[PATCH v8 02/16] RISC-V: Add riscv_get_intc_hartid() function

[Sunil V L]

Hi Anup,

On Tue, Sep 12, 2023 at 11:19:14PM +0530, Anup Patel wrote:
> We add a common riscv_get_intc_hartid() which help device drivers to
> get hartid of the HART associated with a INTC (i.e. local interrupt
> controller) fwnode. This new function is more generic compared to
> the existing riscv_of_parent_hartid() function hence we also replace
> use of riscv_of_parent_hartid() with riscv_get_intc_hartid().
> 
> Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> ---
>  arch/riscv/include/asm/processor.h |  4 +++-
>  arch/riscv/kernel/cpu.c            | 13 ++++++++++++-
>  drivers/irqchip/irq-riscv-intc.c   |  2 +-
>  drivers/irqchip/irq-sifive-plic.c  |  3 ++-
>  4 files changed, 18 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> index 3e23e1786d05..3ce64b3bea4e 100644
> --- a/arch/riscv/include/asm/processor.h
> +++ b/arch/riscv/include/asm/processor.h
> @@ -119,7 +119,9 @@ static inline void wait_for_interrupt(void)
>  struct device_node;
>  int riscv_of_processor_hartid(struct device_node *node, unsigned long *hartid);
>  int riscv_early_of_processor_hartid(struct device_node *node, unsigned long *hartid);
> -int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid);
> +
> +struct fwnode_handle;
> +int riscv_get_intc_hartid(struct fwnode_handle *node, unsigned long *hartid);
>  
>  extern void riscv_fill_hwcap(void);
>  extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index 157ace8b262c..ee583eac3c5b 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -123,7 +123,8 @@ int __init riscv_early_of_processor_hartid(struct device_node *node, unsigned lo
>   * To achieve this, we walk up the DT tree until we find an active
>   * RISC-V core (HART) node and extract the cpuid from it.
>   */
> -int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
> +static int riscv_of_parent_hartid(struct device_node *node,
> +				  unsigned long *hartid)
>  {
>  	for (; node; node = node->parent) {
>  		if (of_device_is_compatible(node, "riscv")) {
> @@ -139,6 +140,16 @@ int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
>  	return -1;
>  }
>  
> +/* Find hart ID of the INTC fwnode. */
> +int riscv_get_intc_hartid(struct fwnode_handle *node, unsigned long *hartid)
> +{
> +	/* Extend this function ACPI in the future. */

As per Marc's feedback, we can't use swnode for ACPI irchips. So, there
is no need to create this wrapper function and this patch can be
dropped.

Thanks,
Sunil

> +	if (!is_of_node(node))
> +		return -ENODEV;
> +
> +	return riscv_of_parent_hartid(to_of_node(node), hartid);
> +}
> +
>  DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
>  
>  unsigned long riscv_cached_mvendorid(unsigned int cpu_id)
> diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c
> index 4adeee1bc391..65f4a2afb381 100644
> --- a/drivers/irqchip/irq-riscv-intc.c
> +++ b/drivers/irqchip/irq-riscv-intc.c
> @@ -143,7 +143,7 @@ static int __init riscv_intc_init(struct device_node *node,
>  	int rc;
>  	unsigned long hartid;
>  
> -	rc = riscv_of_parent_hartid(node, &hartid);
> +	rc = riscv_get_intc_hartid(of_fwnode_handle(node), &hartid);
>  	if (rc < 0) {
>  		pr_warn("unable to find hart id for %pOF\n", node);
>  		return 0;
> diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
> index e1484905b7bd..56b0544b1f27 100644
> --- a/drivers/irqchip/irq-sifive-plic.c
> +++ b/drivers/irqchip/irq-sifive-plic.c
> @@ -477,7 +477,8 @@ static int __init __plic_init(struct device_node *node,
>  			continue;
>  		}
>  
> -		error = riscv_of_parent_hartid(parent.np, &hartid);
> +		error = riscv_get_intc_hartid(of_fwnode_handle(parent.np),
> +					      &hartid);
>  		if (error < 0) {
>  			pr_warn("failed to parse hart ID for context %d.\n", i);
>  			continue;
> -- 
> 2.34.1
>