Dear Scott Wood,
Then assign struct soc *soc = (struct soc *)0;
One snag you might hit is that dereferencing a NULL pointer is undefined, and some versions of GCC assume you won't do this when optimizing. Not sure if this simple usage would be affected (it seems to mainly be an issue when comparing a pointer to NULL after dereferencing), and -fno-delete-null-pointer-checks may help.
Its just an idea anyway...
Certainly the 1st way I proposed is the easiest to go: #define BLOCK_BASE_ADDR 0xsomething block_t *block = (block_t *)BLOCK_BASE_ADDR;
Whats a IOCCC?
The International Obfuscated C Code Contest, possibly a more appropriate venue for code that defines a 4GB struct. :-)
In that case I am quite sure the current AT91 way of defining the hardware addresses to the drivers already qualifies for that ;) (Try to follow the definition of SPI0_BASE...)
arch-at91/memory_map.h: ... #ifndef __ASM_ARM_ARCH_MEMORYMAP_H__ #define __ASM_ARM_ARCH_MEMORYMAP_H__
#include <asm/arch/hardware.h>
#define USART0_BASE AT91_USART0 #define USART1_BASE AT91_USART1 #define USART2_BASE AT91_USART2 #define USART3_BASE (AT91_BASE_SYS + AT91_DBGU) #define SPI0_BASE AT91_BASE_SPI #define SPI1_BASE AT91_BASE_SPI1
#endif /* __ASM_ARM_ARCH_MEMORYMAP_H__ */ ...
arch-at91/harware.h: ... #if defined(CONFIG_AT91RM9200) #include <asm/arch-at91/at91rm9200.h> #elif defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9G20) #include <asm/arch/at91sam9260.h> #define AT91_BASE_SPI AT91SAM9260_BASE_SPI0 #define AT91_BASE_SPI1 AT91SAM9260_BASE_SPI1 #define AT91_ID_UHP AT91SAM9260_ID_UHP #define AT91_PMC_UHP AT91SAM926x_PMC_UHP #define AT91_BASE_MMCI AT91SAM9260_BASE_MCI #elif defined(CONFIG_AT91SAM9261) || defined(CONFIG_AT91SAM9G10) #include <asm/arch/at91sam9261.h> #define AT91_BASE_SPI AT91SAM9261_BASE_SPI0 #define AT91_ID_UHP AT91SAM9261_ID_UHP #define AT91_PMC_UHP AT91SAM926x_PMC_UHP #elif defined(CONFIG_AT91SAM9263) ...
arch-at91/at91sam9260.h: ... #ifdef CONFIG_AT91_LEGACY
/* * User Peripheral physical base addresses. */ #define AT91SAM9260_BASE_TCB0 0xfffa0000 #define AT91SAM9260_BASE_TC0 0xfffa0000 #define AT91SAM9260_BASE_TC1 0xfffa0040 #define AT91SAM9260_BASE_TC2 0xfffa0080 #define AT91SAM9260_BASE_UDP 0xfffa4000 #define AT91SAM9260_BASE_MCI 0xfffa8000 #define AT91SAM9260_BASE_TWI 0xfffac000 #define AT91SAM9260_BASE_US0 0xfffb0000 #define AT91SAM9260_BASE_US1 0xfffb4000 #define AT91SAM9260_BASE_US2 0xfffb8000 #define AT91SAM9260_BASE_SSC 0xfffbc000 #define AT91SAM9260_BASE_ISI 0xfffc0000 #define AT91SAM9260_BASE_EMAC 0xfffc4000 #define AT91SAM9260_BASE_SPI0 0xfffc8000 #define AT91SAM9260_BASE_SPI1 0xfffcc000 #define AT91SAM9260_BASE_US3 0xfffd0000 #define AT91SAM9260_BASE_US4 0xfffd4000 #define AT91SAM9260_BASE_US5 0xfffd8000 #define AT91SAM9260_BASE_TCB1 0xfffdc000 #define AT91SAM9260_BASE_TC3 0xfffdc000 #define AT91SAM9260_BASE_TC4 0xfffdc040 #define AT91SAM9260_BASE_TC5 0xfffdc080 #define AT91SAM9260_BASE_ADC 0xfffe0000 #define AT91_BASE_SYS 0xffffe800 ...
arch-at91/at91sam9261.h: ... #ifdef CONFIG_AT91_LEGACY
/* * User Peripheral physical base addresses. */ #define AT91SAM9261_BASE_TCB0 0xfffa0000 #define AT91SAM9261_BASE_TC0 0xfffa0000 #define AT91SAM9261_BASE_TC1 0xfffa0040 #define AT91SAM9261_BASE_TC2 0xfffa0080 #define AT91SAM9261_BASE_UDP 0xfffa4000 #define AT91SAM9261_BASE_MCI 0xfffa8000 #define AT91SAM9261_BASE_TWI 0xfffac000 #define AT91SAM9261_BASE_US0 0xfffb0000 #define AT91SAM9261_BASE_US1 0xfffb4000 #define AT91SAM9261_BASE_US2 0xfffb8000 #define AT91SAM9261_BASE_SSC0 0xfffbc000 #define AT91SAM9261_BASE_SSC1 0xfffc0000 #define AT91SAM9261_BASE_SSC2 0xfffc4000 #define AT91SAM9261_BASE_SPI0 0xfffc8000 #define AT91SAM9261_BASE_SPI1 0xfffcc000 #define AT91_BASE_SYS 0xffffea00 ...
isn't that obfuscated enough?
Reinhard