From eda3d33c685ff62524500681249e4c8e2e8dbb8c Mon Sep 17 00:00:00 2001 From: James Hogan Date: Thu, 29 May 2014 10:16:36 +0100 Subject: [PATCH] MIPS: KVM: Override guest kernel timer frequency directly The KVM_HOST_FREQ Kconfig symbol was used by KVM guest kernels to override the timer frequency calculation to a value based on the host frequency. Now that the KVM timer emulation is implemented independent of the host timer frequency and defaults to 100MHz, adjust the working of CONFIG_KVM_HOST_FREQ to match. The Kconfig symbol now specifies the guest timer frequency directly, and has been renamed accordingly to KVM_GUEST_TIMER_FREQ. It now defaults to 100MHz too and the help text is updated to make it clear that a zero value will allow the normal timer frequency calculation to take place (based on the emulated RTC). Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: Gleb Natapov Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: Sanjay Lal Acked-by: Ralf Baechle Signed-off-by: Paolo Bonzini --- arch/mips/Kconfig | 12 ++++++------ arch/mips/mti-malta/malta-time.c | 14 ++------------ 2 files changed, 8 insertions(+), 18 deletions(-) diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 5cd695f905a1..5e0014e864f3 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1756,14 +1756,14 @@ config KVM_GUEST help Select this option if building a guest kernel for KVM (Trap & Emulate) mode -config KVM_HOST_FREQ - int "KVM Host Processor Frequency (MHz)" +config KVM_GUEST_TIMER_FREQ + int "Count/Compare Timer Frequency (MHz)" depends on KVM_GUEST - default 500 + default 100 help - Select this option if building a guest kernel for KVM to skip - RTC emulation when determining guest CPU Frequency. Instead, the guest - processor frequency is automatically derived from the host frequency. + Set this to non-zero if building a guest kernel for KVM to skip RTC + emulation when determining guest CPU Frequency. Instead, the guest's + timer frequency is specified directly. choice prompt "Kernel page size" diff --git a/arch/mips/mti-malta/malta-time.c b/arch/mips/mti-malta/malta-time.c index 319009912142..3778a359f3ad 100644 --- a/arch/mips/mti-malta/malta-time.c +++ b/arch/mips/mti-malta/malta-time.c @@ -74,18 +74,8 @@ static void __init estimate_frequencies(void) unsigned int giccount = 0, gicstart = 0; #endif -#if defined (CONFIG_KVM_GUEST) && defined (CONFIG_KVM_HOST_FREQ) - unsigned int prid = read_c0_prid() & (PRID_COMP_MASK | PRID_IMP_MASK); - - /* - * XXXKYMA: hardwire the CPU frequency to Host Freq/4 - */ - count = (CONFIG_KVM_HOST_FREQ * 1000000) >> 3; - if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) && - (prid != (PRID_COMP_MIPS | PRID_IMP_25KF))) - count *= 2; - - mips_hpt_frequency = count; +#if defined(CONFIG_KVM_GUEST) && CONFIG_KVM_GUEST_TIMER_FREQ + mips_hpt_frequency = CONFIG_KVM_GUEST_TIMER_FREQ * 1000000; return; #endif -- GitLab