| Message ID | 1362498756-395-1-git-send-email-Laurentiu.Tudor@freescale.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Scott Wood |
| Headers | show |
On Tue, Mar 05, 2013 at 05:52:36PM +0200, Laurentiu TUDOR wrote: > From: Tudor Laurentiu <laurentiu.tudor@freescale.com> > > The ePAPR para-virtualization needs to happen very early > otherwise the bytechannel based console will silently > drop some of the early boot messages. > > Before this patch, this is how the kernel log started: > ----------------------------------------------------- > > Brought up 2 CPUs > > devtmpfs: initialized > > NET: Registered protocol family 16 > [...] > ----------------------------------------------------- > > After the patch the early messages show up: > ----------------------------------------------------- > > Using P5020 DS machine description > > MMU: Supported page sizes > > 4 KB as direct > > 4096 KB as direct > [...] > ----------------------------------------------------- > > At console init, the kernel tried to flush the log buffer. > Since the paravirt was not yet initialized the console write > function failed silently, thus losing the buffered messages. [snip] > diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c > index 6da881b..ce092ac 100644 > --- a/arch/powerpc/kernel/setup_64.c > +++ b/arch/powerpc/kernel/setup_64.c > @@ -66,6 +66,7 @@ > #include <asm/code-patching.h> > #include <asm/kvm_ppc.h> > #include <asm/hugetlb.h> > +#include <asm/epapr_hcalls.h> > > #include "setup.h" > > @@ -599,6 +600,8 @@ void __init setup_arch(char **cmdline_p) > /* Initialize the MMU context management stuff */ > mmu_context_init(); > > + epapr_paravirt_init(); > + > kvm_linear_init(); > > /* Interrupt code needs to be 64K-aligned */ Is this early enough? There's udbg activity before this. Maybe it should even go before udbg_early_init... This would require converting the code to use the early device tree functions. -Scott
On 06/26/2013 02:14 AM, Scott Wood wrote: > On Tue, Mar 05, 2013 at 05:52:36PM +0200, Laurentiu TUDOR wrote: >> From: Tudor Laurentiu<laurentiu.tudor@freescale.com> >> >> The ePAPR para-virtualization needs to happen very early >> otherwise the bytechannel based console will silently >> drop some of the early boot messages. >> >> Before this patch, this is how the kernel log started: >> ----------------------------------------------------- >> > Brought up 2 CPUs >> > devtmpfs: initialized >> > NET: Registered protocol family 16 >> [...] >> ----------------------------------------------------- >> >> After the patch the early messages show up: >> ----------------------------------------------------- >> > Using P5020 DS machine description >> > MMU: Supported page sizes >> > 4 KB as direct >> > 4096 KB as direct >> [...] >> ----------------------------------------------------- >> >> At console init, the kernel tried to flush the log buffer. >> Since the paravirt was not yet initialized the console write >> function failed silently, thus losing the buffered messages. > [snip] >> diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c >> index 6da881b..ce092ac 100644 >> --- a/arch/powerpc/kernel/setup_64.c >> +++ b/arch/powerpc/kernel/setup_64.c >> @@ -66,6 +66,7 @@ >> #include<asm/code-patching.h> >> #include<asm/kvm_ppc.h> >> #include<asm/hugetlb.h> >> +#include<asm/epapr_hcalls.h> >> >> #include "setup.h" >> >> @@ -599,6 +600,8 @@ void __init setup_arch(char **cmdline_p) >> /* Initialize the MMU context management stuff */ >> mmu_context_init(); >> >> + epapr_paravirt_init(); >> + >> kvm_linear_init(); >> >> /* Interrupt code needs to be 64K-aligned */ > > Is this early enough? There's udbg activity before this. Maybe it > should even go before udbg_early_init... Right. I'll try moving it in machine_init(). > This would require converting > the code to use the early device tree functions. > I see. Had a look at that api and it seems pretty limited. I couldn't find a simple way of reading a property other than scanning the entire tree with of_scan_flat_dt(). --- Best Regards, Laurentiu
diff --git a/arch/powerpc/include/asm/epapr_hcalls.h b/arch/powerpc/include/asm/epapr_hcalls.h index d3d6342..544176e 100644 --- a/arch/powerpc/include/asm/epapr_hcalls.h +++ b/arch/powerpc/include/asm/epapr_hcalls.h @@ -105,6 +105,12 @@ extern bool epapr_paravirt_enabled; extern u32 epapr_hypercall_start[]; +#ifdef CONFIG_EPAPR_PARAVIRT +int __init epapr_paravirt_init(void); +#else +static inline int epapr_paravirt_init(void) { return 0; } +#endif + /* * We use "uintptr_t" to define a register because it's guaranteed to be a * 32-bit integer on a 32-bit platform, and a 64-bit integer on a 64-bit diff --git a/arch/powerpc/kernel/epapr_paravirt.c b/arch/powerpc/kernel/epapr_paravirt.c index f3eab85..9848713 100644 --- a/arch/powerpc/kernel/epapr_paravirt.c +++ b/arch/powerpc/kernel/epapr_paravirt.c @@ -28,7 +28,7 @@ extern u32 epapr_ev_idle_start[]; bool epapr_paravirt_enabled; -static int __init epapr_paravirt_init(void) +int __init epapr_paravirt_init(void) { struct device_node *hyper_node; const u32 *insts; @@ -58,4 +58,3 @@ static int __init epapr_paravirt_init(void) return 0; } -early_initcall(epapr_paravirt_init); diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c index a8f54ec..1464655 100644 --- a/arch/powerpc/kernel/setup_32.c +++ b/arch/powerpc/kernel/setup_32.c @@ -38,6 +38,7 @@ #include <asm/serial.h> #include <asm/udbg.h> #include <asm/mmu_context.h> +#include <asm/epapr_hcalls.h> #include "setup.h" @@ -327,4 +328,5 @@ void __init setup_arch(char **cmdline_p) /* Initialize the MMU context management stuff */ mmu_context_init(); + epapr_paravirt_init(); } diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 6da881b..ce092ac 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -66,6 +66,7 @@ #include <asm/code-patching.h> #include <asm/kvm_ppc.h> #include <asm/hugetlb.h> +#include <asm/epapr_hcalls.h> #include "setup.h" @@ -599,6 +600,8 @@ void __init setup_arch(char **cmdline_p) /* Initialize the MMU context management stuff */ mmu_context_init(); + epapr_paravirt_init(); + kvm_linear_init(); /* Interrupt code needs to be 64K-aligned */