[PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[yingjie_bai]

From: Bai Yingjie <byj.tea@gmail.com>

CPU like P4080 has 36bit physical address, its DDR physical
start address can be configured above 4G by LAW registers.

For such systems in which their physical memory start address was
configured higher than 4G, we need also to write addr_h into the spin
table of the target secondary CPU, so that addr_h and addr_l together
represent a 64bit physical address.
Otherwise the secondary core can not get correct entry to start from.

This should do no harm for normal case where addr_h is all 0.

Signed-off-by: Bai Yingjie <byj.tea@gmail.com>
---
 arch/powerpc/platforms/85xx/smp.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index 8c7ea2486bc0..f12cdd1e80ff 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -252,6 +252,14 @@ static int smp_85xx_start_cpu(int cpu)
 	out_be64((u64 *)(&spin_table->addr_h),
 		__pa(ppc_function_entry(generic_secondary_smp_init)));
 #else
+	/*
+	 * We need also to write addr_h to spin table for systems
+	 * in which their physical memory start address was configured
+	 * to above 4G, otherwise the secondary core can not get
+	 * correct entry to start from.
+	 * This does no harm for normal case where addr_h is all 0.
+	 */
+	out_be32(&spin_table->addr_h, __pa(__early_start) >> 32);
 	out_be32(&spin_table->addr_l, __pa(__early_start));
 #endif
 	flush_spin_table(spin_table);
-- 
2.17.1

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Scott Wood]

On Mon, 2019-11-25 at 23:15 +0800, yingjie_bai@126.com wrote:
> From: Bai Yingjie <byj.tea@gmail.com>
> 
> CPU like P4080 has 36bit physical address, its DDR physical
> start address can be configured above 4G by LAW registers.
> 
> For such systems in which their physical memory start address was
> configured higher than 4G, we need also to write addr_h into the spin
> table of the target secondary CPU, so that addr_h and addr_l together
> represent a 64bit physical address.
> Otherwise the secondary core can not get correct entry to start from.
> 
> This should do no harm for normal case where addr_h is all 0.
> 
> Signed-off-by: Bai Yingjie <byj.tea@gmail.com>
> ---
>  arch/powerpc/platforms/85xx/smp.c | 8 ++++++++
>  1 file changed, 8 insertions(+)

Acked-by: Scott Wood <oss@buserror.net>

-Scott

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Michael Ellerman]

yingjie_bai@126.com writes:
> From: Bai Yingjie <byj.tea@gmail.com>
>
> CPU like P4080 has 36bit physical address, its DDR physical
> start address can be configured above 4G by LAW registers.
>
> For such systems in which their physical memory start address was
> configured higher than 4G, we need also to write addr_h into the spin
> table of the target secondary CPU, so that addr_h and addr_l together
> represent a 64bit physical address.
> Otherwise the secondary core can not get correct entry to start from.
>
> This should do no harm for normal case where addr_h is all 0.
>
> Signed-off-by: Bai Yingjie <byj.tea@gmail.com>
> ---
>  arch/powerpc/platforms/85xx/smp.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
> index 8c7ea2486bc0..f12cdd1e80ff 100644
> --- a/arch/powerpc/platforms/85xx/smp.c
> +++ b/arch/powerpc/platforms/85xx/smp.c
> @@ -252,6 +252,14 @@ static int smp_85xx_start_cpu(int cpu)
>  	out_be64((u64 *)(&spin_table->addr_h),
>  		__pa(ppc_function_entry(generic_secondary_smp_init)));
>  #else
> +	/*
> +	 * We need also to write addr_h to spin table for systems
> +	 * in which their physical memory start address was configured
> +	 * to above 4G, otherwise the secondary core can not get
> +	 * correct entry to start from.
> +	 * This does no harm for normal case where addr_h is all 0.
> +	 */
> +	out_be32(&spin_table->addr_h, __pa(__early_start) >> 32);
>  	out_be32(&spin_table->addr_l, __pa(__early_start));

This breaks the corenet32_smp_defconfig build:

  /linux/arch/powerpc/platforms/85xx/smp.c: In function 'smp_85xx_start_cpu':
  /linux/arch/powerpc/platforms/85xx/smp.c:262:52: error: right shift count >= width of type [-Werror=shift-count-overflow]
    262 |  out_be32(&spin_table->addr_h, __pa(__early_start) >> 32);
        |                                                    ^~
  cc1: all warnings being treated as errors

cheers

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Yingjie Bai]

Hi Michael,
Thanks for pointing out the issue. My mistake...
This patch should indeed make sense only when
CONFIG_PHYS_64BIT=y

I could not find corenet32_smp_defconfig, but I guess in your config,
CONFIG_PHYS_64BIT=n ?
I will update the patch later today

On Sun, Dec 22, 2019 at 5:38 PM Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> yingjie_bai@126.com writes:
> > From: Bai Yingjie <byj.tea@gmail.com>
> >
> > CPU like P4080 has 36bit physical address, its DDR physical
> > start address can be configured above 4G by LAW registers.
> >
> > For such systems in which their physical memory start address was
> > configured higher than 4G, we need also to write addr_h into the spin
> > table of the target secondary CPU, so that addr_h and addr_l together
> > represent a 64bit physical address.
> > Otherwise the secondary core can not get correct entry to start from.
> >
> > This should do no harm for normal case where addr_h is all 0.
> >
> > Signed-off-by: Bai Yingjie <byj.tea@gmail.com>
> > ---
> >  arch/powerpc/platforms/85xx/smp.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> >
> > diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
> > index 8c7ea2486bc0..f12cdd1e80ff 100644
> > --- a/arch/powerpc/platforms/85xx/smp.c
> > +++ b/arch/powerpc/platforms/85xx/smp.c
> > @@ -252,6 +252,14 @@ static int smp_85xx_start_cpu(int cpu)
> >       out_be64((u64 *)(&spin_table->addr_h),
> >               __pa(ppc_function_entry(generic_secondary_smp_init)));
> >  #else
> > +     /*
> > +      * We need also to write addr_h to spin table for systems
> > +      * in which their physical memory start address was configured
> > +      * to above 4G, otherwise the secondary core can not get
> > +      * correct entry to start from.
> > +      * This does no harm for normal case where addr_h is all 0.
> > +      */
> > +     out_be32(&spin_table->addr_h, __pa(__early_start) >> 32);
> >       out_be32(&spin_table->addr_l, __pa(__early_start));
>
> This breaks the corenet32_smp_defconfig build:
>
>   /linux/arch/powerpc/platforms/85xx/smp.c: In function 'smp_85xx_start_cpu':
>   /linux/arch/powerpc/platforms/85xx/smp.c:262:52: error: right shift count >= width of type [-Werror=shift-count-overflow]
>     262 |  out_be32(&spin_table->addr_h, __pa(__early_start) >> 32);
>         |                                                    ^~
>   cc1: all warnings being treated as errors
>
> cheers

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Scott Wood]

On Tue, 2019-12-24 at 09:35 +0800, Yingjie Bai wrote:
> Hi Michael,
> Thanks for pointing out the issue. My mistake...
> This patch should indeed make sense only when
> CONFIG_PHYS_64BIT=y
> 
> I could not find corenet32_smp_defconfig, but I guess in your config,
> CONFIG_PHYS_64BIT=n ?
> I will update the patch later today

corenet32_smp_defconfig is a makefile rule that pulls in multiple config
fragments.  It has CONFIG_PHYS_64BIT=y, but __pa() returns an unsigned long
regardless (which obviously needs to be fixed if DDR starting beyond 4G is to
be supported).

What 32-bit config are you using where this actually builds?

-Scott

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Yingjie Bai]

Hi Scott,

__pa() returns 64bit in my setup.

in arch/powerpc/include/asm/page.h

#if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + VIRT_PHYS_OFFSET))
#define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET)
#else
#ifdef CONFIG_PPC64
...



/* See Description below for VIRT_PHYS_OFFSET */
#if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
#ifdef CONFIG_RELOCATABLE
#define VIRT_PHYS_OFFSET virt_phys_offset
#else
#define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
#endif
#endif

and VIRT_PHYS_OFFSET is a variable, virt_phys_offset, which is long long
in arch/powerpc/mm/init_32.c
#ifdef CONFIG_RELOCATABLE
/* Used in __va()/__pa() */
long long virt_phys_offset;
EXPORT_SYMBOL(virt_phys_offset);
#endif


my config has
CONFIG_RELOCATABLE=y
CONFIG_BOOKE=y
CONFIG_FSL_BOOKE=y
CONFIG_PPC_FSL_BOOK3E=y
CONFIG_PPC_BOOK3E_MMU=y
CONFIG_FSL_SOC_BOOKE=y
CONFIG_FSL_CORENET_RCPM=y
CONFIG_CORENET_GENERIC=y
CONFIG_VDSO32=y
CONFIG_PPC32=y
CONFIG_32BIT=y
CONFIG_ARCH_HAS_ILOG2_U32=y
CONFIG_INIT_ENV_ARG_LIMIT=32
# CONFIG_PPC64 is not set
CONFIG_PTE_64BIT=y
CONFIG_PHYS_64BIT=y
CONFIG_ARCH_PHYS_ADDR_T_64BIT=y
CONFIG_ARCH_DMA_ADDR_T_64BIT=y
# CONFIG_HAVE_64BIT_ALIGNED_ACCESS is not set
CONFIG_PHYS_ADDR_T_64BIT=y
CONFIG_PCI_BUS_ADDR_T_64BIT=y
CONFIG_XZ_DEC_IA64=y
CONFIG_GENERIC_ATOMIC64=y
# CONFIG_ATOMIC64_SELFTEST is not set
CONFIG_PRINT_STACK_DEPTH=64


Here is my .config taken from a customized kernel, version 4.9
#
# Automatically generated file; DO NOT EDIT.
# Linux/powerpc 4.9.79 Kernel Configuration
#
# CONFIG_PPC64 is not set

#
# Processor support
#
# CONFIG_PPC_BOOK3S_32 is not set
CONFIG_PPC_85xx=y
# CONFIG_PPC_8xx is not set
# CONFIG_40x is not set
# CONFIG_44x is not set
# CONFIG_E200 is not set
CONFIG_E500=y
CONFIG_PPC_E500MC=y
CONFIG_PPC_FPU=y
CONFIG_FSL_EMB_PERFMON=y
CONFIG_FSL_EMB_PERF_EVENT=y
CONFIG_FSL_EMB_PERF_EVENT_E500=y
CONFIG_BOOKE=y
CONFIG_FSL_BOOKE=y
CONFIG_PPC_FSL_BOOK3E=y
CONFIG_PTE_64BIT=y
CONFIG_PHYS_64BIT=y
CONFIG_PPC_MMU_NOHASH=y
CONFIG_PPC_BOOK3E_MMU=y
# CONFIG_PPC_MM_SLICES is not set
CONFIG_SMP=y
CONFIG_NR_CPUS=4
CONFIG_PPC_DOORBELL=y
CONFIG_VDSO32=y
CONFIG_CPU_BIG_ENDIAN=y
CONFIG_PPC32=y
CONFIG_32BIT=y
CONFIG_ARCH_PHYS_ADDR_T_64BIT=y
CONFIG_ARCH_DMA_ADDR_T_64BIT=y
CONFIG_MMU=y
# CONFIG_HAVE_SETUP_PER_CPU_AREA is not set
# CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK is not set
CONFIG_NR_IRQS=512
CONFIG_STACKTRACE_SUPPORT=y
CONFIG_TRACE_IRQFLAGS_SUPPORT=y
CONFIG_LOCKDEP_SUPPORT=y
CONFIG_RWSEM_XCHGADD_ALGORITHM=y
CONFIG_GENERIC_LOCKBREAK=y
CONFIG_ARCH_HAS_ILOG2_U32=y
CONFIG_GENERIC_HWEIGHT=y
CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK=y
CONFIG_PPC=y
# CONFIG_GENERIC_CSUM is not set
CONFIG_EARLY_PRINTK=y
CONFIG_PANIC_TIMEOUT=180
CONFIG_GENERIC_NVRAM=y
CONFIG_SCHED_OMIT_FRAME_POINTER=y
CONFIG_ARCH_MAY_HAVE_PC_FDC=y
CONFIG_PPC_UDBG_16550=y
CONFIG_GENERIC_TBSYNC=y
CONFIG_AUDIT_ARCH=y
CONFIG_GENERIC_BUG=y
# CONFIG_EPAPR_BOOT is not set
CONFIG_DEFAULT_UIMAGE=y
CONFIG_ARCH_HIBERNATION_POSSIBLE=y
# CONFIG_PPC_DCR_NATIVE is not set
# CONFIG_PPC_DCR_MMIO is not set
CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y
CONFIG_ARCH_SUPPORTS_UPROBES=y
CONFIG_PPC_ADV_DEBUG_REGS=y
CONFIG_PPC_ADV_DEBUG_IACS=2
CONFIG_PPC_ADV_DEBUG_DACS=2
CONFIG_PPC_ADV_DEBUG_DVCS=0
CONFIG_PPC_ADV_DEBUG_DAC_RANGE=y
CONFIG_PGTABLE_LEVELS=2
CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"
CONFIG_IRQ_WORK=y

#
# Platform support
#
# CONFIG_PPC_CELL is not set
# CONFIG_PPC_CELL_NATIVE is not set
# CONFIG_PQ2ADS is not set
CONFIG_FSL_SOC_BOOKE=y
# CONFIG_BSC9131_RDB is not set
# CONFIG_C293_PCIE is not set
# CONFIG_BSC9132_QDS is not set
# CONFIG_MPC8540_ADS is not set
# CONFIG_MPC8560_ADS is not set
# CONFIG_MPC85xx_CDS is not set
# CONFIG_MPC85xx_MDS is not set
# CONFIG_MPC8536_DS is not set
# CONFIG_MPC85xx_DS is not set
# CONFIG_MPC85xx_RDB is not set
# CONFIG_P1010_RDB is not set
# CONFIG_P1022_DS is not set
# CONFIG_P1022_RDK is not set
# CONFIG_P1023_RDB is not set
# CONFIG_TWR_P102x is not set
# CONFIG_SOCRATES is not set
# CONFIG_KSI8560 is not set
# CONFIG_XES_MPC85xx is not set
# CONFIG_STX_GP3 is not set
# CONFIG_TQM8540 is not set
# CONFIG_TQM8541 is not set
# CONFIG_TQM8548 is not set
# CONFIG_TQM8555 is not set
# CONFIG_TQM8560 is not set
# CONFIG_SBC8548 is not set
# CONFIG_PPA8548 is not set
# CONFIG_GE_IMP3A is not set
# CONFIG_SGY_CTS1000 is not set
# CONFIG_MVME2500 is not set
# CONFIG_PPC_QEMU_E500 is not set
CONFIG_CORENET_GENERIC=y
# CONFIG_KVM_GUEST is not set
CONFIG_EPAPR_PARAVIRT=y
CONFIG_PPC_SMP_MUXED_IPI=y
# CONFIG_IPIC is not set
CONFIG_MPIC=y
# CONFIG_MPIC_TIMER is not set
CONFIG_PPC_EPAPR_HV_PIC=y
# CONFIG_MPIC_WEIRD is not set
CONFIG_MPIC_MSGR=y
# CONFIG_PPC_I8259 is not set
# CONFIG_PPC_RTAS is not set
# CONFIG_MMIO_NVRAM is not set
# CONFIG_MPIC_U3_HT_IRQS is not set
# CONFIG_PPC_MPC106 is not set
# CONFIG_PPC_970_NAP is not set
# CONFIG_PPC_P7_NAP is not set



On Wed, Dec 25, 2019 at 9:25 AM Scott Wood <oss@buserror.net> wrote:
>
> On Tue, 2019-12-24 at 09:35 +0800, Yingjie Bai wrote:
> > Hi Michael,
> > Thanks for pointing out the issue. My mistake...
> > This patch should indeed make sense only when
> > CONFIG_PHYS_64BIT=y
> >
> > I could not find corenet32_smp_defconfig, but I guess in your config,
> > CONFIG_PHYS_64BIT=n ?
> > I will update the patch later today
>
> corenet32_smp_defconfig is a makefile rule that pulls in multiple config
> fragments.  It has CONFIG_PHYS_64BIT=y, but __pa() returns an unsigned long
> regardless (which obviously needs to be fixed if DDR starting beyond 4G is to
> be supported).
>
> What 32-bit config are you using where this actually builds?
>
> -Scott
>
>

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Scott Wood]

On Wed, 2019-12-25 at 11:24 +0800, Yingjie Bai wrote:
> Hi Scott,
> 
> __pa() returns 64bit in my setup.
> 
> in arch/powerpc/include/asm/page.h
> 
> #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) +
> VIRT_PHYS_OFFSET))
> #define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET)
> #else
> #ifdef CONFIG_PPC64
> ...
> 
> 
> 
> /* See Description below for VIRT_PHYS_OFFSET */
> #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> #ifdef CONFIG_RELOCATABLE
> #define VIRT_PHYS_OFFSET virt_phys_offset
> #else
> #define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
> #endif
> #endif

OK, so it's the lack of CONFIG_RELOCATABLE causing the build to fail.  Ideally
we'd make __pa() consistently return phys_addr_t, even if the upper bits are
known to always be zero in a particular config.

-Scott

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Yingjie Bai]

Thanks Scott, I will test to see if returning phys_addr_t in __pa()
works for my setup.

And another thin I will test is to compile without CONFIG_RELOCATABLE
before resubmitting the patch.

On Wed, Dec 25, 2019 at 2:53 PM Scott Wood <oss@buserror.net> wrote:
>
> On Wed, 2019-12-25 at 11:24 +0800, Yingjie Bai wrote:
> > Hi Scott,
> >
> > __pa() returns 64bit in my setup.
> >
> > in arch/powerpc/include/asm/page.h
> >
> > #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> > #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) +
> > VIRT_PHYS_OFFSET))
> > #define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET)
> > #else
> > #ifdef CONFIG_PPC64
> > ...
> >
> >
> >
> > /* See Description below for VIRT_PHYS_OFFSET */
> > #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> > #ifdef CONFIG_RELOCATABLE
> > #define VIRT_PHYS_OFFSET virt_phys_offset
> > #else
> > #define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
> > #endif
> > #endif
>
> OK, so it's the lack of CONFIG_RELOCATABLE causing the build to fail.  Ideally
> we'd make __pa() consistently return phys_addr_t, even if the upper bits are
> known to always be zero in a particular config.
>
> -Scott
>
>

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Yingjie Bai]

Hi Scott,

Thanks for your time to review this patch

Based on your suggestion, I have verified below new patches that pass
compilation with and without CONFIG_RELOCATABLE

https://lore.kernel.org/patchwork/patch/1173548
https://lore.kernel.org/patchwork/patch/1173547

On Wed, Dec 25, 2019 at 3:19 PM Yingjie Bai <byj.tea@gmail.com> wrote:
>
> Thanks Scott, I will test to see if returning phys_addr_t in __pa()
> works for my setup.
>
> And another thin I will test is to compile without CONFIG_RELOCATABLE
> before resubmitting the patch.
>
> On Wed, Dec 25, 2019 at 2:53 PM Scott Wood <oss@buserror.net> wrote:
> >
> > On Wed, 2019-12-25 at 11:24 +0800, Yingjie Bai wrote:
> > > Hi Scott,
> > >
> > > __pa() returns 64bit in my setup.
> > >
> > > in arch/powerpc/include/asm/page.h
> > >
> > > #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> > > #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) +
> > > VIRT_PHYS_OFFSET))
> > > #define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET)
> > > #else
> > > #ifdef CONFIG_PPC64
> > > ...
> > >
> > >
> > >
> > > /* See Description below for VIRT_PHYS_OFFSET */
> > > #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> > > #ifdef CONFIG_RELOCATABLE
> > > #define VIRT_PHYS_OFFSET virt_phys_offset
> > > #else
> > > #define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
> > > #endif
> > > #endif
> >
> > OK, so it's the lack of CONFIG_RELOCATABLE causing the build to fail.  Ideally
> > we'd make __pa() consistently return phys_addr_t, even if the upper bits are
> > known to always be zero in a particular config.
> >
> > -Scott
> >
> >

Re: [PATCH] powerpc/mpc85xx: also write addr_h to spin table for 64bit boot entry

[Yingjie Bai]

Hi Scott,

Sorry for the late reply, I have checked the compilation error from
kbuild system, and found when CONFIG_PHYS_64BIT is not set,
phys_addr_t is 32bit, there is still "right shift count >= width of
type" error.
So I update the patches accordingly.

https://lore.kernel.org/patchwork/patch/1175560/
https://lore.kernel.org/patchwork/patch/1175559/


On Mon, Dec 30, 2019 at 3:41 PM Yingjie Bai <byj.tea@gmail.com> wrote:
>
> Hi Scott,
>
> Thanks for your time to review this patch
>
> Based on your suggestion, I have verified below new patches that pass
> compilation with and without CONFIG_RELOCATABLE
>
> https://lore.kernel.org/patchwork/patch/1173548
> https://lore.kernel.org/patchwork/patch/1173547
>
> On Wed, Dec 25, 2019 at 3:19 PM Yingjie Bai <byj.tea@gmail.com> wrote:
> >
> > Thanks Scott, I will test to see if returning phys_addr_t in __pa()
> > works for my setup.
> >
> > And another thin I will test is to compile without CONFIG_RELOCATABLE
> > before resubmitting the patch.
> >
> > On Wed, Dec 25, 2019 at 2:53 PM Scott Wood <oss@buserror.net> wrote:
> > >
> > > On Wed, 2019-12-25 at 11:24 +0800, Yingjie Bai wrote:
> > > > Hi Scott,
> > > >
> > > > __pa() returns 64bit in my setup.
> > > >
> > > > in arch/powerpc/include/asm/page.h
> > > >
> > > > #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> > > > #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) +
> > > > VIRT_PHYS_OFFSET))
> > > > #define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET)
> > > > #else
> > > > #ifdef CONFIG_PPC64
> > > > ...
> > > >
> > > >
> > > >
> > > > /* See Description below for VIRT_PHYS_OFFSET */
> > > > #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
> > > > #ifdef CONFIG_RELOCATABLE
> > > > #define VIRT_PHYS_OFFSET virt_phys_offset
> > > > #else
> > > > #define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
> > > > #endif
> > > > #endif
> > >
> > > OK, so it's the lack of CONFIG_RELOCATABLE causing the build to fail.  Ideally
> > > we'd make __pa() consistently return phys_addr_t, even if the upper bits are
> > > known to always be zero in a particular config.
> > >
> > > -Scott
> > >
> > >