Provide a default implementation of mips_cpc_default_phys_base() which
simply returns 0, and adjust mips_cpc_phys_base() to allow for
mips_cpc_default_phys_base() returning 0. This allows kernels which
include CPC support to be built without platform code & simply ignore
the CPC if it wasn't already enabled by the bootloader.
This fixes link failures such as the following from generic defconfigs:
arch/mips/built-in.o: In function `mips_cpc_phys_base':
arch/mips/kernel/mips-cpc.c:47: undefined reference to `mips_cpc_default_phys_base'
Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
---
Hi Ralf,
Please could this one be merged for v4.9 - it fixes some fallout due to
the CPC parts of the generic kernel series not being merged, which I had
overlooked when we discussed the series previously.
---
arch/mips/kernel/mips-cpc.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
index 2a45867..da64cd5 100644
--- a/arch/mips/kernel/mips-cpc.c
+++ b/arch/mips/kernel/mips-cpc.c
@@ -21,6 +21,11 @@ static DEFINE_PER_CPU_ALIGNED(spinlock_t, cpc_core_lock);
static DEFINE_PER_CPU_ALIGNED(unsigned long, cpc_core_lock_flags);
+__weak phys_addr_t mips_cpc_default_phys_base(void)
+{
+ return 0;
+}
+
/**
* mips_cpc_phys_base - retrieve the physical base address of the CPC
*
@@ -43,8 +48,12 @@ static phys_addr_t mips_cpc_phys_base(void)
if (cpc_base & CM_GCR_CPC_BASE_CPCEN_MSK)
return cpc_base & CM_GCR_CPC_BASE_CPCBASE_MSK;
- /* Otherwise, give it the default address & enable it */
+ /* Otherwise, use the default address */
cpc_base = mips_cpc_default_phys_base();
+ if (!cpc_base)
+ return cpc_base;
+
+ /* Enable the CPC, mapped at the default address */
write_gcr_cpc_base(cpc_base | CM_GCR_CPC_BASE_CPCEN_MSK);
return cpc_base;
}
--
2.10.0
