Re: [PATCH 5/5] cpufreq: loongson3: Replace IOCSR read/write with MMIO ones

[Xi Ruoyao]

在 2026/8/18 20:39, Huacai Chen 写道:
> Our server productions (e.g. Loongson-3D6000/3E6000) can have multiple
> nodes in one package and SMC mailboxes are also per-node. However, IOCSR
> read/write can only perform on the current node, while sometimes we want
> to perform on other nodes (e.g. when switch governor, the get and target
> callbacks are not run on target core). So replace IOCSR read/write with
> MMIO ones.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
> ---
>   drivers/cpufreq/loongson3_cpufreq.c | 31 ++++++++++++++++++++++-------
>   1 file changed, 24 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/cpufreq/loongson3_cpufreq.c b/drivers/cpufreq/loongson3_cpufreq.c
> index c75c0e30e881..e5062cd62390 100644
> --- a/drivers/cpufreq/loongson3_cpufreq.c
> +++ b/drivers/cpufreq/loongson3_cpufreq.c
> @@ -164,6 +164,12 @@ union smc_message {
>   
>   #define FREQ_MAX_LEVEL			16
>   
> +#define MMIO_SMCMBX(node) \
> +	((void __iomem *)(IO_BASE | (u64)(node) << NODE_ADDRSPACE_SHIFT | LOONGSON_REG_BASE | LOONGARCH_IOCSR_SMCMBX))

NODE_ADDRSPACE_SHIFT is defined in numa.h so that file needs to be 
included, to avoid a build failure when NUMA is disabled (if NUMA is 
enabled, numa.h happens to be pulled in via some other headers).

Also I'd suggest to use nid_to_addrbase(node) instead of hard coding the 
shift for better readability.

With the changes:

Tested-by: Xi Ruoyao <xry111@xxxxxxxxxxx> # on XA61200