| Message ID | 1366957045-21133-1-git-send-email-Bharat.Bhushan@freescale.com |
|---|---|
| State | New |
| Headers | show |
On 26.04.2013, at 08:17, Bharat Bhushan wrote: > ePAPR defines the initial values of cpu registers. This patch initialize > the GPRs as per ePAPR specification. > > This resolves the issue of guest reboot/reset (guest hang on reboot). Why does it hang only on reboot, not on initial bootup? > > Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> > Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com> > --- > hw/ppc/e500.c | 7 +++++++ > 1 files changed, 7 insertions(+), 0 deletions(-) > > diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c > index c1bdb6b..a47f976 100644 > --- a/hw/ppc/e500.c > +++ b/hw/ppc/e500.c > @@ -37,6 +37,7 @@ > #include "qemu/host-utils.h" > #include "hw/pci-host/ppce500.h" > > +#define EPAPR_MAGIC (0x45504150) > #define BINARY_DEVICE_TREE_FILE "mpc8544ds.dtb" > #define UIMAGE_LOAD_BASE 0 > #define DTC_LOAD_PAD 0x1800000 > @@ -444,6 +445,12 @@ static void ppce500_cpu_reset(void *opaque) Does ePAPR mention anything wrt GPR state of secondary CPUs? > cs->halted = 0; > env->gpr[1] = (16<<20) - 8; > env->gpr[3] = bi->dt_base; > + env->gpr[4] = 0; > + env->gpr[5] = 0; > + env->gpr[6] = EPAPR_MAGIC; > + env->gpr[7] = (64 * 1024 * 1024); What is this? Alex > + env->gpr[8] = 0; > + env->gpr[9] = 0; > env->nip = bi->entry; > mmubooke_create_initial_mapping(env); > } > -- > 1.7.0.4 > >
> -----Original Message----- > From: Alexander Graf [mailto:agraf@suse.de] > Sent: Friday, April 26, 2013 11:51 AM > To: Bhushan Bharat-R65777 > Cc: qemu-ppc@nongnu.org; qemu-devel@nongnu.org; Wood Scott-B07421; Bhushan > Bharat-R65777; Yoder Stuart-B08248 > Subject: Re: [PATCH] ppc: initialize GPRs as per epapr > > > On 26.04.2013, at 08:17, Bharat Bhushan wrote: > > > ePAPR defines the initial values of cpu registers. This patch > > initialize the GPRs as per ePAPR specification. > > > > This resolves the issue of guest reboot/reset (guest hang on reboot). > > Why does it hang only on reboot, not on initial bootup? may be memory pointed by env pointer are zero initialized initially. Reboot also not always hangs. I have seen reboot mostly working on e500v2/e500mc and mostly hanging on e5500. > > > > > Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> > > Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com> > > --- > > hw/ppc/e500.c | 7 +++++++ > > 1 files changed, 7 insertions(+), 0 deletions(-) > > > > diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c index c1bdb6b..a47f976 > > 100644 > > --- a/hw/ppc/e500.c > > +++ b/hw/ppc/e500.c > > @@ -37,6 +37,7 @@ > > #include "qemu/host-utils.h" > > #include "hw/pci-host/ppce500.h" > > > > +#define EPAPR_MAGIC (0x45504150) > > #define BINARY_DEVICE_TREE_FILE "mpc8544ds.dtb" > > #define UIMAGE_LOAD_BASE 0 > > #define DTC_LOAD_PAD 0x1800000 > > @@ -444,6 +445,12 @@ static void ppce500_cpu_reset(void *opaque) > > Does ePAPR mention anything wrt GPR state of secondary CPUs? Yes, I think we handle this in hw/ppc/ppce500_spin.c > > > cs->halted = 0; > > env->gpr[1] = (16<<20) - 8; > > env->gpr[3] = bi->dt_base; > > + env->gpr[4] = 0; > > + env->gpr[5] = 0; > > + env->gpr[6] = EPAPR_MAGIC; > > + env->gpr[7] = (64 * 1024 * 1024); > > What is this? Size of initial TLB ( should be big enough to cover kernel handler). I do not see ePAPR defines any value, I set this to 64M. -Bharat > > > Alex > > > + env->gpr[8] = 0; > > + env->gpr[9] = 0; > > env->nip = bi->entry; > > mmubooke_create_initial_mapping(env); > > } > > -- > > 1.7.0.4 > > > > >
On 26.04.2013, at 08:51, Bhushan Bharat-R65777 wrote: > > >> -----Original Message----- >> From: Alexander Graf [mailto:agraf@suse.de] >> Sent: Friday, April 26, 2013 11:51 AM >> To: Bhushan Bharat-R65777 >> Cc: qemu-ppc@nongnu.org; qemu-devel@nongnu.org; Wood Scott-B07421; Bhushan >> Bharat-R65777; Yoder Stuart-B08248 >> Subject: Re: [PATCH] ppc: initialize GPRs as per epapr >> >> >> On 26.04.2013, at 08:17, Bharat Bhushan wrote: >> >>> ePAPR defines the initial values of cpu registers. This patch >>> initialize the GPRs as per ePAPR specification. >>> >>> This resolves the issue of guest reboot/reset (guest hang on reboot). >> >> Why does it hang only on reboot, not on initial bootup? > > may be memory pointed by env pointer are zero initialized initially. > Reboot also not always hangs. I have seen reboot mostly working on e500v2/e500mc and mostly hanging on e5500. Yes, they're all zero initialized. I'm surprised that got things working. > >> >>> >>> Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> >>> Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com> >>> --- >>> hw/ppc/e500.c | 7 +++++++ >>> 1 files changed, 7 insertions(+), 0 deletions(-) >>> >>> diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c index c1bdb6b..a47f976 >>> 100644 >>> --- a/hw/ppc/e500.c >>> +++ b/hw/ppc/e500.c >>> @@ -37,6 +37,7 @@ >>> #include "qemu/host-utils.h" >>> #include "hw/pci-host/ppce500.h" >>> >>> +#define EPAPR_MAGIC (0x45504150) >>> #define BINARY_DEVICE_TREE_FILE "mpc8544ds.dtb" >>> #define UIMAGE_LOAD_BASE 0 >>> #define DTC_LOAD_PAD 0x1800000 >>> @@ -444,6 +445,12 @@ static void ppce500_cpu_reset(void *opaque) >> >> Does ePAPR mention anything wrt GPR state of secondary CPUs? > > Yes, I think we handle this in hw/ppc/ppce500_spin.c > >> >>> cs->halted = 0; >>> env->gpr[1] = (16<<20) - 8; >>> env->gpr[3] = bi->dt_base; >>> + env->gpr[4] = 0; >>> + env->gpr[5] = 0; >>> + env->gpr[6] = EPAPR_MAGIC; >>> + env->gpr[7] = (64 * 1024 * 1024); >> >> What is this? > > Size of initial TLB ( should be big enough to cover kernel handler). I do not see ePAPR defines any value, I set this to 64M. It's dynamic. Please set it to the actual size of the initial TLB mapping we create. Alex
On Fri, Apr 26, 2013 at 08:21:24AM +0200, Alexander Graf wrote: > > On 26.04.2013, at 08:17, Bharat Bhushan wrote: > > > ePAPR defines the initial values of cpu registers. This patch initialize > > the GPRs as per ePAPR specification. > > > > This resolves the issue of guest reboot/reset (guest hang on reboot). > > Why does it hang only on reboot, not on initial bootup? > > > > > Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> > > Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com> > > --- > > hw/ppc/e500.c | 7 +++++++ > > 1 files changed, 7 insertions(+), 0 deletions(-) > > > > diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c > > index c1bdb6b..a47f976 100644 > > --- a/hw/ppc/e500.c > > +++ b/hw/ppc/e500.c > > @@ -37,6 +37,7 @@ > > #include "qemu/host-utils.h" > > #include "hw/pci-host/ppce500.h" > > > > +#define EPAPR_MAGIC (0x45504150) > > #define BINARY_DEVICE_TREE_FILE "mpc8544ds.dtb" > > #define UIMAGE_LOAD_BASE 0 > > #define DTC_LOAD_PAD 0x1800000 > > @@ -444,6 +445,12 @@ static void ppce500_cpu_reset(void *opaque) > > Does ePAPR mention anything wrt GPR state of secondary CPUs? Yes and no. The entry point state for secondary CPUs depends on the "enable-method" used to start the CPU. The spin-table enable method defined in ePAPR gives some information on GPR state, although the constraints are much weaker than for the boot cpu. Platform specific enable-methods would have to define their own entry point requirements.
On 04/26/2013 01:59:10 AM, Alexander Graf wrote: > > On 26.04.2013, at 08:51, Bhushan Bharat-R65777 wrote: > > > > > > >> -----Original Message----- > >> From: Alexander Graf [mailto:agraf@suse.de] > >> Sent: Friday, April 26, 2013 11:51 AM > >> To: Bhushan Bharat-R65777 > >> Cc: qemu-ppc@nongnu.org; qemu-devel@nongnu.org; Wood Scott-B07421; > Bhushan > >> Bharat-R65777; Yoder Stuart-B08248 > >> Subject: Re: [PATCH] ppc: initialize GPRs as per epapr > >> > >> > >> On 26.04.2013, at 08:17, Bharat Bhushan wrote: > >> > >>> ePAPR defines the initial values of cpu registers. This patch > >>> initialize the GPRs as per ePAPR specification. > >>> > >>> This resolves the issue of guest reboot/reset (guest hang on > reboot). > >> > >> Why does it hang only on reboot, not on initial bootup? > > > > may be memory pointed by env pointer are zero initialized initially. > > Reboot also not always hangs. I have seen reboot mostly working on > e500v2/e500mc and mostly hanging on e5500. > > Yes, they're all zero initialized. I'm surprised that got things > working. head_64.S assumes it's being booted from Open Firmware if r5 is non-zero -- this is why ePAPR requires r5 to be zero. -Scott
diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c index c1bdb6b..a47f976 100644 --- a/hw/ppc/e500.c +++ b/hw/ppc/e500.c @@ -37,6 +37,7 @@ #include "qemu/host-utils.h" #include "hw/pci-host/ppce500.h" +#define EPAPR_MAGIC (0x45504150) #define BINARY_DEVICE_TREE_FILE "mpc8544ds.dtb" #define UIMAGE_LOAD_BASE 0 #define DTC_LOAD_PAD 0x1800000 @@ -444,6 +445,12 @@ static void ppce500_cpu_reset(void *opaque) cs->halted = 0; env->gpr[1] = (16<<20) - 8; env->gpr[3] = bi->dt_base; + env->gpr[4] = 0; + env->gpr[5] = 0; + env->gpr[6] = EPAPR_MAGIC; + env->gpr[7] = (64 * 1024 * 1024); + env->gpr[8] = 0; + env->gpr[9] = 0; env->nip = bi->entry; mmubooke_create_initial_mapping(env); }