Hi Finn, thanks for your review! On 3/06/21 8:23 pm, Finn Thain wrote:
I noticed :-) Fat-fingered the commit in a hurry (and didn't run checkpatch).On Wed, 2 Jun 2021, Michael Schmitz wrote:Current io_mm.h uses address translation and ROM port IO primitives when port addresses are below 1024, and raw untranslated MMIO IO primitives else when CONFIG_ATARI_ROM_ISA is set. This is done regardless of the m68k machine type a multi-platform kernel runs on. As a consequence, the Q40 IDE driver in multiplatform kernels cannot work. Conversely, the Atari IDE driver uses wrong address translation if a multiplatform Q40 and Atari kernel does _not_ set CONFIG_ATARI_ROM_ISA. Replace MMIO by ISA IO primitives for addresses > 1024 (if isa_type is ISA_TYPE_ENEC), and change the ISA address translation used for Atari to a no-op for those addresses. Switch readb()/writeb() and readw()/writew() to their ISA equivalents also. Change the address translation functions to return the identity translation if CONFIG_ATARI_ROM_ISA is not defined, and set MULTI_ISA for kernels where Q40 and Atari are both configured so this can actually work (isa_type set to Q40 at compile time else).Thanks, this does fix the problem I had with CONFIG_ATARI && CONFIG_ISA.Signed-off-by: Michael Schmity <schmitzmic@xxxxxxxxx>Checkpatch points out a typo here.
I wasn't sure what to use as commit ID to be fixed ... Looks like 84b16b7b0d5c818fadc731a69965dc76dce0c91e is the one to blame. Hmm - I thought that code was older than that...Also, I think this should get a 'Fixes' tag so it will be backported.
--- arch/m68k/include/asm/io_mm.h | 64 +++++++++++++++++++++++++++---------------- 1 file changed, 40 insertions(+), 24 deletions(-) diff --git a/arch/m68k/include/asm/io_mm.h b/arch/m68k/include/asm/io_mm.h index d41fa48..2275e54 100644 --- a/arch/m68k/include/asm/io_mm.h +++ b/arch/m68k/include/asm/io_mm.h @@ -52,7 +52,11 @@ #define Q40_ISA_MEM_B(madr) (q40_isa_mem_base+1+4*((unsigned long)(madr))) #define Q40_ISA_MEM_W(madr) (q40_isa_mem_base+ 4*((unsigned long)(madr)))+#ifdef CONFIG_ATARI+#define MULTI_ISA 1 +#else #define MULTI_ISA 0 +#endif /* Atari */ #endif /* Q40 */I have to wonder whether there is a nice simple definition for MULTI_ISA.
As I understand it, MULTI_ISA means that different byte orders and/or different address translations need to be used in the same kernel, so all that cannot be decided at build time.
As long as there is only a single platform that will use this code (ISA only used on a single platform, and neither Atari IDE nor EtherNEC used), MULTI_ISA is not needed.
If we have Kconfig symbols for 'single platform only', and 'multi-platform ISA use', that might be shorter to write and easier to understand. Geert?
Such a definition would make this file a lot more easily understood. Maybe that flag could be implemented as a Kconfig symbol. I guess that's out of scope though.
That Kconfig symbol would best sit in Kconfig.machine but have to be aware of definitions in a number of driver Kconfigs. Haven't tried if that works. But I agree it is out of scope for now.
The question then becomes - should I move the MULTI_ISA definitions out of the Q40 branch and out of the later Amiga Gayle PCMCIA branch to the head of the file and add a comment explaining the rationale? Too much churn for now?
#ifdef CONFIG_AMIGA_PCMCIA @@ -135,9 +139,12 @@ static inline u8 __iomem *isa_itb(unsigned long addr) case ISA_TYPE_AG: return (u8 __iomem *)AG_ISA_IO_B(addr); #endif #ifdef CONFIG_ATARI_ROM_ISA - case ISA_TYPE_ENEC: return (u8 __iomem *)ENEC_ISA_IO_B(addr); + case ISA_TYPE_ENEC: if (addr < 1024) + return (u8 __iomem *)ENEC_ISA_IO_B(addr); + else + return (u8 __iomem *)(addr);There is some trailing whitespace added here that 'git am' complains about. Also, I think a 'fallthrough' statement would be better than adding a new else branch that duplicates the new default case below.
I'm still unsure whether changing the default branch for the sake of fixing Atari behaviour is a sane idea - I was hoping for comments either way.
But if it's changed, you are correct that having the control flow fall through instead of taking a redundant else branch is better.
Essentially, changing that hunk to #ifdef CONFIG_ATARI_ROM_ISA - case ISA_TYPE_ENEC: return (u8 __iomem *)ENEC_ISA_IO_B(addr); + case ISA_TYPE_ENEC: if (addr < 1024) + return (u8 __iomem *)ENEC_ISA_IO_B(addr); here (and elsewhere below)? Cheers, Michael
#endif - default: return NULL; /* avoid warnings, just in case */ + default: return (u8 __iomem *)(addr); /* avoid warnings, just in case */ } } static inline u16 __iomem *isa_itw(unsigned long addr) @@ -151,9 +158,12 @@ static inline u16 __iomem *isa_itw(unsigned long addr) case ISA_TYPE_AG: return (u16 __iomem *)AG_ISA_IO_W(addr); #endif #ifdef CONFIG_ATARI_ROM_ISA - case ISA_TYPE_ENEC: return (u16 __iomem *)ENEC_ISA_IO_W(addr); + case ISA_TYPE_ENEC: if (addr < 1024) + return (u16 __iomem *)ENEC_ISA_IO_W(addr); + else + return (u16 __iomem *)(addr); #endif - default: return NULL; /* avoid warnings, just in case */ + default: return (u16 __iomem *)(addr); /* avoid warnings, just in case */Same here.} } static inline u32 __iomem *isa_itl(unsigned long addr) @@ -177,9 +187,12 @@ static inline u8 __iomem *isa_mtb(unsigned long addr) case ISA_TYPE_AG: return (u8 __iomem *)addr; #endif #ifdef CONFIG_ATARI_ROM_ISA - case ISA_TYPE_ENEC: return (u8 __iomem *)ENEC_ISA_MEM_B(addr); + case ISA_TYPE_ENEC: if (addr < 1024) + return (u8 __iomem *)ENEC_ISA_MEM_B(addr); + else + return (u8 __iomem *)(addr); #endif - default: return NULL; /* avoid warnings, just in case */ + default: return (u8 __iomem *)(addr); /* avoid warnings, just in case */And here.} } static inline u16 __iomem *isa_mtw(unsigned long addr) @@ -193,9 +206,12 @@ static inline u16 __iomem *isa_mtw(unsigned long addr) case ISA_TYPE_AG: return (u16 __iomem *)addr; #endif #ifdef CONFIG_ATARI_ROM_ISA - case ISA_TYPE_ENEC: return (u16 __iomem *)ENEC_ISA_MEM_W(addr); + case ISA_TYPE_ENEC: if (addr < 1024) + return (u16 __iomem *)ENEC_ISA_MEM_W(addr); + else + return (u16 __iomem *)(addr); #endif - default: return NULL; /* avoid warnings, just in case */ + default: return (u16 __iomem *)(addr); /* avoid warnings, just in case */And here.} }@@ -344,31 +360,31 @@ static inline void isa_delay(void)* ROM port ISA and everything else regular ISA for IDE. read,write defined * below. */ -#define inb(port) ((port) < 1024 ? isa_rom_inb(port) : in_8(port)) -#define inb_p(port) ((port) < 1024 ? isa_rom_inb_p(port) : in_8(port)) -#define inw(port) ((port) < 1024 ? isa_rom_inw(port) : in_le16(port)) -#define inw_p(port) ((port) < 1024 ? isa_rom_inw_p(port) : in_le16(port)) +#define inb(port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_inb(port) : isa_inb(port)) +#define inb_p(port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_inb_p(port) : isa_inb_p(port)) +#define inw(port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_inw(port) : isa_inw(port)) +#define inw_p(port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_inw_p(port) : isa_inw_p(port)) #define inl isa_inl #define inl_p isa_inl_p-#define outb(val, port) ((port) < 1024 ? isa_rom_outb((val), (port)) : out_8((port), (val)))-#define outb_p(val, port) ((port) < 1024 ? isa_rom_outb_p((val), (port)) : out_8((port), (val))) -#define outw(val, port) ((port) < 1024 ? isa_rom_outw((val), (port)) : out_le16((port), (val))) -#define outw_p(val, port) ((port) < 1024 ? isa_rom_outw_p((val), (port)) : out_le16((port), (val))) +#define outb(val, port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_outb((val), (port)) : isa_outb((val), (port))) +#define outb_p(val, port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_outb_p((val), (port)) : isa_outb_p((val), (port))) +#define outw(val, port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_outw((val), (port)) : isa_outw((val), (port))) +#define outw_p(val, port) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_outw_p((val), (port)) : isa_outw_p((val), (port))) #define outl isa_outl #define outl_p isa_outl_p-#define insb(port, buf, nr) ((port) < 1024 ? isa_rom_insb((port), (buf), (nr)) : isa_insb((port), (buf), (nr)))-#define insw(port, buf, nr) ((port) < 1024 ? isa_rom_insw((port), (buf), (nr)) : isa_insw((port), (buf), (nr))) +#define insb(port, buf, nr) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_insb((port), (buf), (nr)) : isa_insb((port), (buf), (nr))) +#define insw(port, buf, nr) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_insw((port), (buf), (nr)) : isa_insw((port), (buf), (nr))) #define insl isa_insl -#define outsb(port, buf, nr) ((port) < 1024 ? isa_rom_outsb((port), (buf), (nr)) : isa_outsb((port), (buf), (nr))) -#define outsw(port, buf, nr) ((port) < 1024 ? isa_rom_outsw((port), (buf), (nr)) : isa_outsw((port), (buf), (nr))) +#define outsb(port, buf, nr) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_outsb((port), (buf), (nr)) : isa_outsb((port), (buf), (nr))) +#define outsw(port, buf, nr) (((port) < 1024 && ISA_TYPE == ISA_TYPE_ENEC) ? isa_rom_outsw((port), (buf), (nr)) : isa_outsw((port), (buf), (nr))) #define outsl isa_outsl-#define readb(addr) in_8(addr)-#define writeb(val, addr) out_8((addr), (val)) -#define readw(addr) in_le16(addr) -#define writew(val, addr) out_le16((addr), (val)) +#define readb isa_readb +#define readw isa_readw +#define writeb isa_writeb +#define writew isa_writew #endif /* CONFIG_ATARI_ROM_ISA */#define readl(addr) in_le32(addr)