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* [rng] Check for functioning RTC interruptMichael Brown2016-07-101-0/+56
| | | | | | | | | | | | | | | | | | | | | On some platforms (observed in a small subset of Microsoft Azure (Hyper-V) virtual machines), the RTC appears to be incapable of generating an interrupt via the legacy PIC. The RTC status registers show that a periodic interrupt has been asserted, but the PIC IRR shows that IRQ8 remains inactive. On such systems, iPXE will currently freeze during the "iPXE initialising devices..." message. Work around this problem by checking that RTC interrupts are being raised before returning from rtc_entropy_enable(). If no interrupt is seen within 100ms, then we assume that the RTC interrupt mechanism is broken. In these circumstances, iPXE will continue to initialise but any subsequent attempt to generate entropy will fail. In particular, HTTPS connections will fail with an error indicating that no entropy is available. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [bios] Make uses of REAL_CODE() and PHYS_CODE() 64-bit cleanMichael Brown2016-02-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | On a 64-bit CPU, any modification of a register by 32-bit or 16-bit code will destroy the invisible upper 32 bits of the corresponding 64-bit register. For example: a 32-bit "pushl %eax" followed by a "popl %eax" will zero the upper half of %rax. This differs from the treatment of upper halves of 32-bit registers by 16-bit code: a "pushw %ax" followed by a "popw %ax" will leave the upper 16 bits of %eax unmodified. Inline assembly generated using REAL_CODE() or PHYS_CODE() will therefore have to preserve the upper halves of all registers, to avoid clobbering registers that gcc expects to be preserved. Output operands from REAL_CODE() and PHYS_CODE() assembly may therefore contain undefined values in the upper 32 bits. Fix by using explicit variable widths (e.g. uint32_t) for non-discarded output operands, to ensure that undefined values in the upper 32 bits of 64-bit registers are ignored. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [bios] Add bin-x86_64-pcbios build platformMichael Brown2016-02-161-0/+199
Move most arch/i386 files to arch/x86, and adjust the contents of the Makefiles and the include/bits/*.h headers to reflect the new locations. This patch makes no substantive code changes, as can be seen using a rename-aware diff (e.g. "git show -M5"). This patch does not make the pcbios platform functional for x86_64; it merely allows it to compile without errors. Signed-off-by: Michael Brown <mcb30@ipxe.org>