Re: [PATCH V3 12/20] RISC-V: cpufeature: Add ACPI support in riscv_fill_hwcap()

From: Sunil V L <sunilvl@ventanamicro.com>
To: Andrew Jones <ajones@ventanamicro.com>
Cc: linux-riscv@lists.infradead.org, linux-acpi@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	"Rafael J . Wysocki" <rafael@kernel.org>,
	Len Brown <lenb@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
	Marc Zyngier <maz@kernel.org>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Jonathan Corbet <corbet@lwn.net>,
	Anup Patel <apatel@ventanamicro.com>,
	Atish Patra <atishp@rivosinc.com>,
	'Conor Dooley ' <conor.dooley@microchip.com>,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>
Subject: Re: [PATCH V3 12/20] RISC-V: cpufeature: Add ACPI support in riscv_fill_hwcap()
Date: Fri, 3 Mar 2023 23:25:16 +0530	[thread overview]
Message-ID: <ZAI0hFuJjA8ikf2p@sunil-laptop> (raw)
In-Reply-To: <20230303161647.mksonnutzaw4d3gb@orel>

On Fri, Mar 03, 2023 at 05:16:47PM +0100, Andrew Jones wrote:
> On Fri, Mar 03, 2023 at 07:06:39PM +0530, Sunil V L wrote:
> > On ACPI based systems, the information about the hart
> > like ISA is provided by the RISC-V Hart Capabilities Table (RHCT).
> > Enable filling up hwcap structure based on the information in RHCT.
> > 
> > Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
> > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > ---
> >  arch/riscv/kernel/cpufeature.c | 41 ++++++++++++++++++++++++++--------
> >  1 file changed, 32 insertions(+), 9 deletions(-)
> > 
> > diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> > index 59d58ee0f68d..478dbf129922 100644
> > --- a/arch/riscv/kernel/cpufeature.c
> > +++ b/arch/riscv/kernel/cpufeature.c
> > @@ -6,6 +6,7 @@
> >   * Copyright (C) 2017 SiFive
> >   */
> >  
> > +#include <linux/acpi.h>
> >  #include <linux/bitmap.h>
> >  #include <linux/ctype.h>
> >  #include <linux/libfdt.h>
> > @@ -13,6 +14,8 @@
> >  #include <linux/memory.h>
> >  #include <linux/module.h>
> >  #include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <asm/acpi.h>
> >  #include <asm/alternative.h>
> >  #include <asm/cacheflush.h>
> >  #include <asm/errata_list.h>
> > @@ -91,7 +94,9 @@ void __init riscv_fill_hwcap(void)
> >  	char print_str[NUM_ALPHA_EXTS + 1];
> >  	int i, j, rc;
> >  	unsigned long isa2hwcap[26] = {0};
> > -	unsigned long hartid;
> > +	struct acpi_table_header *rhct;
> > +	acpi_status status;
> > +	unsigned int cpu;
> >  
> >  	isa2hwcap['i' - 'a'] = COMPAT_HWCAP_ISA_I;
> >  	isa2hwcap['m' - 'a'] = COMPAT_HWCAP_ISA_M;
> > @@ -104,18 +109,33 @@ void __init riscv_fill_hwcap(void)
> >  
> >  	bitmap_zero(riscv_isa, RISCV_ISA_EXT_MAX);
> >  
> > -	for_each_of_cpu_node(node) {
> > +	if (!acpi_disabled) {
> > +		status = acpi_get_table(ACPI_SIG_RHCT, 0, &rhct);
> > +		if (ACPI_FAILURE(status))
> > +			return;
> > +	}
> > +
> > +	for_each_possible_cpu(cpu) {
> >  		unsigned long this_hwcap = 0;
> >  		DECLARE_BITMAP(this_isa, RISCV_ISA_EXT_MAX);
> >  		const char *temp;
> >  
> > -		rc = riscv_of_processor_hartid(node, &hartid);
> > -		if (rc < 0)
> > -			continue;
> 
> The above is an unrelated cleanup and should be in a separate patch.
> 
Okay, let me split this.

Thanks,
Sunil