[PATCH v3 4/4] clk: microchip: core: allow driver to be compiled with COMPILE_TEST

From: Brian Masney

Date: Fri Dec 05 2025 - 14:46:57 EST


This driver currently only supports builds against a PIC32 target. To
avoid future breakage in the future, let's update the Kconfig and the
driver so that it can be built with CONFIG_COMPILE_TEST enabled.

Note that with the existing asm calls is not how I'd want to do this
today if this was a new driver, however I don't have access to this
hardware. To avoid any breakage, let's keep the existing behavior.

Signed-off-by: Brian Masney <bmasney@xxxxxxxxxx>
---
drivers/clk/microchip/Kconfig | 2 +-
drivers/clk/microchip/clk-core.c | 32 +++++++++++++++++++++++---------
2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/clk/microchip/Kconfig b/drivers/clk/microchip/Kconfig
index 1b9e43eb54976b219a0277cc971f353fd6af226a..1e56a057319d97e20440fe4e107d26fa85c95ab1 100644
--- a/drivers/clk/microchip/Kconfig
+++ b/drivers/clk/microchip/Kconfig
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0

config COMMON_CLK_PIC32
- def_bool COMMON_CLK && MACH_PIC32
+ def_bool (COMMON_CLK && MACH_PIC32) || COMPILE_TEST

config MCHP_CLK_MPFS
bool "Clk driver for PolarFire SoC"
diff --git a/drivers/clk/microchip/clk-core.c b/drivers/clk/microchip/clk-core.c
index f467d7bc28c87a50fb18dc527574f973c4b7e615..fad4b45d908310ffb59e4ed57c55ae4266253444 100644
--- a/drivers/clk/microchip/clk-core.c
+++ b/drivers/clk/microchip/clk-core.c
@@ -9,7 +9,15 @@
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
+
+#if !defined(CONFIG_MACH_PIC32) && defined(CONFIG_COMPILE_TEST)
+#define PIC32_CLR(_reg) ((_reg) + 0x04)
+#define PIC32_SET(_reg) ((_reg) + 0x08)
+#define PIC32_INV(_reg) ((_reg) + 0x0C)
+#define pic32_syskey_unlock()
+#else
#include <asm/mach-pic32/pic32.h>
+#endif

#include "clk-core.h"

@@ -74,15 +82,21 @@
/* SoC specific clock needed during SPLL clock rate switch */
static struct clk_hw *pic32_sclk_hw;

-/* add instruction pipeline delay while CPU clock is in-transition. */
-#define cpu_nop5() \
-do { \
- __asm__ __volatile__("nop"); \
- __asm__ __volatile__("nop"); \
- __asm__ __volatile__("nop"); \
- __asm__ __volatile__("nop"); \
- __asm__ __volatile__("nop"); \
-} while (0)
+#if !defined(CONFIG_MACH_PIC32) && defined(CONFIG_COMPILE_TEST)
+#define cpu_nop5()
+#else
+{
+ /* add instruction pipeline delay while CPU clock is in-transition. */
+ #define cpu_nop5() \
+ do { \
+ __asm__ __volatile__("nop"); \
+ __asm__ __volatile__("nop"); \
+ __asm__ __volatile__("nop"); \
+ __asm__ __volatile__("nop"); \
+ __asm__ __volatile__("nop"); \
+ } while (0)
+}
+#endif

/* Perpheral bus clocks */
struct pic32_periph_clk {

--
2.52.0