[PATCH 02/36] ARM: s3c: simplify mach/io.h

From: Arnd Bergmann
Date: Thu Oct 10 2019 - 16:31:15 EST


s3c24xx has a custom implementation of the inb/outb family of I/O
accessors, implementing both general register access and ISA I/O port
through a multiplexer.

As far as I can tell, the first case has never been needed, and certainly
is not used now, as drivers only use inb/outb to actually driver ISA or
PCI port I/O.

Similarly, the special ISA support is limited to a single machine, the
Simtec Electronics BAST (EB2410ITX) with its PC/104 expansion connector,
all other machines could simply use the generic implementation from
asm/io.h that expects a single memory-mapped address range for byte,
word and dword access. As no other machines besides BAST actually selects
CONFIG_ISA, this is likely not even necessary.

As a cleanup, remove suport for the non-ISA access from the helpers,
and make the ISA access use the virtual address window that we use
elsewhere for PCI I/O ports. In configurations without the BAST machine,
this now falls back on the generic implementation from asm/io.h, but
the mach/io.h header is still relied on to include a number of other
header files implicitly.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/arm/mach-s3c24xx/include/mach/io.h | 209 +++----------------
arch/arm/plat-samsung/include/plat/map-s3c.h | 10 +-
2 files changed, 26 insertions(+), 193 deletions(-)

diff --git a/arch/arm/mach-s3c24xx/include/mach/io.h b/arch/arm/mach-s3c24xx/include/mach/io.h
index f960e6d10114..3e8bff26cdd5 100644
--- a/arch/arm/mach-s3c24xx/include/mach/io.h
+++ b/arch/arm/mach-s3c24xx/include/mach/io.h
@@ -12,201 +12,40 @@

#include <mach/hardware.h>

-#define IO_SPACE_LIMIT 0xffffffff

/*
- * We use two different types of addressing - PC style addresses, and ARM
- * addresses. PC style accesses the PC hardware with the normal PC IO
- * addresses, eg 0x3f8 for serial#1. ARM addresses are above A28
- * and are translated to the start of IO. Note that all addresses are
- * not shifted left!
+ * ISA style IO, for each machine to sort out mappings for,
+ * if it implements it. We reserve two 16M regions for ISA,
+ * so the PC/104 can use separate addresses for 8-bit and
+ * 16-bit port I/O.
*/
+#define PCIO_BASE S3C_ADDR(0x02000000)
+#define IO_SPACE_LIMIT 0x00ffffff
+#define S3C24XX_VA_ISA_WORD (PCIO_BASE)
+#define S3C24XX_VA_ISA_BYTE (PCIO_BASE + 0x01000000)

-#define __PORT_PCIO(x) ((x) < (1<<28))
+#ifdef CONFIG_ISA

-#define PCIO_BASE (S3C24XX_VA_ISA_WORD)
-#define PCIO_BASE_b (S3C24XX_VA_ISA_BYTE)
-#define PCIO_BASE_w (S3C24XX_VA_ISA_WORD)
-#define PCIO_BASE_l (S3C24XX_VA_ISA_WORD)
-/*
- * Dynamic IO functions - let the compiler
- * optimize the expressions
- */
-
-#define DECLARE_DYN_OUT(sz,fnsuffix,instr) \
-static inline void __out##fnsuffix (unsigned int val, unsigned int port) \
-{ \
- unsigned long temp; \
- __asm__ __volatile__( \
- "cmp %2, #(1<<28)\n\t" \
- "mov %0, %2\n\t" \
- "addcc %0, %0, %3\n\t" \
- "str" instr " %1, [%0, #0 ] @ out" #fnsuffix \
- : "=&r" (temp) \
- : "r" (val), "r" (port), "Ir" (PCIO_BASE_##fnsuffix) \
- : "cc"); \
-}
-
-
-#define DECLARE_DYN_IN(sz,fnsuffix,instr) \
-static inline unsigned sz __in##fnsuffix (unsigned int port) \
-{ \
- unsigned long temp, value; \
- __asm__ __volatile__( \
- "cmp %2, #(1<<28)\n\t" \
- "mov %0, %2\n\t" \
- "addcc %0, %0, %3\n\t" \
- "ldr" instr " %1, [%0, #0 ] @ in" #fnsuffix \
- : "=&r" (temp), "=r" (value) \
- : "r" (port), "Ir" (PCIO_BASE_##fnsuffix) \
- : "cc"); \
- return (unsigned sz)value; \
-}
+#define inb(p) readb(S3C24XX_VA_ISA_BYTE + (p))
+#define inw(p) readw(S3C24XX_VA_ISA_WORD + (p))
+#define inl(p) readl(S3C24XX_VA_ISA_WORD + (p))

-static inline void __iomem *__ioaddr (unsigned long port)
-{
- return __PORT_PCIO(port) ? (PCIO_BASE + port) : (void __iomem *)port;
-}
+#define outb(v,p) writeb((v), S3C24XX_VA_ISA_BYTE + (p))
+#define outw(v,p) writew((v), S3C24XX_VA_ISA_WORD + (p))
+#define outl(v,p) writel((v), S3C24XX_VA_ISA_WORD + (p))

-#define DECLARE_IO(sz,fnsuffix,instr) \
- DECLARE_DYN_IN(sz,fnsuffix,instr) \
- DECLARE_DYN_OUT(sz,fnsuffix,instr)
+#define insb(p,d,l) readsb(S3C24XX_VA_ISA_BYTE + (p),d,l)
+#define insw(p,d,l) readsw(S3C24XX_VA_ISA_WORD + (p),d,l)
+#define insl(p,d,l) readsl(S3C24XX_VA_ISA_WORD + (p),d,l)

-DECLARE_IO(char,b,"b")
-DECLARE_IO(short,w,"h")
-DECLARE_IO(int,l,"")
+#define outsb(p,d,l) writesb(S3C24XX_VA_ISA_BYTE + (p),d,l)
+#define outsw(p,d,l) writesw(S3C24XX_VA_ISA_WORD + (p),d,l)
+#define outsl(p,d,l) writesl(S3C24XX_VA_ISA_WORD + (p),d,l)

-#undef DECLARE_IO
-#undef DECLARE_DYN_IN
-
-/*
- * Constant address IO functions
- *
- * These have to be macros for the 'J' constraint to work -
- * +/-4096 immediate operand.
- */
-#define __outbc(value,port) \
-({ \
- if (__PORT_PCIO((port))) \
- __asm__ __volatile__( \
- "strb %0, [%1, %2] @ outbc" \
- : : "r" (value), "r" (PCIO_BASE), "Jr" ((port))); \
- else \
- __asm__ __volatile__( \
- "strb %0, [%1, #0] @ outbc" \
- : : "r" (value), "r" ((port))); \
-})
+#else

-#define __inbc(port) \
-({ \
- unsigned char result; \
- if (__PORT_PCIO((port))) \
- __asm__ __volatile__( \
- "ldrb %0, [%1, %2] @ inbc" \
- : "=r" (result) : "r" (PCIO_BASE), "Jr" ((port))); \
- else \
- __asm__ __volatile__( \
- "ldrb %0, [%1, #0] @ inbc" \
- : "=r" (result) : "r" ((port))); \
- result; \
-})
+#define __io(x) (PCIO_BASE + (x))

-#define __outwc(value,port) \
-({ \
- unsigned long v = value; \
- if (__PORT_PCIO((port))) { \
- if ((port) < 256 && (port) > -256) \
- __asm__ __volatile__( \
- "strh %0, [%1, %2] @ outwc" \
- : : "r" (v), "r" (PCIO_BASE), "Jr" ((port))); \
- else if ((port) > 0) \
- __asm__ __volatile__( \
- "strh %0, [%1, %2] @ outwc" \
- : : "r" (v), \
- "r" (PCIO_BASE + ((port) & ~0xff)), \
- "Jr" (((port) & 0xff))); \
- else \
- __asm__ __volatile__( \
- "strh %0, [%1, #0] @ outwc" \
- : : "r" (v), \
- "r" (PCIO_BASE + (port))); \
- } else \
- __asm__ __volatile__( \
- "strh %0, [%1, #0] @ outwc" \
- : : "r" (v), "r" ((port))); \
-})
-
-#define __inwc(port) \
-({ \
- unsigned short result; \
- if (__PORT_PCIO((port))) { \
- if ((port) < 256 && (port) > -256 ) \
- __asm__ __volatile__( \
- "ldrh %0, [%1, %2] @ inwc" \
- : "=r" (result) \
- : "r" (PCIO_BASE), \
- "Jr" ((port))); \
- else if ((port) > 0) \
- __asm__ __volatile__( \
- "ldrh %0, [%1, %2] @ inwc" \
- : "=r" (result) \
- : "r" (PCIO_BASE + ((port) & ~0xff)), \
- "Jr" (((port) & 0xff))); \
- else \
- __asm__ __volatile__( \
- "ldrh %0, [%1, #0] @ inwc" \
- : "=r" (result) \
- : "r" (PCIO_BASE + ((port)))); \
- } else \
- __asm__ __volatile__( \
- "ldrh %0, [%1, #0] @ inwc" \
- : "=r" (result) : "r" ((port))); \
- result; \
-})
-
-#define __outlc(value,port) \
-({ \
- unsigned long v = value; \
- if (__PORT_PCIO((port))) \
- __asm__ __volatile__( \
- "str %0, [%1, %2] @ outlc" \
- : : "r" (v), "r" (PCIO_BASE), "Jr" ((port))); \
- else \
- __asm__ __volatile__( \
- "str %0, [%1, #0] @ outlc" \
- : : "r" (v), "r" ((port))); \
-})
-
-#define __inlc(port) \
-({ \
- unsigned long result; \
- if (__PORT_PCIO((port))) \
- __asm__ __volatile__( \
- "ldr %0, [%1, %2] @ inlc" \
- : "=r" (result) : "r" (PCIO_BASE), "Jr" ((port))); \
- else \
- __asm__ __volatile__( \
- "ldr %0, [%1, #0] @ inlc" \
- : "=r" (result) : "r" ((port))); \
- result; \
-})
-
-#define __ioaddrc(port) ((__PORT_PCIO(port) ? PCIO_BASE + (port) : (void __iomem *)0 + (port)))
-
-#define inb(p) (__builtin_constant_p((p)) ? __inbc(p) : __inb(p))
-#define inw(p) (__builtin_constant_p((p)) ? __inwc(p) : __inw(p))
-#define inl(p) (__builtin_constant_p((p)) ? __inlc(p) : __inl(p))
-#define outb(v,p) (__builtin_constant_p((p)) ? __outbc(v,p) : __outb(v,p))
-#define outw(v,p) (__builtin_constant_p((p)) ? __outwc(v,p) : __outw(v,p))
-#define outl(v,p) (__builtin_constant_p((p)) ? __outlc(v,p) : __outl(v,p))
-#define __ioaddr(p) (__builtin_constant_p((p)) ? __ioaddr(p) : __ioaddrc(p))
-
-#define insb(p,d,l) __raw_readsb(__ioaddr(p),d,l)
-#define insw(p,d,l) __raw_readsw(__ioaddr(p),d,l)
-#define insl(p,d,l) __raw_readsl(__ioaddr(p),d,l)
-
-#define outsb(p,d,l) __raw_writesb(__ioaddr(p),d,l)
-#define outsw(p,d,l) __raw_writesw(__ioaddr(p),d,l)
-#define outsl(p,d,l) __raw_writesl(__ioaddr(p),d,l)
+#endif

#endif
diff --git a/arch/arm/plat-samsung/include/plat/map-s3c.h b/arch/arm/plat-samsung/include/plat/map-s3c.h
index 4244acbf4b65..bf247d836684 100644
--- a/arch/arm/plat-samsung/include/plat/map-s3c.h
+++ b/arch/arm/plat-samsung/include/plat/map-s3c.h
@@ -9,6 +9,8 @@
#ifndef __ASM_PLAT_MAP_S3C_H
#define __ASM_PLAT_MAP_S3C_H __FILE__

+#include <mach/map.h>
+
#define S3C24XX_VA_IRQ S3C_VA_IRQ
#define S3C24XX_VA_MEMCTRL S3C_VA_MEM
#define S3C24XX_VA_UART S3C_VA_UART
@@ -45,16 +47,8 @@

#define S3C_VA_USB_HSPHY S3C64XX_VA_USB_HSPHY

-/*
- * ISA style IO, for each machine to sort out mappings for,
- * if it implements it. We reserve two 16M regions for ISA.
- */
-
#define S3C2410_ADDR(x) S3C_ADDR(x)

-#define S3C24XX_VA_ISA_WORD S3C2410_ADDR(0x02000000)
-#define S3C24XX_VA_ISA_BYTE S3C2410_ADDR(0x03000000)
-
/* deal with the registers that move under the 2412/2413 */

#if defined(CONFIG_CPU_S3C2412)
--
2.20.0