| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * Copyright 2013, Michael (Ellerman|Neuling), IBM Corporation. |
| */ |
| |
| #include <asm/asm-offsets.h> |
| #include <asm/ppc_asm.h> |
| #include <asm/reg.h> |
| |
| #include "subcore.h" |
| |
| |
| _GLOBAL(split_core_secondary_loop) |
| /* |
| * r3 = u8 *state, used throughout the routine |
| * r4 = temp |
| * r5 = temp |
| * .. |
| * r12 = MSR |
| */ |
| mfmsr r12 |
| |
| /* Disable interrupts so SRR0/1 don't get trashed */ |
| li r4,0 |
| ori r4,r4,MSR_EE|MSR_SE|MSR_BE|MSR_RI |
| andc r4,r12,r4 |
| sync |
| mtmsrd r4 |
| |
| /* Switch to real mode and leave interrupts off */ |
| li r5, MSR_IR|MSR_DR |
| andc r5, r4, r5 |
| |
| LOAD_REG_ADDR(r4, real_mode) |
| |
| mtspr SPRN_SRR0,r4 |
| mtspr SPRN_SRR1,r5 |
| rfid |
| b . /* prevent speculative execution */ |
| |
| real_mode: |
| /* Grab values from unsplit SPRs */ |
| mfspr r6, SPRN_LDBAR |
| mfspr r7, SPRN_PMMAR |
| mfspr r8, SPRN_PMCR |
| mfspr r9, SPRN_RPR |
| mfspr r10, SPRN_SDR1 |
| |
| /* Order reading the SPRs vs telling the primary we are ready to split */ |
| sync |
| |
| /* Tell thread 0 we are in real mode */ |
| li r4, SYNC_STEP_REAL_MODE |
| stb r4, 0(r3) |
| |
| li r5, (HID0_POWER8_4LPARMODE | HID0_POWER8_2LPARMODE)@highest |
| sldi r5, r5, 48 |
| |
| /* Loop until we see the split happen in HID0 */ |
| 1: mfspr r4, SPRN_HID0 |
| and. r4, r4, r5 |
| beq 1b |
| |
| /* |
| * We only need to initialise the below regs once for each subcore, |
| * but it's simpler and harmless to do it on each thread. |
| */ |
| |
| /* Make sure various SPRS have sane values */ |
| li r4, 0 |
| mtspr SPRN_LPID, r4 |
| mtspr SPRN_PCR, r4 |
| mtspr SPRN_HDEC, r4 |
| |
| /* Restore SPR values now we are split */ |
| mtspr SPRN_LDBAR, r6 |
| mtspr SPRN_PMMAR, r7 |
| mtspr SPRN_PMCR, r8 |
| mtspr SPRN_RPR, r9 |
| mtspr SPRN_SDR1, r10 |
| |
| LOAD_REG_ADDR(r5, virtual_mode) |
| |
| /* Get out of real mode */ |
| mtspr SPRN_SRR0,r5 |
| mtspr SPRN_SRR1,r12 |
| rfid |
| b . /* prevent speculative execution */ |
| |
| virtual_mode: |
| blr |
