| Message ID | 1420857290-8373-8-git-send-email-robh@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Sat, Jan 10, 2015 at 3:34 AM, Rob Herring <robh@kernel.org> wrote: > Convert the integrator PCI driver to use the generic config access > functions. > > This changes accesses from __raw_readX/__raw_writeX to readX/writeX > variants. Just as good. > The spinlock is removed because it is unnecessary. The config > read and write functions are already protected with a spinlock and no > access can occur during the .pre_init function. > > Signed-off-by: Rob Herring <robh@kernel.org> > Cc: Russell King <linux@arm.linux.org.uk> > Cc: Linus Walleij <linus.walleij@linaro.org> > Cc: linux-arm-kernel@lists.infradead.org I trust that you do the right thing I guess... Acked-by: Linus Walleij <linus.walleij@linaro.org> > static int v3_read_config(struct pci_bus *bus, unsigned int devfn, int where, > int size, u32 *val) > { > - addr = v3_open_config_window(bus, devfn, where); > + int ret = pci_generic_config_read(bus, devfn, where, size, val); > v3_close_config_window(); > + return ret; > } > > static int v3_write_config(struct pci_bus *bus, unsigned int devfn, int where, > int size, u32 val) > { > + int ret = pci_generic_config_write(bus, devfn, where, size, val); > v3_close_config_window(); > - raw_spin_unlock_irqrestore(&v3_lock, flags); > + return ret; > } > > static struct pci_ops pci_v3_ops = { > + .map_bus = v3_open_config_window, > .read = v3_read_config, > .write = v3_write_config, So .map_bus is called before every .read/.write operation I take it. Wouldn't it be proper to call the v3_close_config_window() from a matching .unmap_bus() callback for symmetry? Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Saturday 10 January 2015 22:40:22 Linus Walleij wrote: > > static int v3_read_config(struct pci_bus *bus, unsigned int devfn, int where, > > int size, u32 *val) > > { > > - addr = v3_open_config_window(bus, devfn, where); > > + int ret = pci_generic_config_read(bus, devfn, where, size, val); > > v3_close_config_window(); > > + return ret; > > } > > > > static int v3_write_config(struct pci_bus *bus, unsigned int devfn, int where, > > int size, u32 val) > > { > > + int ret = pci_generic_config_write(bus, devfn, where, size, val); > > v3_close_config_window(); > > - raw_spin_unlock_irqrestore(&v3_lock, flags); > > + return ret; > > } > > > > static struct pci_ops pci_v3_ops = { > > + .map_bus = v3_open_config_window, > > .read = v3_read_config, > > .write = v3_write_config, > > So .map_bus is called before every .read/.write operation I take it. > > Wouldn't it be proper to call the v3_close_config_window() from a > matching .unmap_bus() callback for symmetry? It would be nicer for integrator but useless for anything else, so I'd vote for leaving it the way Rob posted. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Jan 10, 2015 at 10:53 PM, Arnd Bergmann <arnd@arndb.de> wrote: > On Saturday 10 January 2015 22:40:22 Linus Walleij wrote: >> > static int v3_read_config(struct pci_bus *bus, unsigned int devfn, int where, >> > int size, u32 *val) >> > { >> > - addr = v3_open_config_window(bus, devfn, where); >> > + int ret = pci_generic_config_read(bus, devfn, where, size, val); >> > v3_close_config_window(); >> > + return ret; >> > } >> > >> > static int v3_write_config(struct pci_bus *bus, unsigned int devfn, int where, >> > int size, u32 val) >> > { >> > + int ret = pci_generic_config_write(bus, devfn, where, size, val); >> > v3_close_config_window(); >> > - raw_spin_unlock_irqrestore(&v3_lock, flags); >> > + return ret; >> > } >> > >> > static struct pci_ops pci_v3_ops = { >> > + .map_bus = v3_open_config_window, >> > .read = v3_read_config, >> > .write = v3_write_config, >> >> So .map_bus is called before every .read/.write operation I take it. >> >> Wouldn't it be proper to call the v3_close_config_window() from a >> matching .unmap_bus() callback for symmetry? > > It would be nicer for integrator but useless for anything else, so > I'd vote for leaving it the way Rob posted. OK I buy that, throw in a comment about it in the code if there is some time for iterating the patch. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/mach-integrator/pci_v3.c b/arch/arm/mach-integrator/pci_v3.c index c186a17..dc7782f 100644 --- a/arch/arm/mach-integrator/pci_v3.c +++ b/arch/arm/mach-integrator/pci_v3.c @@ -356,7 +356,6 @@ static u64 pre_mem_pci_sz; * 7:2 register number * */ -static DEFINE_RAW_SPINLOCK(v3_lock); #undef V3_LB_BASE_PREFETCH #define V3_LB_BASE_PREFETCH 0 @@ -457,67 +456,21 @@ static void v3_close_config_window(void) static int v3_read_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) { - void __iomem *addr; - unsigned long flags; - u32 v; - - raw_spin_lock_irqsave(&v3_lock, flags); - addr = v3_open_config_window(bus, devfn, where); - - switch (size) { - case 1: - v = __raw_readb(addr); - break; - - case 2: - v = __raw_readw(addr); - break; - - default: - v = __raw_readl(addr); - break; - } - + int ret = pci_generic_config_read(bus, devfn, where, size, val); v3_close_config_window(); - raw_spin_unlock_irqrestore(&v3_lock, flags); - - *val = v; - return PCIBIOS_SUCCESSFUL; + return ret; } static int v3_write_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) { - void __iomem *addr; - unsigned long flags; - - raw_spin_lock_irqsave(&v3_lock, flags); - addr = v3_open_config_window(bus, devfn, where); - - switch (size) { - case 1: - __raw_writeb((u8)val, addr); - __raw_readb(addr); - break; - - case 2: - __raw_writew((u16)val, addr); - __raw_readw(addr); - break; - - case 4: - __raw_writel(val, addr); - __raw_readl(addr); - break; - } - + int ret = pci_generic_config_write(bus, devfn, where, size, val); v3_close_config_window(); - raw_spin_unlock_irqrestore(&v3_lock, flags); - - return PCIBIOS_SUCCESSFUL; + return ret; } static struct pci_ops pci_v3_ops = { + .map_bus = v3_open_config_window, .read = v3_read_config, .write = v3_write_config, }; @@ -672,8 +625,6 @@ static void __init pci_v3_preinit(void) hook_fault_code(8, v3_pci_fault, SIGBUS, 0, "external abort on non-linefetch"); hook_fault_code(10, v3_pci_fault, SIGBUS, 0, "external abort on non-linefetch"); - raw_spin_lock_irqsave(&v3_lock, flags); - /* * Unlock V3 registers, but only if they were previously locked. */ @@ -736,8 +687,6 @@ static void __init pci_v3_preinit(void) v3_writew(V3_LB_CFG, v3_readw(V3_LB_CFG) | (1 << 10)); v3_writeb(V3_LB_IMASK, 0x28); __raw_writel(3, ap_syscon_base + INTEGRATOR_SC_PCIENABLE_OFFSET); - - raw_spin_unlock_irqrestore(&v3_lock, flags); } static void __init pci_v3_postinit(void)
Convert the integrator PCI driver to use the generic config access functions. This changes accesses from __raw_readX/__raw_writeX to readX/writeX variants. The spinlock is removed because it is unnecessary. The config read and write functions are already protected with a spinlock and no access can occur during the .pre_init function. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: linux-arm-kernel@lists.infradead.org --- arch/arm/mach-integrator/pci_v3.c | 61 ++++----------------------------------- 1 file changed, 5 insertions(+), 56 deletions(-)