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cosmetic updates to comments

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This commit is contained in:
Gregory Nutt 2014-03-30 10:25:01 -06:00
parent 4410deb8b6
commit 8e919137b2
1 changed files with 10 additions and 6 deletions
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16
arch/arm/src/sama5/sam_boot.c
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@ -135,15 +135,19 @@ static const struct section_mapping_s section_mapping[] =
* mapping to map the boot region at 0x0000:0000 to virtual address
* 0x0000:00000
*
* The first level bootloader is supposed to provide the AXI MATRIX
* mapping for us at boot time base on the state of the BMS pin. However,
* I have found that in the test environments that I use, I cannot always
* be assured of that physical address mapping.
* When executing from NOR FLASH, the first level bootloader is supposed
* to provide the AXI MATRIX mapping for us at boot time base on the state
* of the BMS pin. However, I have found that in the test environments
* that I use, I cannot always be assured of that physical address mapping.
*
* So we do both here. If we are executing from FLASH, then we provide
* the MMU to map the physical address of FLASH to address 0x0000:0000;
* if we are executing from the internal SRAM, then we trust the bootload
* to setup the AXI MATRIX mapping.
*
* If we are executing out of ISRAM, then the SAMA5 primary bootloader
* probably copied us into ISRAM. If we are executing from external
* SDRAM, then a secondary bootloader must have loaded us into SDRAM. In
* either case we trust the bootloader to setup the AXI MATRIX mapping on
* our behalf.
*/
#if defined(CONFIG_ARCH_LOWVECTORS) && !defined(CONFIG_SAMA5_BOOT_ISRAM) && \