Re: [PATCH 02/11] MIPS: use virtual addresses from xkphys for MIPS64

From: Gregory CLEMENT
Date: Mon Oct 23 2023 - 11:45:43 EST


Hello Jiaxun,

> 在2023年10月4日十月 下午5:10,Gregory CLEMENT写道:
>> From: Vladimir Kondratiev <vladimir.kondratiev@xxxxxxxxx>
>>
>> Now 64-bit MIPS uses 32-bit compatible segments KSEG0 and KSEG1
>> to trivially map first 1/2 GByte of physical memory. This memory
>> used to run kernel. This mean, one should have memory installed
>> in this area in order for Linux to work.
>>
>> Kconfig CONFIG_USE_XKPHYS introduced; it adds support for kernel
>> to use virtual addresses from the XKPHYS segment for both cached
>> and uncached access. XKPHYS allows to access 2^48 bytes of
>> memory, thus allowing kernel to work with any memory
>> configuration.
>>
>> MIPS CPU sets KX bit in the CP0 status register at reset
>> if RESET_BASE_MODE (BIT 1) set in the GCR_CL_RESET_BASE.
>>
>> Reset vector should fit into 32-bit. If reset vector put outside of
>> KSEG1, BIT(1) should be set in this value.
>>
>> IRQ handler for CPU updated to generate 64-bit address for jump
>
> Please use existing KBUILD_SYM32 symbol.

Could you add more detail ?

Where do you think KBUILD_SYM32 symbol should be used ?

Gregory


>
> Thanks
> - Jiaxun
>
>>
>> Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@xxxxxxxxx>
>> Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
>> ---
>> arch/mips/Kconfig | 15 +++++++++++++
>> arch/mips/Makefile | 4 ++++
>> arch/mips/generic/Platform | 5 +++++
>> arch/mips/include/asm/addrspace.h | 12 ++++++++--
>> arch/mips/include/asm/mips-cm.h | 1 +
>> arch/mips/include/asm/page.h | 10 +++++++++
>> arch/mips/include/asm/vga.h | 4 ++++
>> arch/mips/kernel/cps-vec.S | 8 +++++++
>> arch/mips/kernel/genex.S | 14 ++++++++++++
>> arch/mips/kernel/smp-cps.c | 37 +++++++++++++++++++++++--------
>> arch/mips/kernel/traps.c | 32 +++++++++++++++++++++++---
>> arch/mips/lib/uncached.c | 10 +++++++++
>> arch/mips/mm/init.c | 4 ++--
>> 13 files changed, 140 insertions(+), 16 deletions(-)
>>
>> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
>> index bc8421859006..92832bbcca5d 100644
>> --- a/arch/mips/Kconfig
>> +++ b/arch/mips/Kconfig
>> @@ -2026,6 +2026,21 @@ config 64BIT
>>
>> endchoice
>>
>> +config USE_XKPHYS
>> + bool "use virtual address from XKPHYS"
>> + depends on 64BIT
>> + default n
>> + help
>> + By default, MIPS uses 32-bit compatible segments KSEG0 and KSEG1
>> + to trivially map first 1/2 GByte of physical memory. This mean,
>> + one should have memory installed in this area in order for Linux to
>> + work. With this option selected, kernel uses virtual addresses from
>> + the XKPHYS segment for both cached and uncached access. XKPHYS allows
>> + to access 2^48 bytes of memory, thus allowing to work with any memory
>> + configuration.
>> +
>> + Say N if not sure
>> +
>> config MIPS_VA_BITS_48
>> bool "48 bits virtual memory"
>> depends on 64BIT
>> diff --git a/arch/mips/Makefile b/arch/mips/Makefile
>> index f49807e1f19b..544ee8427cab 100644
>> --- a/arch/mips/Makefile
>> +++ b/arch/mips/Makefile
>> @@ -303,6 +303,10 @@ ifdef CONFIG_64BIT
>> endif
>> endif
>>
>> + ifdef CONFIG_USE_XKPHYS
>> + KBUILD_SYM32 = n
>> + endif
>> +
>> ifeq ($(KBUILD_SYM32), y)
>> cflags-$(KBUILD_SYM32) += -msym32 -DKBUILD_64BIT_SYM32
>> else
>> diff --git a/arch/mips/generic/Platform b/arch/mips/generic/Platform
>> index 0c03623f3897..2be9947814ad 100644
>> --- a/arch/mips/generic/Platform
>> +++ b/arch/mips/generic/Platform
>> @@ -12,7 +12,12 @@
>> cflags-$(CONFIG_MACH_INGENIC_SOC) +=
>> -I$(srctree)/arch/mips/include/asm/mach-ingenic
>> cflags-$(CONFIG_MIPS_GENERIC) +=
>> -I$(srctree)/arch/mips/include/asm/mach-generic
>>
>> +ifndef (CONFIG_USE_XKPHYS)
>> load-$(CONFIG_MIPS_GENERIC) += 0xffffffff80100000
>> +else
>> +load-$(CONFIG_MIPS_GENERIC) += 0xa800000080100000
>> +endif
>> +
>> all-$(CONFIG_MIPS_GENERIC) += vmlinux.gz.itb
>>
>> its-y := vmlinux.its.S
>> diff --git a/arch/mips/include/asm/addrspace.h
>> b/arch/mips/include/asm/addrspace.h
>> index 59a48c60a065..8dc500d8e66d 100644
>> --- a/arch/mips/include/asm/addrspace.h
>> +++ b/arch/mips/include/asm/addrspace.h
>> @@ -65,10 +65,15 @@
>> #define XKSSEG _CONST64_(0x4000000000000000)
>> #define XKPHYS _CONST64_(0x8000000000000000)
>> #define XKSEG _CONST64_(0xc000000000000000)
>> +#if !defined(CONFIG_USE_XKPHYS)
>> #define CKSEG0 _CONST64_(0xffffffff80000000)
>> #define CKSEG1 _CONST64_(0xffffffffa0000000)
>> #define CKSSEG _CONST64_(0xffffffffc0000000)
>> #define CKSEG3 _CONST64_(0xffffffffe0000000)
>> +#else
>> +#define CKSEG0 XKPHYS_CM_CACHED
>> +#define CKSEG1 XKPHYS_CM_UNCACHED
>> +#endif /* !defined(CONFIG_USE_XKPHYS) */
>>
>> #define CKSEG0ADDR(a) (CPHYSADDR(a) | CKSEG0)
>> #define CKSEG1ADDR(a) (CPHYSADDR(a) | CKSEG1)
>> @@ -126,8 +131,11 @@
>> #define PHYS_TO_XKSEG_UNCACHED(p) PHYS_TO_XKPHYS(K_CALG_UNCACHED, (p))
>> #define PHYS_TO_XKSEG_CACHED(p) PHYS_TO_XKPHYS(K_CALG_COH_SHAREABLE, (p))
>> #define XKPHYS_TO_PHYS(p) ((p) & TO_PHYS_MASK)
>> -#define PHYS_TO_XKPHYS(cm, a) (XKPHYS | (_ACAST64_(cm) << 59) | (a))
>> -
>> +#define XKPHYS_CM(cm) (XKPHYS | (_ACAST64_(cm) << 59))
>> +#define PHYS_TO_XKPHYS(cm, a) (XKPHYS_CM(cm) | (a))
>> +#define XKPHYS_CM_CACHED (XKPHYS_CM(K_CALG_COH_SHAREABLE))
>> +#define XKPHYS_CM_UNCACHED (XKPHYS_CM(K_CALG_UNCACHED))
>> +#define IS_XKPHYS(a) (((a) >> 62) == 2)
>> /*
>> * The ultimate limited of the 64-bit MIPS architecture: 2 bits for selecting
>> * the region, 3 bits for the CCA mode. This leaves 59 bits of which the
>> diff --git a/arch/mips/include/asm/mips-cm.h b/arch/mips/include/asm/mips-cm.h
>> index 23c67c0871b1..15d8d69de455 100644
>> --- a/arch/mips/include/asm/mips-cm.h
>> +++ b/arch/mips/include/asm/mips-cm.h
>> @@ -311,6 +311,7 @@ GCR_CX_ACCESSOR_RW(32, 0x018, other)
>> /* GCR_Cx_RESET_BASE - Configure where powered up cores will fetch from */
>> GCR_CX_ACCESSOR_RW(32, 0x020, reset_base)
>> #define CM_GCR_Cx_RESET_BASE_BEVEXCBASE GENMASK(31, 12)
>> +#define CM_GCR_Cx_RESET_BASE_MODE BIT(1)
>>
>> /* GCR_Cx_ID - Identify the current core */
>> GCR_CX_ACCESSOR_RO(32, 0x028, id)
>> diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
>> index 5978a8dfb917..53b8306da571 100644
>> --- a/arch/mips/include/asm/page.h
>> +++ b/arch/mips/include/asm/page.h
>> @@ -176,7 +176,11 @@ static inline unsigned long ___pa(unsigned long x)
>> * the compatibility segements ckseg0 or ckseg1, or it may
>> * be in xkphys.
>> */
>> +#if defined(CONFIG_USE_XKPHYS)
>> + return XPHYSADDR(x);
>> +#else
>> return x < CKSEG0 ? XPHYSADDR(x) : CPHYSADDR(x);
>> +#endif
>> }
>>
>> if (!IS_ENABLED(CONFIG_EVA)) {
>> @@ -196,7 +200,11 @@ static inline unsigned long ___pa(unsigned long x)
>> return x - PAGE_OFFSET + PHYS_OFFSET;
>> }
>> #define __pa(x) ___pa((unsigned long)(x))
>> +#if IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_USE_XKPHYS)
>> +#define __va(x) ((void *)PHYS_TO_XKSEG_CACHED(x))
>> +#else
>> #define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
>> +#endif
>> #include <asm/io.h>
>>
>> /*
>> @@ -239,6 +247,8 @@ static inline unsigned long kaslr_offset(void)
>> return __kaslr_offset;
>> }
>>
>> +#define UNCAC_ADDR(addr) (UNCAC_BASE + __pa(addr))
>> +
>> #include <asm-generic/memory_model.h>
>> #include <asm-generic/getorder.h>
>>
>> diff --git a/arch/mips/include/asm/vga.h b/arch/mips/include/asm/vga.h
>> index 0136e0366698..e338e57d0784 100644
>> --- a/arch/mips/include/asm/vga.h
>> +++ b/arch/mips/include/asm/vga.h
>> @@ -16,7 +16,11 @@
>> * access the videoram directly without any black magic.
>> */
>>
>> +#if defined(CONFIG_USE_XKPHYS)
>> +#define VGA_MAP_MEM(x, s) UNCAC_ADDR(0x10000000L + (unsigned long)(x))
>> +#else
>> #define VGA_MAP_MEM(x, s) CKSEG1ADDR(0x10000000L + (unsigned long)(x))
>> +#endif
>>
>> #define vga_readb(x) (*(x))
>> #define vga_writeb(x, y) (*(y) = (x))
>> diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S
>> index 64ecfdac6580..541f31a43a7f 100644
>> --- a/arch/mips/kernel/cps-vec.S
>> +++ b/arch/mips/kernel/cps-vec.S
>> @@ -554,7 +554,11 @@ LEAF(mips_cps_cache_init)
>> mul t1, t1, t0
>> mul t1, t1, t2
>>
>> +#if defined(CONFIG_USE_XKPHYS)
>> + PTR_LI a0, XKPHYS_CM_CACHED
>> +#else
>> li a0, CKSEG0
>> +#endif
>> PTR_ADD a1, a0, t1
>> 1: cache Index_Store_Tag_I, 0(a0)
>> PTR_ADD a0, a0, t0
>> @@ -581,7 +585,11 @@ icache_done:
>> mul t1, t1, t0
>> mul t1, t1, t2
>>
>> +#if defined(CONFIG_USE_XKPHYS)
>> + PTR_LI a0, XKPHYS_CM_CACHED
>> +#else
>> li a0, CKSEG0
>> +#endif
>> PTR_ADDU a1, a0, t1
>> PTR_SUBU a1, a1, t0
>> 1: cache Index_Store_Tag_D, 0(a0)
>> diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
>> index b6de8e88c1bd..a002058e1838 100644
>> --- a/arch/mips/kernel/genex.S
>> +++ b/arch/mips/kernel/genex.S
>> @@ -272,11 +272,25 @@ NESTED(except_vec_vi, 0, sp)
>> .set push
>> .set noreorder
>> PTR_LA v1, except_vec_vi_handler
>> +#if defined(CONFIG_USE_XKPHYS)
>> +FEXPORT(except_vec_vi_63_48)
>> + lui v0, 0 /* Patched - bits 63:48 */
>> +FEXPORT(except_vec_vi_47_32)
>> + ori v0, 0 /* Patched - bits 47:32 */
>> + dsll v0, v0, 0x10
>> +FEXPORT(except_vec_vi_31_16)
>> + ori v0, 0 /* Patched - bits 31:16 */
>> + dsll v0, v0, 0x10
>> + jr v1
>> +FEXPORT(except_vec_vi_15_0)
>> + ori v0, 0 /* Patched - bits 15:0 */
>> +#else /* defined(CONFIG_USE_XKPHYS) */
>> FEXPORT(except_vec_vi_lui)
>> lui v0, 0 /* Patched */
>> jr v1
>> FEXPORT(except_vec_vi_ori)
>> ori v0, 0 /* Patched */
>> +#endif /* defined(CONFIG_USE_XKPHYS) */
>> .set pop
>> END(except_vec_vi)
>> EXPORT(except_vec_vi_end)
>> diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c
>> index dd55d59b88db..47e76722a306 100644
>> --- a/arch/mips/kernel/smp-cps.c
>> +++ b/arch/mips/kernel/smp-cps.c
>> @@ -34,10 +34,33 @@ static unsigned __init core_vpe_count(unsigned int
>> cluster, unsigned core)
>> return min(smp_max_threads, mips_cps_numvps(cluster, core));
>> }
>>
>> +/**
>> + * plat_core_entry - query reset vector for NMI/reset
>> + *
>> + * Returns low 32 bits of the reset vector
>> + *
>> + * This is used to fill 2 registers:
>> + * - BEV Base (GCR_BEV_BASE) Offset: 0x0680
>> + * - VP Local Reset Exception Base (GCR_CL_RESET_BASE,GCR_CO_RESET_BASE)
>> + * Offset: 0x0020 (0x2020 relative to GCR_BASE_ADDR)
>> + *
>> + * In both registers, BIT(1) should be set in case it uses address in XKPHYS
>> + * (as opposed to KSEG1). This bit defined as CM_GCR_Cx_RESET_BASE_MODE,
>> + * using it unconditionally because for GCR_BEV_BASE its value is the same
>> + */
>> +static u32 plat_core_entry(void)
>> +{
>> +#if defined(CONFIG_USE_XKPHYS)
>> + return (UNCAC_ADDR(mips_cps_core_entry) & 0xffffffff)
>> + | CM_GCR_Cx_RESET_BASE_MODE;
>> +#else
>> + return CKSEG1ADDR((unsigned long)mips_cps_core_entry);
>> +#endif
>> +}
>> +
>> static void __init cps_smp_setup(void)
>> {
>> unsigned int nclusters, ncores, nvpes, core_vpes;
>> - unsigned long core_entry;
>> int cl, c, v;
>>
>> /* Detect & record VPE topology */
>> @@ -94,10 +117,8 @@ static void __init cps_smp_setup(void)
>> /* Make core 0 coherent with everything */
>> write_gcr_cl_coherence(0xff);
>>
>> - if (mips_cm_revision() >= CM_REV_CM3) {
>> - core_entry = CKSEG1ADDR((unsigned long)mips_cps_core_entry);
>> - write_gcr_bev_base(core_entry);
>> - }
>> + if (mips_cm_revision() >= CM_REV_CM3)
>> + write_gcr_bev_base(plat_core_entry());
>>
>> #ifdef CONFIG_MIPS_MT_FPAFF
>> /* If we have an FPU, enroll ourselves in the FPU-full mask */
>> @@ -213,7 +234,7 @@ static void boot_core(unsigned int core, unsigned
>> int vpe_id)
>> mips_cm_lock_other(0, core, 0, CM_GCR_Cx_OTHER_BLOCK_LOCAL);
>>
>> /* Set its reset vector */
>> - write_gcr_co_reset_base(CKSEG1ADDR((unsigned long)mips_cps_core_entry));
>> + write_gcr_co_reset_base(plat_core_entry());
>>
>> /* Ensure its coherency is disabled */
>> write_gcr_co_coherence(0);
>> @@ -290,7 +311,6 @@ static int cps_boot_secondary(int cpu, struct
>> task_struct *idle)
>> unsigned vpe_id = cpu_vpe_id(&cpu_data[cpu]);
>> struct core_boot_config *core_cfg = &mips_cps_core_bootcfg[core];
>> struct vpe_boot_config *vpe_cfg = &core_cfg->vpe_config[vpe_id];
>> - unsigned long core_entry;
>> unsigned int remote;
>> int err;
>>
>> @@ -314,8 +334,7 @@ static int cps_boot_secondary(int cpu, struct
>> task_struct *idle)
>>
>> if (cpu_has_vp) {
>> mips_cm_lock_other(0, core, vpe_id, CM_GCR_Cx_OTHER_BLOCK_LOCAL);
>> - core_entry = CKSEG1ADDR((unsigned long)mips_cps_core_entry);
>> - write_gcr_co_reset_base(core_entry);
>> + write_gcr_co_reset_base(plat_core_entry());
>> mips_cm_unlock_other();
>> }
>>
>> diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
>> index 246c6a6b0261..875594843626 100644
>> --- a/arch/mips/kernel/traps.c
>> +++ b/arch/mips/kernel/traps.c
>> @@ -2091,11 +2091,20 @@ static void *set_vi_srs_handler(int n,
>> vi_handler_t addr, int srs)
>> * If no shadow set is selected then use the default handler
>> * that does normal register saving and standard interrupt exit
>> */
>> - extern const u8 except_vec_vi[], except_vec_vi_lui[];
>> - extern const u8 except_vec_vi_ori[], except_vec_vi_end[];
>> + extern const u8 except_vec_vi[], except_vec_vi_end[];
>> extern const u8 rollback_except_vec_vi[];
>> const u8 *vec_start = using_rollback_handler() ?
>> rollback_except_vec_vi : except_vec_vi;
>> + const int handler_len = except_vec_vi_end - vec_start;
>> +#if defined(CONFIG_USE_XKPHYS)
>> + extern const u8 except_vec_vi_63_48[], except_vec_vi_47_32[];
>> + extern const u8 except_vec_vi_31_16[], except_vec_vi_15_0[];
>> + const int offset_63_48 = except_vec_vi_63_48 - vec_start;
>> + const int offset_47_32 = except_vec_vi_47_32 - vec_start;
>> + const int offset_31_16 = except_vec_vi_31_16 - vec_start;
>> + const int offset_15_0 = except_vec_vi_15_0 - vec_start;
>> +#else /* defined(CONFIG_USE_XKPHYS) */
>> + extern const u8 except_vec_vi_lui[], except_vec_vi_ori[];
>> #if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN)
>> const int lui_offset = except_vec_vi_lui - vec_start + 2;
>> const int ori_offset = except_vec_vi_ori - vec_start + 2;
>> @@ -2103,7 +2112,7 @@ static void *set_vi_srs_handler(int n,
>> vi_handler_t addr, int srs)
>> const int lui_offset = except_vec_vi_lui - vec_start;
>> const int ori_offset = except_vec_vi_ori - vec_start;
>> #endif
>> - const int handler_len = except_vec_vi_end - vec_start;
>> +#endif /* defined(CONFIG_USE_XKPHYS) */
>>
>> if (handler_len > VECTORSPACING) {
>> /*
>> @@ -2119,10 +2128,21 @@ static void *set_vi_srs_handler(int n,
>> vi_handler_t addr, int srs)
>> #else
>> handler_len);
>> #endif
>> +#if defined(CONFIG_USE_XKPHYS)
>> + h = (u16 *)(b + offset_63_48);
>> + *h = (handler >> 48) & 0xffff;
>> + h = (u16 *)(b + offset_47_32);
>> + *h = (handler >> 32) & 0xffff;
>> + h = (u16 *)(b + offset_31_16);
>> + *h = (handler >> 16) & 0xffff;
>> + h = (u16 *)(b + offset_15_0);
>> + *h = (handler >> 0) & 0xffff;
>> +#else /* defined(CONFIG_USE_XKPHYS) */
>> h = (u16 *)(b + lui_offset);
>> *h = (handler >> 16) & 0xffff;
>> h = (u16 *)(b + ori_offset);
>> *h = (handler & 0xffff);
>> +#endif /* defined(CONFIG_USE_XKPHYS) */
>> local_flush_icache_range((unsigned long)b,
>> (unsigned long)(b+handler_len));
>> }
>> @@ -2332,7 +2352,11 @@ static const char panic_null_cerr[] =
>> void set_uncached_handler(unsigned long offset, void *addr,
>> unsigned long size)
>> {
>> +#if IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_USE_XKPHYS)
>> + unsigned long uncached_ebase = UNCAC_ADDR(ebase);
>> +#else
>> unsigned long uncached_ebase = CKSEG1ADDR(ebase);
>> +#endif
>>
>> if (!addr)
>> panic(panic_null_cerr);
>> @@ -2384,9 +2408,11 @@ void __init trap_init(void)
>> * EVA is special though as it allows segments to be rearranged
>> * and to become uncached during cache error handling.
>> */
>> +#if !defined(CONFIG_USE_XKPHYS)
>> if (!IS_ENABLED(CONFIG_EVA) && !WARN_ON(ebase_pa >= 0x20000000))
>> ebase = CKSEG0ADDR(ebase_pa);
>> else
>> +#endif
>> ebase = (unsigned long)phys_to_virt(ebase_pa);
>> }
>>
>> diff --git a/arch/mips/lib/uncached.c b/arch/mips/lib/uncached.c
>> index f80a67c092b6..8a78348a2dd7 100644
>> --- a/arch/mips/lib/uncached.c
>> +++ b/arch/mips/lib/uncached.c
>> @@ -44,6 +44,10 @@ unsigned long run_uncached(void *func)
>>
>> __asm__("move %0, $sp" : "=r" (sp));
>>
>> +#if defined(CONFIG_USE_XKPHYS)
>> + if (IS_XKPHYS(sp))
>> + usp = UNCAC_ADDR(sp);
>> +#else /* defined(CONFIG_USE_XKPHYS) */
>> if (sp >= (long)CKSEG0 && sp < (long)CKSEG2)
>> usp = CKSEG1ADDR(sp);
>> #ifdef CONFIG_64BIT
>> @@ -52,10 +56,15 @@ unsigned long run_uncached(void *func)
>> usp = PHYS_TO_XKPHYS(K_CALG_UNCACHED,
>> XKPHYS_TO_PHYS((long long)sp));
>> #endif
>> +#endif /* defined(CONFIG_USE_XKPHYS) */
>> else {
>> BUG();
>> usp = sp;
>> }
>> +#if defined(CONFIG_USE_XKPHYS)
>> + if (IS_XKPHYS(lfunc))
>> + ufunc = UNCAC_ADDR(lfunc);
>> +#else /* defined(CONFIG_USE_XKPHYS) */
>> if (lfunc >= (long)CKSEG0 && lfunc < (long)CKSEG2)
>> ufunc = CKSEG1ADDR(lfunc);
>> #ifdef CONFIG_64BIT
>> @@ -64,6 +73,7 @@ unsigned long run_uncached(void *func)
>> ufunc = PHYS_TO_XKPHYS(K_CALG_UNCACHED,
>> XKPHYS_TO_PHYS((long long)lfunc));
>> #endif
>> +#endif /* defined(CONFIG_USE_XKPHYS) */
>> else {
>> BUG();
>> ufunc = lfunc;
>> diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
>> index 5dcb525a8995..eb57283ec4e0 100644
>> --- a/arch/mips/mm/init.c
>> +++ b/arch/mips/mm/init.c
>> @@ -427,7 +427,7 @@ void __init paging_init(void)
>> free_area_init(max_zone_pfns);
>> }
>>
>> -#ifdef CONFIG_64BIT
>> +#if defined(CONFIG_64BIT) && !defined(CONFIG_USE_XKPHYS)
>> static struct kcore_list kcore_kseg0;
>> #endif
>>
>> @@ -470,7 +470,7 @@ void __init mem_init(void)
>> setup_zero_pages(); /* Setup zeroed pages. */
>> mem_init_free_highmem();
>>
>> -#ifdef CONFIG_64BIT
>> +#if defined(CONFIG_64BIT) && !defined(CONFIG_USE_XKPHYS)
>> if ((unsigned long) &_text > (unsigned long) CKSEG0)
>> /* The -4 is a hack so that user tools don't have to handle
>> the overflow. */
>> --
>> 2.40.1
>
> --
> - Jiaxun

--
Gregory Clement, Bootlin
Embedded Linux and Kernel engineering
http://bootlin.com