[PATCH] clk: stm32: fix clock array size for STM32MP21

[gabriel.fernandez at foss.st.com]

From: Gabriel Fernandez <gabriel.fernandez at foss.st.com>

STM32MP21_LAST_CLK is used as the number of entries of the onecell
clk_hw array allocated in stm32_rcc_clock_init(), and as the bound of
the clock IDs it can hold. It was wrongly set to CK_SCMI_KER_ETR (112),
which belongs to the SCMI clock ID range, whereas the RCC clock IDs
go up to CK_KER_STM (289).

As a result the array is too small, and registering a clock whose ID
is greater than 111 writes past the end of the allocated clk_hw array
(hws[cfg_clock->id] = hw), and consumers requesting such a clock
get rejected or read out of bounds.

Define STM32MP21_LAST_CLK as CK_KER_STM + 1 so that the array covers
all the RCC clock IDs.

No device tree node uses the STM32MP21 RCC driver yet, so there is no
need to backport this patch to stable kernels.

Fixes: 37ae8501cdb0 ("clk: stm32: introduce clocks for STM32MP21 platform")
Signed-off-by: Gabriel Fernandez <gabriel.fernandez at foss.st.com>
---
 drivers/clk/stm32/clk-stm32mp21.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/stm32/clk-stm32mp21.c b/drivers/clk/stm32/clk-stm32mp21.c
index bdb17419908c..961a228d8c64 100644
--- a/drivers/clk/stm32/clk-stm32mp21.c
+++ b/drivers/clk/stm32/clk-stm32mp21.c
@@ -17,8 +17,8 @@
 #include <dt-bindings/clock/st,stm32mp21-rcc.h>
 #include <dt-bindings/reset/st,stm32mp21-rcc.h>
 
-/* Max clock binding value */
-#define STM32MP21_LAST_CLK	CK_SCMI_KER_ETR
+/* Number of RCC clock bindings (highest RCC clock ID + 1) */
+#define STM32MP21_LAST_CLK	(CK_KER_STM + 1)
 
 /* Clock security definition */
 #define SECF_NONE		-1

base-commit: a90ee4305c4a5df72c11b31dacfdc76e00fcf78a
-- 
2.43.0