE_MSA)
data |= LOONGSON_CFG1_MSA1;
c->loongson3_cpucfg_data[0] = data;
}
static void patch_cpucfg_sel2(struct cpuinfo_mips *c)
{
u64 ases = c->ases;
u64 options = c->options;
u32 data = c->loongson3_cpucfg_data[1];
if (ases & MIPS_ASE_LOONGSON_EXT)
data |= LOONGSON_CFG2_LEXT1;
if (ases & MIPS_ASE_LOONGSON_EXT2)
data |= LOONGSON_CFG2_LEXT2;
if (options & MIPS_CPU_LDPTE)
data |= LOONGSON_CFG2_LSPW;
if (ases & MIPS_ASE_VZ)
data |= LOONGSON_CFG2_LVZP;
else
data &= ~LOONGSON_CFG2_LVZREV;
c->loongson3_cpucfg_data[1] = data;
}
static void patch_cpucfg_sel3(struct cpuinfo_mips *c)
{
u64 ases = c->ases;
u32 data = c->loongson3_cpucfg_data[2];
if (ases & MIPS_ASE_LOONGSON_CAM) {
data |= LOONGSON_CFG3_LCAMP;
} else {
data &= ~LOONGSON_CFG3_LCAMREV;
data &= ~LOONGSON_CFG3_LCAMNUM;
data &= ~LOONGSON_CFG3_LCAMKW;
data &= ~LOONGSON_CFG3_LCAMVW;
}
c->loongson3_cpucfg_data[2] = data;
}
void loongson3_cpucfg_synthesize_data(struct cpuinfo_mips *c)
{
/* Only engage the logic on Loongson processors. */
if (!is_loongson(c))
return;
/* CPUs with CPUCFG support don't need to synthesize anything. */
if (cpu_has_cfg())
goto have_cpucfg_now;
c->loongson3_cpucfg_data[0] = 0;
c->loongson3_cpucfg_data[1] = 0;
c->loongson3_cpucfg_data[2] = 0;
/* Add CPUCFG features non-discoverable otherwise. */
switch (c->processor_id & (PRID_IMP_MASK | PRID_REV_MASK)) {
case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_0:
case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_1:
case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_2:
case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_3:
decode_loongson_config6(c);
probe_uca(c);
c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_LSLDR0 |
LOONGSON_CFG1_LSSYNCI | LOONGSON_CFG1_LLSYNC |
LOONGSON_CFG1_TGTSYNC);
c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
LOONGSON_CFG2_LBT2 | LOONGSON_CFG2_LPMP |
LOONGSON_CFG2_LPM_REV2);
c->loongson3_cpucfg_data[2] = 0;
break;
case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R1:
c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_LSLDR0 |
LOONGSON_CFG1_LSSYNCI | LOONGSON_CFG1_LSUCA |
LOONGSON_CFG1_LLSYNC | LOONGSON_CFG1_TGTSYNC);
c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
LOONGSON_CFG2_LPMP | LOONGSON_CFG2_LPM_REV1);
c->loongson3_cpucfg_data[2] |= (
LOONGSON_CFG3_LCAM_REV1 |
LOONGSON_CFG3_LCAMNUM_REV1 |
LOONGSON_CFG3_LCAMKW_REV1 |
LOONGSON_CFG3_LCAMVW_REV1);
break;
case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3B_R1:
case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3B_R2:
c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_LSLDR0 |
LOONGSON_CFG1_LSSYNCI | LOONGSON_CFG1_LSUCA |
LOONGSON_CFG1_LLSYNC | LOONGSON_CFG1_TGTSYNC);
c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
LOONGSON_CFG2_LPMP | LOONGSON_CFG2_LPM_REV1);
c->loongson3_cpucfg_data[2] |= (
LOONGSON_CFG3_LCAM_REV1 |
LOONGSON_CFG3_LCAMNUM_REV1 |
LOONGSON_CFG3_LCAMKW_REV1 |
LOONGSON_CFG3_LCAMVW_REV1);
break;
case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R2_0:
case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R2_1:
case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R3_0:
case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R3_1:
decode_loongson_config6(c);
probe_uca(c);
c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_CNT64 |
LOONGSON_CFG1_LSLDR0 | LOONGSON_CFG1_LSPREF |
LOONGSON_CFG1_LSPREFX | LOONGSON_CFG1_LSSYNCI |
LOONGSON_CFG1_LLSYNC | LOONGSON_CFG1_TGTSYNC);
c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
LOONGSON_CFG2_LBT2 | LOONGSON_CFG2_LBTMMU |
LOONGSON_CFG2_LPMP | LOONGSON_CFG2_LPM_REV1 |
LOONGSON_CFG2_LVZ_REV1);
c->loongson3_cpucfg_data[2] |= (LOONGSON_CFG3_LCAM_REV1 |
LOONGSON_CFG3_LCAMNUM_REV1 |
LOONGSON_CFG3_LCAMKW_REV1 |
LOONGSON_CFG3_LCAMVW_REV1);
break;
default:
/* It is possible that some future Loongson cores still do
* not have CPUCFG, so do not emulate anything for these
* cores.
*/
return;
}
/* This feature is set by firmware, but all known Loongson-64 systems
* are configured this way.
*/
c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_CDMAP;
/* Patch in dynamically probed bits. */
patch_cpucfg_sel1(c);
patch_cpucfg_sel2(c);
patch_cpucfg_sel3(c);
have_cpucfg_now:
/* We have usable CPUCFG now, emulated or not.
* Announce CPUCFG availability to userspace via hwcap.
*/
elf_hwcap |= HWCAP_LOONGSON_CPUCFG;
}
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