New patch to review for coreboot: b086132 X86: make the SIPI num_starts a config variable
Ronald G. Minnich (rminnich@gmail.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/3796
-gerrit
commit b086132df15971624b80e10abeabc98fc5d58677 Author: Ronald G. Minnich rminnich@gmail.com Date: Mon Jul 22 20:17:18 2013 +0200
X86: make the SIPI num_starts a config variable
The code to figure out how to set num_starts was starting to get kludgy. It's a constant for a given CPU; constants should be constant; make it a config variable.
This change includes an example of how to override it. Build but not boot tested; drivers welcome.
Change-Id: Iddd906a707bb16251615c7b42f2bfb5a044379b4 Signed-off-by: Ronald G. Minnich rminnich@gmail.com --- src/arch/x86/Kconfig | 9 +++++++++ src/cpu/amd/model_10xxx/Kconfig | 4 ++++ src/cpu/x86/lapic/lapic_cpu_init.c | 12 +++--------- 3 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/src/arch/x86/Kconfig b/src/arch/x86/Kconfig index 581a048..0a21fcc 100644 --- a/src/arch/x86/Kconfig +++ b/src/arch/x86/Kconfig @@ -48,6 +48,15 @@ config MAX_REBOOT_CNT int default 3
+# This is something you almost certainly don't want to mess with. +# How many SIPIs do we send when starting up APs and cores? +# The answer in 2000 or so was '2'. Nowadays, on many systems, +# it is 1. Set a safe default here, and you can override it +# on reasonable platforms. +config NUM_IPI_STARTS + int + default 2 + # We had to rename the choice options under arch/ because otherwise # the options would conflict between different architectures despite # the if ARCH_xxx guarding the arch/xxx/Kconfig sourcing. diff --git a/src/cpu/amd/model_10xxx/Kconfig b/src/cpu/amd/model_10xxx/Kconfig index e4367f9..99358e0 100644 --- a/src/cpu/amd/model_10xxx/Kconfig +++ b/src/cpu/amd/model_10xxx/Kconfig @@ -8,6 +8,10 @@ config CPU_AMD_MODEL_10XXX
if CPU_AMD_MODEL_10XXX
+config NUM_IPI_STARTS + int + default 1 + config CPU_ADDR_BITS int default 48 diff --git a/src/cpu/x86/lapic/lapic_cpu_init.c b/src/cpu/x86/lapic/lapic_cpu_init.c index a3bab46..cd09280 100644 --- a/src/cpu/x86/lapic/lapic_cpu_init.c +++ b/src/cpu/x86/lapic/lapic_cpu_init.c @@ -101,7 +101,7 @@ static int lapic_start_cpu(unsigned long apicid) { int timeout; unsigned long send_status, accept_status; - int j, num_starts, maxlvt; + int j, maxlvt;
/* * Starting actual IPI sequence... @@ -167,20 +167,14 @@ static int lapic_start_cpu(unsigned long apicid) return 0; }
-#if !CONFIG_CPU_AMD_MODEL_10XXX - num_starts = 2; -#else - num_starts = 1; -#endif - /* * Run STARTUP IPI loop. */ - printk(BIOS_SPEW, "#startup loops: %d.\n", num_starts); + printk(BIOS_SPEW, "#startup loops: %d.\n", CONFIG_NUM_IPI_STARTS);
maxlvt = 4;
- for (j = 1; j <= num_starts; j++) { + for (j = 1; j <= CONFIG_NUM_IPI_STARTS; j++) { printk(BIOS_SPEW, "Sending STARTUP #%d to %lu.\n", j, apicid); lapic_read_around(LAPIC_SPIV); lapic_write(LAPIC_ESR, 0);
-
Ronald G. Minnich