[PATCH 5.10 505/663] MIPS: Ingenic: Disable HPTLB for D0 XBurst CPUs too

From: Greg Kroah-Hartman
Date: Mon Mar 01 2021 - 19:38:49 EST


From: Paul Cercueil <paul@xxxxxxxxxxxxxxx>

commit a5360958a3cd1d876aae1f504ae014658513e1af upstream.

The JZ4760 has the HPTLB as well, but has a XBurst CPU with a D0 CPUID.

Disable the HPTLB for all XBurst CPUs with a D0 CPUID. In the case where
there is no HPTLB (e.g. for older SoCs), this won't have any side
effect.

Fixes: b02efeb05699 ("MIPS: Ingenic: Disable abandoned HPTLB function.")
Cc: <stable@xxxxxxxxxxxxxxx> # 5.4
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Reviewed-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@xxxxxxxxxxxxxx>
Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/mips/kernel/cpu-probe.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -1830,16 +1830,17 @@ static inline void cpu_probe_ingenic(str
*/
case PRID_COMP_INGENIC_D0:
c->isa_level &= ~MIPS_CPU_ISA_M32R2;
- break;
+ fallthrough;

/*
* The config0 register in the XBurst CPUs with a processor ID of
- * PRID_COMP_INGENIC_D1 has an abandoned huge page tlb mode, this
- * mode is not compatible with the MIPS standard, it will cause
- * tlbmiss and into an infinite loop (line 21 in the tlb-funcs.S)
- * when starting the init process. After chip reset, the default
- * is HPTLB mode, Write 0xa9000000 to cp0 register 5 sel 4 to
- * switch back to VTLB mode to prevent getting stuck.
+ * PRID_COMP_INGENIC_D0 or PRID_COMP_INGENIC_D1 has an abandoned
+ * huge page tlb mode, this mode is not compatible with the MIPS
+ * standard, it will cause tlbmiss and into an infinite loop
+ * (line 21 in the tlb-funcs.S) when starting the init process.
+ * After chip reset, the default is HPTLB mode, Write 0xa9000000
+ * to cp0 register 5 sel 4 to switch back to VTLB mode to prevent
+ * getting stuck.
*/
case PRID_COMP_INGENIC_D1:
write_c0_page_ctrl(XBURST_PAGECTRL_HPTLB_DIS);