[PATCH 4.14 114/140] MIPS: CPC: Map registers using DT in mips_cpc_default_phys_base()

From: Greg Kroah-Hartman
Date: Tue Mar 13 2018 - 11:40:32 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Paul Burton <paul.burton@xxxxxxxx>

commit 791412dafbbfd860e78983d45cf71db603a82f67 upstream.

Reading mips_cpc_base value from the DT allows each platform to
define it according to its needs. This is especially convenient
for MIPS_GENERIC kernel where this kind of information should be
determined in runtime.

Use mti,mips-cpc compatible string with just a reg property to
specify the register location for your platform.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxx>
Signed-off-by: Miodrag Dinic <miodrag.dinic@xxxxxxxx>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@xxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Patchwork: https://patchwork.linux-mips.org/patch/18513/
Signed-off-by: James Hogan <jhogan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/mips/kernel/mips-cpc.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

--- a/arch/mips/kernel/mips-cpc.c
+++ b/arch/mips/kernel/mips-cpc.c
@@ -10,6 +10,8 @@

#include <linux/errno.h>
#include <linux/percpu.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/spinlock.h>

#include <asm/mips-cps.h>
@@ -22,6 +24,17 @@ static DEFINE_PER_CPU_ALIGNED(unsigned l

phys_addr_t __weak mips_cpc_default_phys_base(void)
{
+ struct device_node *cpc_node;
+ struct resource res;
+ int err;
+
+ cpc_node = of_find_compatible_node(of_root, NULL, "mti,mips-cpc");
+ if (cpc_node) {
+ err = of_address_to_resource(cpc_node, 0, &res);
+ if (!err)
+ return res.start;
+ }
+
return 0;
}