Date:   Mon, 13 Feb 2023 21:18:20 +0100
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>
Cc:     Michael Ellerman <mpe@ellerman.id.au>,
        Nicholas Piggin <npiggin@gmail.com>,
        Scott Wood <oss@buserror.net>, Sinan Akman <sinan@writeme.com>,
        Martin Kennedy <hurricos@gmail.com>,
        "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 6/8] powerpc/85xx: p2020: Define just one machine
 description
Message-ID: <20230213201820.xej7opc55e6obiti@pali>
References: <20221224211425.14983-1-pali@kernel.org>
 <20221224211425.14983-7-pali@kernel.org>
 <fc688761-5854-a171-c5e9-fae9eb25e798@csgroup.eu>
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On Monday 13 February 2023 20:08:52 Christophe Leroy wrote:
> Le 24/12/2022 à 22:14, Pali Rohár a écrit :
> > Combine machine descriptions and code of all P2020 boards into just one
> > generic unified P2020 machine description. This allows kernel to boot on
> > any P2020-based board with P2020 DTS file without need to patch kernel and
> > define a new machine description in 85xx powerpc platform directory.
> > 
> > Signed-off-by: Pali Rohár <pali@kernel.org>
> > ---
> >   arch/powerpc/platforms/85xx/p2020.c | 83 +++++++----------------------
> >   1 file changed, 19 insertions(+), 64 deletions(-)
> > 
> > diff --git a/arch/powerpc/platforms/85xx/p2020.c b/arch/powerpc/platforms/85xx/p2020.c
> > index adf3750abef9..b3fb600e1d83 100644
> > --- a/arch/powerpc/platforms/85xx/p2020.c
> > +++ b/arch/powerpc/platforms/85xx/p2020.c
> > @@ -156,83 +156,38 @@ static void __init p2020_setup_arch(void)
> >   #endif
> >   }
> >   
> > -#ifdef CONFIG_MPC85xx_DS
> > -machine_arch_initcall(p2020_ds, mpc85xx_common_publish_devices);
> > -#endif /* CONFIG_MPC85xx_DS */
> > -
> > -#ifdef CONFIG_MPC85xx_RDB
> > -machine_arch_initcall(p2020_rdb, mpc85xx_common_publish_devices);
> > -machine_arch_initcall(p2020_rdb_pc, mpc85xx_common_publish_devices);
> > -#endif /* CONFIG_MPC85xx_RDB */
> > +machine_arch_initcall(p2020, mpc85xx_common_publish_devices);
> >   
> >   /*
> >    * Called very early, device-tree isn't unflattened
> >    */
> > -#ifdef CONFIG_MPC85xx_DS
> > -static int __init p2020_ds_probe(void)
> > -{
> > -	return !!of_machine_is_compatible("fsl,P2020DS");
> > -}
> > -#endif /* CONFIG_MPC85xx_DS */
> > -
> > -#ifdef CONFIG_MPC85xx_RDB
> > -static int __init p2020_rdb_probe(void)
> > -{
> > -	if (of_machine_is_compatible("fsl,P2020RDB"))
> > -		return 1;
> > -	return 0;
> > -}
> > -
> > -static int __init p2020_rdb_pc_probe(void)
> > +static int __init p2020_probe(void)
> >   {
> > -	if (of_machine_is_compatible("fsl,P2020RDB-PC"))
> > -		return 1;
> > -	return 0;
> > +	struct device_node *p2020_cpu;
> > +
> > +	/*
> > +	 * There is no common compatible string for all P2020 boards.
> > +	 * The only common thing is "PowerPC,P2020@0" cpu node.
> > +	 * So check for P2020 board via this cpu node.
> > +	 */
> > +	p2020_cpu = of_find_node_by_path("/cpus/PowerPC,P2020@0");
> > +	if (!p2020_cpu)
> > +		return 0;
> > +
> > +	of_node_put(p2020_cpu);
> 
> of_node_put() already checks for nullity of its parameter, so you can 
> simplify stuff here, something like
> 
> 	p2020_cpu = of_find_node_by_path("/cpus/PowerPC,P2020@0");
> 	of_node_put(p2020_cpu);
> 
> 	return !!p2020_cpu;

Ok!

> > +	return 1;
> >   }
> > -#endif /* CONFIG_MPC85xx_RDB */
> > -
> > -#ifdef CONFIG_MPC85xx_DS
> > -define_machine(p2020_ds) {
> > -	.name			= "P2020 DS",
> > -	.probe			= p2020_ds_probe,
> > -	.setup_arch		= p2020_setup_arch,
> > -	.init_IRQ		= p2020_pic_init,
> > -#ifdef CONFIG_PCI
> > -	.pcibios_fixup_bus	= fsl_pcibios_fixup_bus,
> > -	.pcibios_fixup_phb      = fsl_pcibios_fixup_phb,
> > -#endif
> > -	.get_irq		= mpic_get_irq,
> > -	.calibrate_decr		= generic_calibrate_decr,
> > -	.progress		= udbg_progress,
> > -};
> > -#endif /* CONFIG_MPC85xx_DS */
> > -
> > -#ifdef CONFIG_MPC85xx_RDB
> > -define_machine(p2020_rdb) {
> > -	.name			= "P2020 RDB",
> > -	.probe			= p2020_rdb_probe,
> > -	.setup_arch		= p2020_setup_arch,
> > -	.init_IRQ		= p2020_pic_init,
> > -#ifdef CONFIG_PCI
> > -	.pcibios_fixup_bus	= fsl_pcibios_fixup_bus,
> > -	.pcibios_fixup_phb      = fsl_pcibios_fixup_phb,
> > -#endif
> > -	.get_irq		= mpic_get_irq,
> > -	.calibrate_decr		= generic_calibrate_decr,
> > -	.progress		= udbg_progress,
> > -};
> >   
> > -define_machine(p2020_rdb_pc) {
> > -	.name			= "P2020RDB-PC",
> > -	.probe			= p2020_rdb_pc_probe,
> > +define_machine(p2020) {
> > +	.name			= "Freescale P2020",
> > +	.probe			= p2020_probe,
> >   	.setup_arch		= p2020_setup_arch,
> >   	.init_IRQ		= p2020_pic_init,
> >   #ifdef CONFIG_PCI
> >   	.pcibios_fixup_bus	= fsl_pcibios_fixup_bus,
> > -	.pcibios_fixup_phb      = fsl_pcibios_fixup_phb,
> > +	.pcibios_fixup_phb	= fsl_pcibios_fixup_phb,
> >   #endif
> >   	.get_irq		= mpic_get_irq,
> >   	.calibrate_decr		= generic_calibrate_decr,
> >   	.progress		= udbg_progress,
> >   };
> > -#endif /* CONFIG_MPC85xx_RDB */