[Skiboot] [PATCH v2 2/7] skiboot: Find the IMA catalog

Hemant Kumar hemant at linux.vnet.ibm.com
Tue Dec 6 05:21:47 AEDT 2016



On 11/22/2016 06:46 AM, Oliver O'Halloran wrote:
> On Fri, Nov 18, 2016 at 1:10 PM, Hemant Kumar <hemant at linux.vnet.ibm.com> wrote:
>> IMA (In Memory Accumulation) catalog is a repository of information
>> about the Performance Monitoring Units (PMUs) and their events under
>> the IMA infrastructure. The information include :
>>   - The PMU names
>>   - Event names
>>   - Event description
>>   - Event offsets
>>   - Event scale
>>   - Event unit
>>
>> The catalog is provided as a flattened device tree (dtb). Processors
>> with different PVR values may have different PMU or event names. Hence,
>> for each processor, there can be multiple device tree binaries (dtbs)
>> containing the IMA information. Each of the dtb is compressed and forms
>> a sub-partition inside the PNOR partition "IMA_CATALOG". Here is a link
>> to the commit adding this partition to PNOR :
>> https://github.com/open-power/pnor/commit/c940142c6dc64dd176096dc648f433c889919e84
>>
>> So, each compressed dtb forms a sub-partition inside the IMA_CATALOG
>> partition and can be accessed/loaded through a sub-partition id which
>> is nothing but the PVR id. Based on the current processor's PVR, the
>> appropriate sub-partion will be loaded.
>>
>>   IMA_CATALOG
>>    partition
>>   -----------   Sub-id (E.g)
>>   |         |
>>   |Catalog 1|    0x100
>>   |---------|
>>   |         |
>>   |Catalog 2|    0x200    <------  Current processor's PVR (0x200)
>>   |---------|
>>   ...
>>
>> In the above example, if the current processor's PVR is 0x200, catalog 2
>> should be loaded.
> As far as I know a PNOR built for one system and/or processor revision
> isn't going to be portable to another, so why are we doing this?

Right. A PNOR image built for one system/processor isn't portable to 
another. However, within a single processor, there can be multiple 
revisions, where some of the PMUs or their events can be changed. Hence, 
this design.

>
>> Note however, that the catalog information is in the form of a dtb and
>> the dtb is compressed too. So, the sub-partition loaded must be
>> decompressed first before we can actually use it (which is done in
>> subsequent patches).
> You could add the decompression library before this patch and avoid
> this awkward split entirely

Sure.

This and other issues have been fixed in v3 : 
https://lists.ozlabs.org/pipermail/skiboot/2016-December/005729.html

--
Thanks,
Hemant Kumar


>> Signed-off-by: Hemant Kumar <hemant at linux.vnet.ibm.com>
>> ---
>> Chaneglog:
>> v1 -> v2:
>>   - Moved the macro checks for power8 to a separate function is_power8().
>>
>>   core/flash.c       |  1 +
>>   core/init.c        |  4 ++++
>>   hw/Makefile.inc    |  2 +-
>>   hw/ima.c           | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>   include/ima.h      |  2 ++
>>   include/platform.h |  1 +
>>   6 files changed, 78 insertions(+), 1 deletion(-)
>>   create mode 100644 hw/ima.c
>>
>> diff --git a/core/flash.c b/core/flash.c
>> index 92de421..32b32dc 100644
>> --- a/core/flash.c
>> +++ b/core/flash.c
>> @@ -416,6 +416,7 @@ static struct {
>>          { RESOURCE_ID_KERNEL,   RESOURCE_SUBID_NONE,            "BOOTKERNEL" },
>>          { RESOURCE_ID_INITRAMFS,RESOURCE_SUBID_NONE,            "ROOTFS" },
>>          { RESOURCE_ID_CAPP,     RESOURCE_SUBID_SUPPORTED,       "CAPP" },
>> +       { RESOURCE_ID_CATALOG,  RESOURCE_SUBID_SUPPORTED,       "IMA_CATALOG" },
>>   };
>>
>>   /* This mimics the hostboot SBE format */
>> diff --git a/core/init.c b/core/init.c
>> index 43ce3a0..94a4708 100644
>> --- a/core/init.c
>> +++ b/core/init.c
>> @@ -47,6 +47,7 @@
>>   #include <nvram.h>
>>   #include <libstb/stb.h>
>>   #include <libstb/container.h>
>> +#include <ima.h>
>>
>>   enum proc_gen proc_gen;
>>
>> @@ -903,6 +904,9 @@ void __noreturn __nomcount main_cpu_entry(const void *fdt)
>>          /* Init SLW related stuff, including fastsleep */
>>          slw_init();
>>
>> +       /* Init IMA related stuff (load the IMA dtb into memory) */
>> +       ima_init();
>> +
>>          op_display(OP_LOG, OP_MOD_INIT, 0x0002);
>>
>>          /* Read in NVRAM and set it up */
>> diff --git a/hw/Makefile.inc b/hw/Makefile.inc
>> index a433c2b..8bcd203 100644
>> --- a/hw/Makefile.inc
>> +++ b/hw/Makefile.inc
>> @@ -1,7 +1,7 @@
>>   # -*-Makefile-*-
>>   SUBDIRS += hw
>>   HW_OBJS  = xscom.o chiptod.o gx.o cec.o lpc.o lpc-uart.o psi.o
>> -HW_OBJS += homer.o slw.o occ.o fsi-master.o centaur.o
>> +HW_OBJS += homer.o slw.o occ.o fsi-master.o centaur.o ima.o
>>   HW_OBJS += nx.o nx-rng.o nx-crypto.o nx-842.o
>>   HW_OBJS += p7ioc.o p7ioc-inits.o p7ioc-phb.o
>>   HW_OBJS += phb3.o sfc-ctrl.o fake-rtc.o bt.o p8-i2c.o prd.o
>> diff --git a/hw/ima.c b/hw/ima.c
>> new file mode 100644
>> index 0000000..7f9184f
>> --- /dev/null
>> +++ b/hw/ima.c
>> @@ -0,0 +1,69 @@
>> +/* Copyright 2016 IBM Corp.
>> + *
>> + * Licensed under the Apache License, Version 2.0 (the "License");
>> + * you may not use this file except in compliance with the License.
>> + * You may obtain a copy of the License at
>> + *
>> + *     http://www.apache.org/licenses/LICENSE-2.0
>> + *
>> + * Unless required by applicable law or agreed to in writing, software
>> + * distributed under the License is distributed on an "AS IS" BASIS,
>> + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
>> + * implied.
>> + * See the License for the specific language governing permissions and
>> + * limitations under the License.
>> + */
>> +
>> +#include <skiboot.h>
>> +#include <xscom.h>
>> +#include <ima.h>
>> +#include <chip.h>
>> +
>> +static bool is_power8(void)
>> +{
>> +       struct proc_chip *chip;
>> +
>> +       chip = get_chip(this_cpu()->chip_id);
>> +       if ((chip->type == PROC_CHIP_P8_MURANO) ||
>> +           (chip->type == PROC_CHIP_P8_VENICE) ||
>> +           (chip->type == PROC_CHIP_P8_NAPLES))
>> +               return true;
>> +       return false;
>> +}
> why not just use proc_gen?
>> +
>> +/*
>> + * Fetch the IMA Catalog partition and find the appropriate sub-partition
>> + * based on the platform's PVR.
>> + */
>> +void ima_init(void)
>> +{
>> +       char *buf = NULL;
>> +       size_t size = IMA_DTB_SIZE;
>> +       uint32_t pvr = mfspr(SPR_PVR);
>> +       int ret;
>> +
>> +       /* Disable this for power 8 */
>> +       if (is_power8())
>> +               return;
> Why are we disabling this for P8?   not supporting it on P8
>
> Is it a P9 only feature? What about P7?
>
>> +
>> +       buf = malloc(IMA_DTB_SIZE);
>> +       if (!buf) {
>> +               prerror("IMA: unable to allocate memory\n");
>> +               return;
>> +       }
>> +
>> +       ret = start_preload_resource(RESOURCE_ID_CATALOG,
>> +                                       pvr, buf, &size);
>> +       if (ret != OPAL_SUCCESS)
>> +               goto err;
>> +
>> +       ret = wait_for_resource_loaded(RESOURCE_ID_CATALOG,
>> +                                         pvr);
>> +       if (ret != OPAL_SUCCESS) {
>> +               prerror("IMA: unable to load the catalog\n");
>> +               goto err;
>> +       }
>> +
>> +err:
>> +       free(buf);
>> +}
>
>
>> diff --git a/include/ima.h b/include/ima.h
>> index f628ee0..20f3c39 100644
>> --- a/include/ima.h
>> +++ b/include/ima.h
>> @@ -109,4 +109,6 @@ struct ima_chip_cb
>>   #define NEST_IMA_ENABLE                        0x1
>>   #define NEST_IMA_DISABLE               0x2
>>
>> +void ima_init(void);
>> +
>>   #endif /* __IMA_H */
>> diff --git a/include/platform.h b/include/platform.h
>> index 334c0a4..02adb2f 100644
>> --- a/include/platform.h
>> +++ b/include/platform.h
>> @@ -27,6 +27,7 @@ enum resource_id {
>>          RESOURCE_ID_KERNEL,
>>          RESOURCE_ID_INITRAMFS,
>>          RESOURCE_ID_CAPP,
>> +       RESOURCE_ID_CATALOG,
>>   };
>>   #define RESOURCE_SUBID_NONE 0
>>   #define RESOURCE_SUBID_SUPPORTED 1
>> --
>> 2.7.4
>>
>> _______________________________________________
>> Skiboot mailing list
>> Skiboot at lists.ozlabs.org
>> https://lists.ozlabs.org/listinfo/skiboot



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