| Message ID | 20250217071934.86131-8-adityag@linux.ibm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Implement MPIPL for PowerNV | expand |
On 2/17/25 12:49, Aditya Gupta wrote: > Linux expect a "ibm,opal/dump" node to know whether MPIPL (aka fadump) > is supported on the hardware. > > Export the "ibm,opal/dump" node in QEMU's device tree for Linux to know > that PowerNV supports MPIPL. > > With the commit, kernel boots thinking fadump is supported, and reserves > memory regions for fadump if "fadump=on" is passed in kernel cmdline: > > Linux/PowerPC load: init=/bin/sh debug fadump=on > Finalizing device tree... flat tree at 0x20ebaca0 > [ 1.005765851,5] DUMP: Payload sent metadata tag : 0x800002a8 > [ 1.005980914,5] DUMP: Boot mem size : 0x40000000 > [ 0.000000] opal fadump: Kernel metadata addr: 800002a8 > [ 0.000000] fadump: Reserved 1024MB of memory at 0x00000040000000 (System RAM: 20480MB) > [ 0.000000] fadump: Initialized 0x40000000 bytes cma area at 1024MB from 0x400102a8 bytes of memory reserved for firmware-assisted dump > > Also, OPAL and Linux expect the "mpipl-boot" device tree node on a MPIPL > boot. Hence add "mpipl-boot" property in device tree on an MPIPL boot. > > Hence after crash, Linux knows when it's a MPIPL/fadump boot: > > [ 0.000000] opal fadump: Firmware-assisted dump is active. > [ 0.000000] fadump: Firmware-assisted dump is active. > [ 0.000000] fadump: Reserving 23552MB of memory at 0x00000040000000 for preserving crash data > > Do note that fadump boot in PowerNV seems to require more memory, > trying with 1GB causes this error by kernel: > > [ 0.000000] fadump: Failed to find memory chunk for reservation! > > And even with anything from 2GB - 19GB, the kernel fails to boot due to > some memory issues. > > Trying with >20GB memory is recommended for now > > Signed-off-by: Aditya Gupta <adityag@linux.ibm.com> > --- > hw/ppc/pnv.c | 49 ++++++++++++++++++++++++++++++++++++++++ > hw/ppc/pnv_sbe.c | 18 +++++++++++---- > include/hw/ppc/pnv_sbe.h | 4 ++++ > 3 files changed, 67 insertions(+), 4 deletions(-) > > diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c > index 11fd477b71be..39ed3f873e9a 100644 > --- a/hw/ppc/pnv.c > +++ b/hw/ppc/pnv.c > @@ -51,6 +51,7 @@ > #include "hw/ppc/pnv_chip.h" > #include "hw/ppc/pnv_xscom.h" > #include "hw/ppc/pnv_pnor.h" > +#include "hw/ppc/pnv_sbe.h" > > #include "hw/isa/isa.h" > #include "hw/char/serial-isa.h" > @@ -697,6 +698,26 @@ static void *pnv_dt_create(MachineState *machine) > pmc->dt_power_mgt(pnv, fdt); > } > > + /* Add "dump" node so kernel knows MPIPL (aka fadump) is supported */ > + off = fdt_add_subnode(fdt, 0, "ibm,opal"); > + if (off == -FDT_ERR_EXISTS) { > + off = fdt_path_offset(fdt, "/ibm,opal"); > + } > + > + _FDT(off); > + off = fdt_add_subnode(fdt, off, "dump"); > + _FDT(off); > + _FDT((fdt_setprop_string(fdt, off, "compatible", "ibm,opal-dump"))); > + > + /* Add kernel and initrd as fw-load-area */ > + uint64_t fw_load_area[4] = { > + cpu_to_be64(KERNEL_LOAD_ADDR), cpu_to_be64(KERNEL_MAX_SIZE), > + cpu_to_be64(INITRD_LOAD_ADDR), cpu_to_be64(INITRD_MAX_SIZE) > + }; > + > + _FDT((fdt_setprop(fdt, off, "fw-load-area", > + fw_load_area, sizeof(fw_load_area)))); > + Above could be wrapped in pnv_dt_mpipl(fdt) and called here? > return fdt; > } > > @@ -714,6 +735,7 @@ static void pnv_reset(MachineState *machine, ResetType type) > PnvMachineState *pnv = PNV_MACHINE(machine); > IPMIBmc *bmc; > void *fdt; > + int node_offset; > > qemu_devices_reset(type); > > @@ -744,6 +766,33 @@ static void pnv_reset(MachineState *machine, ResetType type) > _FDT((fdt_pack(fdt))); > } > > + /* > + * If it's a MPIPL boot, add the "mpipl-boot" property, and reset the > + * boolean for MPIPL boot for next boot > + */ > + if (pnv_sbe_is_mpipl_boot()) { > + void *fdt_copy = g_malloc0(FDT_MAX_SIZE); Where is this getting free'ed ? > + > + /* Create a writable copy of the fdt */ > + _FDT((fdt_open_into(fdt, fdt_copy, FDT_MAX_SIZE))); > + > + node_offset = fdt_path_offset(fdt_copy, "/ibm,opal/dump"); > + _FDT((fdt_appendprop_u64(fdt_copy, node_offset, "mpipl-boot", 1))); > + > + /* Update the fdt, and free the original fdt */ > + if (fdt != machine->fdt) { > + /* > + * Only free the fdt if it's not machine->fdt, to prevent > + * double free, since we already free machine->fdt later > + */ > + g_free(fdt); > + } > + fdt = fdt_copy; > + > + /* This boot is an MPIPL, reset the boolean for next boot */ > + pnv_sbe_reset_is_next_boot_mpipl(); > + } > + Could above be wrapped in pnv_reset_mpipl(fdt) and called if pnv_sbe_is_mpipl_boot is true? > qemu_fdt_dumpdtb(fdt, fdt_totalsize(fdt)); > cpu_physical_memory_write(PNV_FDT_ADDR, fdt, fdt_totalsize(fdt)); > > diff --git a/hw/ppc/pnv_sbe.c b/hw/ppc/pnv_sbe.c > index 3b50667226b5..671dc81c9501 100644 > --- a/hw/ppc/pnv_sbe.c > +++ b/hw/ppc/pnv_sbe.c > @@ -216,6 +216,18 @@ struct proc_dump_area { > __be32 act_size; /* Actual data size */ > } __packed; > > +static bool is_next_boot_mpipl; > + > +bool pnv_sbe_is_mpipl_boot(void) > +{ > + return is_next_boot_mpipl; > +} > + > +void pnv_sbe_reset_is_next_boot_mpipl(void) > +{ > + is_next_boot_mpipl = false; > +} > + > static void pnv_sbe_set_host_doorbell(PnvSBE *sbe, uint64_t val) > { > val &= SBE_HOST_RESPONSE_MASK; /* Is this right? What does HW do? */ > @@ -334,10 +346,8 @@ static void pnv_sbe_power9_xscom_ctrl_write(void *opaque, hwaddr addr, > /* Save processor state */ > pnv_mpipl_save_proc_regs(); > > - /* > - * TODO: Pass `mpipl` node in device tree to signify next > - * boot is an MPIPL boot > - */ > + /* Mark next boot as Memory-preserving boot */ > + is_next_boot_mpipl = true; > > /* Then do a guest reset */ > /* > diff --git a/include/hw/ppc/pnv_sbe.h b/include/hw/ppc/pnv_sbe.h > index f6cbcf990ed9..94bbdc7b6414 100644 > --- a/include/hw/ppc/pnv_sbe.h > +++ b/include/hw/ppc/pnv_sbe.h > @@ -56,4 +56,8 @@ struct PnvSBEClass { > /* Helper to access stashed SKIBOOT_BASE */ > bool pnv_sbe_mpipl_skiboot_base(void); > > +/* Helpers to know if next boot is MPIPL boot */ > +bool pnv_sbe_is_mpipl_boot(void); > +void pnv_sbe_reset_is_next_boot_mpipl(void); Usually we have a set along with reset and helpers for modifying struct members. Above helpers for a gloabl var seems a bit un-necessary. I guess we want to keep such global vars inside relevant struct. Thanks Harsh > + > #endif /* PPC_PNV_SBE_H */
diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c index 11fd477b71be..39ed3f873e9a 100644 --- a/hw/ppc/pnv.c +++ b/hw/ppc/pnv.c @@ -51,6 +51,7 @@ #include "hw/ppc/pnv_chip.h" #include "hw/ppc/pnv_xscom.h" #include "hw/ppc/pnv_pnor.h" +#include "hw/ppc/pnv_sbe.h" #include "hw/isa/isa.h" #include "hw/char/serial-isa.h" @@ -697,6 +698,26 @@ static void *pnv_dt_create(MachineState *machine) pmc->dt_power_mgt(pnv, fdt); } + /* Add "dump" node so kernel knows MPIPL (aka fadump) is supported */ + off = fdt_add_subnode(fdt, 0, "ibm,opal"); + if (off == -FDT_ERR_EXISTS) { + off = fdt_path_offset(fdt, "/ibm,opal"); + } + + _FDT(off); + off = fdt_add_subnode(fdt, off, "dump"); + _FDT(off); + _FDT((fdt_setprop_string(fdt, off, "compatible", "ibm,opal-dump"))); + + /* Add kernel and initrd as fw-load-area */ + uint64_t fw_load_area[4] = { + cpu_to_be64(KERNEL_LOAD_ADDR), cpu_to_be64(KERNEL_MAX_SIZE), + cpu_to_be64(INITRD_LOAD_ADDR), cpu_to_be64(INITRD_MAX_SIZE) + }; + + _FDT((fdt_setprop(fdt, off, "fw-load-area", + fw_load_area, sizeof(fw_load_area)))); + return fdt; } @@ -714,6 +735,7 @@ static void pnv_reset(MachineState *machine, ResetType type) PnvMachineState *pnv = PNV_MACHINE(machine); IPMIBmc *bmc; void *fdt; + int node_offset; qemu_devices_reset(type); @@ -744,6 +766,33 @@ static void pnv_reset(MachineState *machine, ResetType type) _FDT((fdt_pack(fdt))); } + /* + * If it's a MPIPL boot, add the "mpipl-boot" property, and reset the + * boolean for MPIPL boot for next boot + */ + if (pnv_sbe_is_mpipl_boot()) { + void *fdt_copy = g_malloc0(FDT_MAX_SIZE); + + /* Create a writable copy of the fdt */ + _FDT((fdt_open_into(fdt, fdt_copy, FDT_MAX_SIZE))); + + node_offset = fdt_path_offset(fdt_copy, "/ibm,opal/dump"); + _FDT((fdt_appendprop_u64(fdt_copy, node_offset, "mpipl-boot", 1))); + + /* Update the fdt, and free the original fdt */ + if (fdt != machine->fdt) { + /* + * Only free the fdt if it's not machine->fdt, to prevent + * double free, since we already free machine->fdt later + */ + g_free(fdt); + } + fdt = fdt_copy; + + /* This boot is an MPIPL, reset the boolean for next boot */ + pnv_sbe_reset_is_next_boot_mpipl(); + } + qemu_fdt_dumpdtb(fdt, fdt_totalsize(fdt)); cpu_physical_memory_write(PNV_FDT_ADDR, fdt, fdt_totalsize(fdt)); diff --git a/hw/ppc/pnv_sbe.c b/hw/ppc/pnv_sbe.c index 3b50667226b5..671dc81c9501 100644 --- a/hw/ppc/pnv_sbe.c +++ b/hw/ppc/pnv_sbe.c @@ -216,6 +216,18 @@ struct proc_dump_area { __be32 act_size; /* Actual data size */ } __packed; +static bool is_next_boot_mpipl; + +bool pnv_sbe_is_mpipl_boot(void) +{ + return is_next_boot_mpipl; +} + +void pnv_sbe_reset_is_next_boot_mpipl(void) +{ + is_next_boot_mpipl = false; +} + static void pnv_sbe_set_host_doorbell(PnvSBE *sbe, uint64_t val) { val &= SBE_HOST_RESPONSE_MASK; /* Is this right? What does HW do? */ @@ -334,10 +346,8 @@ static void pnv_sbe_power9_xscom_ctrl_write(void *opaque, hwaddr addr, /* Save processor state */ pnv_mpipl_save_proc_regs(); - /* - * TODO: Pass `mpipl` node in device tree to signify next - * boot is an MPIPL boot - */ + /* Mark next boot as Memory-preserving boot */ + is_next_boot_mpipl = true; /* Then do a guest reset */ /* diff --git a/include/hw/ppc/pnv_sbe.h b/include/hw/ppc/pnv_sbe.h index f6cbcf990ed9..94bbdc7b6414 100644 --- a/include/hw/ppc/pnv_sbe.h +++ b/include/hw/ppc/pnv_sbe.h @@ -56,4 +56,8 @@ struct PnvSBEClass { /* Helper to access stashed SKIBOOT_BASE */ bool pnv_sbe_mpipl_skiboot_base(void); +/* Helpers to know if next boot is MPIPL boot */ +bool pnv_sbe_is_mpipl_boot(void); +void pnv_sbe_reset_is_next_boot_mpipl(void); + #endif /* PPC_PNV_SBE_H */
Linux expect a "ibm,opal/dump" node to know whether MPIPL (aka fadump) is supported on the hardware. Export the "ibm,opal/dump" node in QEMU's device tree for Linux to know that PowerNV supports MPIPL. With the commit, kernel boots thinking fadump is supported, and reserves memory regions for fadump if "fadump=on" is passed in kernel cmdline: Linux/PowerPC load: init=/bin/sh debug fadump=on Finalizing device tree... flat tree at 0x20ebaca0 [ 1.005765851,5] DUMP: Payload sent metadata tag : 0x800002a8 [ 1.005980914,5] DUMP: Boot mem size : 0x40000000 [ 0.000000] opal fadump: Kernel metadata addr: 800002a8 [ 0.000000] fadump: Reserved 1024MB of memory at 0x00000040000000 (System RAM: 20480MB) [ 0.000000] fadump: Initialized 0x40000000 bytes cma area at 1024MB from 0x400102a8 bytes of memory reserved for firmware-assisted dump Also, OPAL and Linux expect the "mpipl-boot" device tree node on a MPIPL boot. Hence add "mpipl-boot" property in device tree on an MPIPL boot. Hence after crash, Linux knows when it's a MPIPL/fadump boot: [ 0.000000] opal fadump: Firmware-assisted dump is active. [ 0.000000] fadump: Firmware-assisted dump is active. [ 0.000000] fadump: Reserving 23552MB of memory at 0x00000040000000 for preserving crash data Do note that fadump boot in PowerNV seems to require more memory, trying with 1GB causes this error by kernel: [ 0.000000] fadump: Failed to find memory chunk for reservation! And even with anything from 2GB - 19GB, the kernel fails to boot due to some memory issues. Trying with >20GB memory is recommended for now Signed-off-by: Aditya Gupta <adityag@linux.ibm.com> --- hw/ppc/pnv.c | 49 ++++++++++++++++++++++++++++++++++++++++ hw/ppc/pnv_sbe.c | 18 +++++++++++---- include/hw/ppc/pnv_sbe.h | 4 ++++ 3 files changed, 67 insertions(+), 4 deletions(-)