haraldwolff/qemu-patch-raspberry4
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qemu-patch-raspberry4/pc-bios/optionrom/multiboot_dma.S

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optionrom: add a DMA-enabled multiboot ROM Add a new option rom for the multiboot loader, using DMA transfers to copy data instead of "rep insb". This significantly lowers QEMU's startup latency by a factor of about 40, for example, going from 30sec to 0.8sec when loading modules of 120MB in size. Signed-off-by: Marcus Hähnel <marcus.haehnel@kernkonzept.com> Signed-off-by: Adam Lackorzynski <adam@l4re.org> [Modified to keep the non-DMA code depending on #ifdef USE_FW_CFG_DMA; do not write below stack. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-20 14:55:04 +02:00
#define USE_FW_CFG_DMA 1
#include "multiboot.S"
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