| Message ID | 20220129162726.1154501-3-guoren@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | Add thead,c900-plic support | expand |
On Sun, Jan 30, 2022 at 2:32 AM Marc Zyngier <maz@kernel.org> wrote: > > On Sat, 29 Jan 2022 16:27:26 +0000, > guoren@kernel.org wrote: > > > > From: Guo Ren <guoren@linux.alibaba.com> > > > > The thead,c900-plic has been used in opensbi to distinguish > > PLIC [1]. Although PLICs have the same behaviors in Linux, > > they are different hardware with some custom initializing in > > firmware(opensbi). > > > > [1]: https://github.com/riscv-software-src/opensbi/commit/78c2b19218bd62653b9fb31623a42ced45f38ea6 > > > > Signed-off-by: Guo Ren <guoren@linux.alibaba.com> > > Cc: Anup Patel <anup@brainfault.org> > > Cc: Marc Zyngier <maz@kernel.org> > > Cc: Palmer Dabbelt <palmer@dabbelt.com> > > Cc: Samuel Holland <samuel@sholland.org> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > --- > > drivers/irqchip/irq-sifive-plic.c | 25 +++++++++++++++++++++++-- > > 1 file changed, 23 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c > > index 259065d271ef..245655928076 100644 > > --- a/drivers/irqchip/irq-sifive-plic.c > > +++ b/drivers/irqchip/irq-sifive-plic.c > > @@ -172,7 +172,7 @@ static void plic_irq_eoi(struct irq_data *d) > > } > > } > > > > -static struct irq_chip plic_chip = { > > +static struct irq_chip sifive_plic_chip = { > > .name = "SiFive PLIC", > > .irq_mask = plic_irq_mask, > > .irq_unmask = plic_irq_unmask, > > @@ -182,12 +182,24 @@ static struct irq_chip plic_chip = { > > #endif > > }; > > > > +static struct irq_chip thead_plic_chip = { > > + .name = "T-Head PLIC", > > + .irq_mask = plic_irq_mask, > > + .irq_unmask = plic_irq_unmask, > > + .irq_eoi = plic_irq_eoi, > > +#ifdef CONFIG_SMP > > + .irq_set_affinity = plic_set_affinity, > > +#endif > > +}; > > For pure entertainment, let's compare the two structures: > > static struct irq_chip plic_chip = { > .name = "SiFive PLIC", > .irq_mask = plic_irq_mask, > .irq_unmask = plic_irq_unmask, > .irq_eoi = plic_irq_eoi, > #ifdef CONFIG_SMP > .irq_set_affinity = plic_set_affinity, > #endif > }; > > Oh wait: a string. Must be really important. Not. No, pls see below comment. > > > + > > +static struct irq_chip *def_plic_chip = &sifive_plic_chip; > > + > > static int plic_irqdomain_map(struct irq_domain *d, unsigned int irq, > > irq_hw_number_t hwirq) > > { > > struct plic_priv *priv = d->host_data; > > > > - irq_domain_set_info(d, irq, hwirq, &plic_chip, d->host_data, > > + irq_domain_set_info(d, irq, hwirq, def_plic_chip, d->host_data, > > handle_fasteoi_irq, NULL, NULL); > > irq_set_noprobe(irq); > > irq_set_affinity(irq, &priv->lmask); > > @@ -396,5 +408,14 @@ static int __init plic_init(struct device_node *node, > > return error; > > } > > > > +static int __init thead_c900_plic_init(struct device_node *node, > > + struct device_node *parent) > > +{ > > + def_plic_chip = &thead_plic_chip; > > + > > + return plic_init(node, parent); > > +} > > + > > IRQCHIP_DECLARE(sifive_plic, "sifive,plic-1.0.0", plic_init); > > IRQCHIP_DECLARE(riscv_plic0, "riscv,plic0", plic_init); /* for legacy systems */ > > +IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", thead_c900_plic_init); > > Sorry, but I can't see any point to this patch. You didn't see the link I've put in the patch. In that opensbi patch: intc: interrupt-controller@10000000 { #interrupt-cells = <1>; - compatible = "riscv,plic0"; + compatible = "allwinner,sun20i-d1-plic", + "thead,c900-plic"; +#define THEAD_PLIC_CTRL_REG 0x1ffffc + +static void thead_plic_plat_init(struct plic_data *pd) +{ + writel_relaxed(BIT(0), (void *)pd->addr + THEAD_PLIC_CTRL_REG); +} + static const struct fdt_match irqchip_plic_match[] = { { .compatible = "riscv,plic0" }, { .compatible = "sifive,plic-1.0.0" }, + { .compatible = "thead,c900-plic", + .data = thead_plic_plat_init }, { }, }; We've changed the compatible name for thead,c900-plic, and there is no riscv,plic0 / sifive,plic-1.0.0 in dts. Without the patch, the newest opensbi + newest Linux would be broken in the Allwinner D1 dev board. > > M. > > -- > Without deviation from the norm, progress is not possible.
On Sun, 30 Jan 2022 13:09:21 +0000, Guo Ren <guoren@kernel.org> wrote: > > On Sun, Jan 30, 2022 at 6:28 PM Marc Zyngier <maz@kernel.org> wrote: > > > > On Sun, 30 Jan 2022 04:39:34 +0000, > > Guo Ren <guoren@kernel.org> wrote: > > > > > > > +IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", plic_init); > > > I think we should give clear info in /proc/interrupts. I hope we could > > > keep thead_plic_init. > > > > Why? There is no material difference at the driver level, and > > /proc/interrupts won't be the target of a branding exercise (which > > this series seems to be all about). > It's not a branding exercise, the series just correct the broken code > & incorrect /proc/interrupts display. There is *nothing* incorrect in /proc/interrupt. If anything, changing the string *is* an ABI change, for no good reason. M.
On Sun, Jan 30, 2022 at 10:59 PM Marc Zyngier <maz@kernel.org> wrote: > > On Sun, 30 Jan 2022 13:09:21 +0000, > Guo Ren <guoren@kernel.org> wrote: > > > > On Sun, Jan 30, 2022 at 6:28 PM Marc Zyngier <maz@kernel.org> wrote: > > > > > > On Sun, 30 Jan 2022 04:39:34 +0000, > > > Guo Ren <guoren@kernel.org> wrote: > > > > > > > > > +IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", plic_init); > > > > I think we should give clear info in /proc/interrupts. I hope we could > > > > keep thead_plic_init. > > > > > > Why? There is no material difference at the driver level, and > > > /proc/interrupts won't be the target of a branding exercise (which > > > this series seems to be all about). > > It's not a branding exercise, the series just correct the broken code > > & incorrect /proc/interrupts display. > > There is *nothing* incorrect in /proc/interrupt. If anything, changing > the string *is* an ABI change, for no good reason. I've minimized the modification to fix the problem, please have a look: https://lore.kernel.org/linux-riscv/20220130135634.1213301-3-guoren@kernel.org/T/#u > > M. > > -- > Without deviation from the norm, progress is not possible. -- Best Regards Guo Ren ML: https://lore.kernel.org/linux-csky/
diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index 259065d271ef..245655928076 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -172,7 +172,7 @@ static void plic_irq_eoi(struct irq_data *d) } } -static struct irq_chip plic_chip = { +static struct irq_chip sifive_plic_chip = { .name = "SiFive PLIC", .irq_mask = plic_irq_mask, .irq_unmask = plic_irq_unmask, @@ -182,12 +182,24 @@ static struct irq_chip plic_chip = { #endif }; +static struct irq_chip thead_plic_chip = { + .name = "T-Head PLIC", + .irq_mask = plic_irq_mask, + .irq_unmask = plic_irq_unmask, + .irq_eoi = plic_irq_eoi, +#ifdef CONFIG_SMP + .irq_set_affinity = plic_set_affinity, +#endif +}; + +static struct irq_chip *def_plic_chip = &sifive_plic_chip; + static int plic_irqdomain_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hwirq) { struct plic_priv *priv = d->host_data; - irq_domain_set_info(d, irq, hwirq, &plic_chip, d->host_data, + irq_domain_set_info(d, irq, hwirq, def_plic_chip, d->host_data, handle_fasteoi_irq, NULL, NULL); irq_set_noprobe(irq); irq_set_affinity(irq, &priv->lmask); @@ -396,5 +408,14 @@ static int __init plic_init(struct device_node *node, return error; } +static int __init thead_c900_plic_init(struct device_node *node, + struct device_node *parent) +{ + def_plic_chip = &thead_plic_chip; + + return plic_init(node, parent); +} + IRQCHIP_DECLARE(sifive_plic, "sifive,plic-1.0.0", plic_init); IRQCHIP_DECLARE(riscv_plic0, "riscv,plic0", plic_init); /* for legacy systems */ +IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", thead_c900_plic_init);