On Wed, 2015-10-07 at 17:00 +0300, Laurentiu Tudor wrote:
> On 10/07/2015 06:48 AM, Scott Wood wrote:
> > Use an AS=1 trampoline TLB entry to allow all normal TLB1 entries to
> > be loaded at once. This avoids the need to keep the translation that
> > code is executing from in the same TLB entry in the final TLB
> > configuration as during early boot, which in turn is helpful for
> > relocatable kernels (e.g. kdump) where the kernel is not running from
> > what would be the first TLB entry.
> >
> > On e6500, we limit map_mem_in_cams() to the primary hwthread of a
> > core (the boot cpu is always considered primary, as a kdump kernel
> > can be entered on any cpu). Each TLB only needs to be set up once,
> > and when we do, we don't want another thread to be running when we
> > create a temporary trampoline TLB1 entry.
> >
> > Signed-off-by: Scott Wood <scottwood at freescale.com>
> > ---
> > arch/powerpc/kernel/setup_64.c | 8 +++++
> > arch/powerpc/mm/fsl_booke_mmu.c | 15 ++++++++--
> > arch/powerpc/mm/mmu_decl.h | 1 +
> > arch/powerpc/mm/tlb_nohash.c | 19 +++++++++++-
> > arch/powerpc/mm/tlb_nohash_low.S | 63
> > ++++++++++++++++++++++++++++++++++++++++
> > 5 files changed, 102 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/powerpc/kernel/setup_64.c
> > b/arch/powerpc/kernel/setup_64.c
> > index bdcbb71..505ec2c 100644
> > --- a/arch/powerpc/kernel/setup_64.c
> > +++ b/arch/powerpc/kernel/setup_64.c
> > @@ -108,6 +108,14 @@ static void setup_tlb_core_data(void)
> > for_each_possible_cpu(cpu) {
> > int first = cpu_first_thread_sibling(cpu);
> >
> > + /*
> > + * If we boot via kdump on a non-primary thread,
> > + * make sure we point at the thread that actually
> > + * set up this TLB.
> > + */
> > + if (cpu_first_thread_sibling(boot_cpuid) == first)
> > + first = boot_cpuid;
> > +
> > paca[cpu].tcd_ptr = &paca[first].tcd;
> >
> > /*
> > diff --git a/arch/powerpc/mm/fsl_booke_mmu.c
> > b/arch/powerpc/mm/fsl_booke_mmu.c
> > index 354ba3c..36d3c55 100644
> > --- a/arch/powerpc/mm/fsl_booke_mmu.c
> > +++ b/arch/powerpc/mm/fsl_booke_mmu.c
> > @@ -105,8 +105,9 @@ unsigned long p_mapped_by_tlbcam(phys_addr_t pa)
> > * an unsigned long (for example, 32-bit implementations cannot support a
> > 4GB
> > * size).
> > */
> > -static void settlbcam(int index, unsigned long virt, phys_addr_t phys,
> > - unsigned long size, unsigned long flags, unsigned int pid)
> > +static void preptlbcam(int index, unsigned long virt, phys_addr_t phys,
> > + unsigned long size, unsigned long flags,
> > + unsigned int pid)
> > {
> > unsigned int tsize;
> >
> > @@ -141,7 +142,13 @@ static void settlbcam(int index, unsigned long virt,
> > phys_addr_t phys,
> > tlbcam_addrs[index].start = virt;
> > tlbcam_addrs[index].limit = virt + size - 1;
> > tlbcam_addrs[index].phys = phys;
> > +}
> >
> > +void settlbcam(int index, unsigned long virt, phys_addr_t phys,
>
>
> Nit: shouldn't this be left static? Also, now with this bulk TLB1 loading
> is it still used? Maybe it can be dropped.
You're right, it's an unneeded leftover. We might as well
s/preptlbcam/settlbcam/ as well to reduce churn.
-Scott
