[U-Boot] Question regarding cpu_get_count(..)
Hi
I tried my luck on the u-boot irc channel but nobody cared so I am asking this here again. Does cpu_get_count(..) return the number of physical CPUs or the number of logical CPUs?
I am currently preparing a patch set which adds arch/x86/cpu/queensbay/cpu.c and there I need to specify a struct cpu_ops with a function called get_count(). But what must I return (physical vs. logical CPU count)?
Hi Christian,
On Fri, Apr 6, 2018 at 2:55 PM, Christian Gmeiner christian.gmeiner@gmail.com wrote:
Hi
I tried my luck on the u-boot irc channel but nobody cared so I am asking this here again. Does cpu_get_count(..) return the number of physical CPUs or the number of logical CPUs?
I am currently preparing a patch set which adds arch/x86/cpu/queensbay/cpu.c and there I need to specify a struct cpu_ops with a function called get_count(). But what must I return (physical vs. logical CPU count)?
It's logical CPUs, say you have one physical CPU, each with dual-threads, so get_count() returns 2.
But Intel CrownBay already supports SMP in U-Boot. What patch are you working on?
Regards, Bin
Hi Bin
2018-04-06 9:47 GMT+02:00 Bin Meng bmeng.cn@gmail.com:
Hi Christian,
On Fri, Apr 6, 2018 at 2:55 PM, Christian Gmeiner christian.gmeiner@gmail.com wrote:
Hi
I tried my luck on the u-boot irc channel but nobody cared so I am asking this here again. Does cpu_get_count(..) return the number of physical CPUs or the number of logical CPUs?
I am currently preparing a patch set which adds arch/x86/cpu/queensbay/cpu.c and there I need to specify a struct cpu_ops with a function called get_count(). But what must I return (physical vs. logical CPU count)?
It's logical CPUs, say you have one physical CPU, each with dual-threads, so get_count() returns 2.
Good to know. I am looking into an issue where vxworks 7 intel gen is not able to detect the correct amount of physical and logical CPUs (on a blob UEFI-Bios). I compared the new platform with an older queensbay based one the there are some discrepancies. As vx7 makes use of a handful of BIOS tables I thought I start at the root (get_count()) and move up. So as a result of this that means that the MP table has one "Processor Entry" per logical CPU - or? I tired to get that information for the spec but failed.
But Intel CrownBay already supports SMP in U-Boot. What patch are you working on?
I am out of office today and do not have access to my wip git rep :( But I needed to set some speed frequency registers.. but can tell you more on Monday.
Hi Bin
2018-04-06 10:30 GMT+02:00 Christian Gmeiner christian.gmeiner@gmail.com:
Hi Bin
2018-04-06 9:47 GMT+02:00 Bin Meng bmeng.cn@gmail.com:
Hi Christian,
On Fri, Apr 6, 2018 at 2:55 PM, Christian Gmeiner christian.gmeiner@gmail.com wrote:
Hi
I tried my luck on the u-boot irc channel but nobody cared so I am asking this here again. Does cpu_get_count(..) return the number of physical CPUs or the number of logical CPUs?
I am currently preparing a patch set which adds arch/x86/cpu/queensbay/cpu.c and there I need to specify a struct cpu_ops with a function called get_count(). But what must I return (physical vs. logical CPU count)?
It's logical CPUs, say you have one physical CPU, each with dual-threads, so get_count() returns 2.
Good to know. I am looking into an issue where vxworks 7 intel gen is not able to detect the correct amount of physical and logical CPUs (on a blob UEFI-Bios). I compared the new platform with an older queensbay based one the there are some discrepancies. As vx7 makes use of a handful of BIOS tables I thought I start at the root (get_count()) and move up. So as a result of this that means that the MP table has one "Processor Entry" per logical CPU - or? I tired to get that information for the spec but failed.
But Intel CrownBay already supports SMP in U-Boot. What patch are you working on?
I am out of office today and do not have access to my wip git rep :( But I needed to set some speed frequency registers.. but can tell you more on Monday.
Okay.. yeah I need to configure speed: https://hastebin.com/toqihobali.cpp
So the end result is to get all BIOS tables standard conform and vx7 should be happy - I hope.
Hi Christian,
On Mon, Apr 9, 2018 at 3:52 PM, Christian Gmeiner christian.gmeiner@gmail.com wrote:
Hi Bin
2018-04-06 10:30 GMT+02:00 Christian Gmeiner christian.gmeiner@gmail.com:
Hi Bin
2018-04-06 9:47 GMT+02:00 Bin Meng bmeng.cn@gmail.com:
Hi Christian,
On Fri, Apr 6, 2018 at 2:55 PM, Christian Gmeiner christian.gmeiner@gmail.com wrote:
Hi
I tried my luck on the u-boot irc channel but nobody cared so I am asking this here again. Does cpu_get_count(..) return the number of physical CPUs or the number of logical CPUs?
I am currently preparing a patch set which adds arch/x86/cpu/queensbay/cpu.c and there I need to specify a struct cpu_ops with a function called get_count(). But what must I return (physical vs. logical CPU count)?
It's logical CPUs, say you have one physical CPU, each with dual-threads, so get_count() returns 2.
Good to know. I am looking into an issue where vxworks 7 intel gen is not able to detect the correct amount of physical and logical CPUs (on a blob UEFI-Bios). I compared the new platform with an older queensbay based one the there are some discrepancies. As vx7 makes use of a handful of BIOS tables I thought I start at the root (get_count()) and move up. So as a result of this that means that the MP table has one "Processor Entry" per logical CPU - or? I tired to get that information for the spec but failed.
But Intel CrownBay already supports SMP in U-Boot. What patch are you working on?
I am out of office today and do not have access to my wip git rep :( But I needed to set some speed frequency registers.. but can tell you more on Monday.
Okay.. yeah I need to configure speed: https://hastebin.com/toqihobali.cpp
So the end result is to get all BIOS tables standard conform and vx7 should be happy - I hope.
I am not sure I understand the mods here. Are you saying that vx7 is not happy due to U-Boot is missing some core speed register configuration?
Regards, Bin
2018-04-09 10:26 GMT+02:00 Bin Meng bmeng.cn@gmail.com:
Hi Christian,
On Mon, Apr 9, 2018 at 3:52 PM, Christian Gmeiner christian.gmeiner@gmail.com wrote:
Hi Bin
2018-04-06 10:30 GMT+02:00 Christian Gmeiner christian.gmeiner@gmail.com:
Hi Bin
2018-04-06 9:47 GMT+02:00 Bin Meng bmeng.cn@gmail.com:
Hi Christian,
On Fri, Apr 6, 2018 at 2:55 PM, Christian Gmeiner christian.gmeiner@gmail.com wrote:
Hi
I tried my luck on the u-boot irc channel but nobody cared so I am asking this here again. Does cpu_get_count(..) return the number of physical CPUs or the number of logical CPUs?
I am currently preparing a patch set which adds arch/x86/cpu/queensbay/cpu.c and there I need to specify a struct cpu_ops with a function called get_count(). But what must I return (physical vs. logical CPU count)?
It's logical CPUs, say you have one physical CPU, each with dual-threads, so get_count() returns 2.
Good to know. I am looking into an issue where vxworks 7 intel gen is not able to detect the correct amount of physical and logical CPUs (on a blob UEFI-Bios). I compared the new platform with an older queensbay based one the there are some discrepancies. As vx7 makes use of a handful of BIOS tables I thought I start at the root (get_count()) and move up. So as a result of this that means that the MP table has one "Processor Entry" per logical CPU - or? I tired to get that information for the spec but failed.
But Intel CrownBay already supports SMP in U-Boot. What patch are you working on?
I am out of office today and do not have access to my wip git rep :( But I needed to set some speed frequency registers.. but can tell you more on Monday.
Okay.. yeah I need to configure speed: https://hastebin.com/toqihobali.cpp
So the end result is to get all BIOS tables standard conform and vx7 should be happy - I hope.
I am not sure I understand the mods here. Are you saying that vx7 is not happy due to U-Boot is missing some core speed register configuration?
No - I am happy with the code basis as is. In order to fix some performance issues regarding cache I ended adding cpu.c. That was some months ago.
Now some guys and me need to bring up vx7 smp on a handful of targets and we are seeing some wired vxCpuIdTopology() outputs on different targets. Looks like u-boot is okay but a vendor binary bios has problems
https://hastebin.com/qojenuqoge.js
To sum it up: * cpu_get_count(..) needs to return the number of logical CPUs. * The generated MP-Table has one "Processor Entry" per logical CPU
I will prepare a proper patch for the cpu.c addition during the week.
participants (2)
-
Bin Meng -
Christian Gmeiner