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| author | Andrei Gherzan <andrei@gherzan.ro> | 2019-07-24 16:10:40 +0100 |
|---|---|---|
| committer | Andrei Gherzan <andrei@gherzan.ro> | 2019-07-24 16:10:42 +0100 |
| commit | 009049e728d6a7529c853accb3de169fd17b6d5c (patch) | |
| tree | e59e3843b361a7533d6649c98e871ed58cbd6617 | |
| parent | 0d641c8fa918b1c5ecce2cb9918c47bb3c4e1510 (diff) | |
| download | meta-raspberrypi-ag/rpi4-mem.tar.gz | |
raspberrypi4-64.conf: Limit RAM to 3Gag/rpi4-mem
The PCI controller on the Raspberry Pi 4 acts as a DMA controller and can
only address the first 3Gb[1] of the memory space. On 32bit this was
addressed by implementing bouncing buffers[2] but this currently has no
support for arm64. In order to have working USB, as a workaround, we
limit the ram to 3G.
Fixes #446
[1] https://github.com/raspberrypi/linux/issues/3093
[2] https://github.com/raspberrypi/linux/blob/rpi-4.19.y/drivers/pci/controller/pcie-brcmstb-bounce.c
Signed-off-by: Andrei Gherzan <andrei@gherzan.ro>
| -rw-r--r-- | conf/machine/raspberrypi4-64.conf | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/conf/machine/raspberrypi4-64.conf b/conf/machine/raspberrypi4-64.conf index e308577..2455172 100644 --- a/conf/machine/raspberrypi4-64.conf +++ b/conf/machine/raspberrypi4-64.conf | |||
| @@ -31,6 +31,6 @@ KERNEL_IMAGETYPE_UBOOT ?= "Image" | |||
| 31 | KERNEL_IMAGETYPE_DIRECT ?= "Image" | 31 | KERNEL_IMAGETYPE_DIRECT ?= "Image" |
| 32 | KERNEL_BOOTCMD ?= "booti" | 32 | KERNEL_BOOTCMD ?= "booti" |
| 33 | 33 | ||
| 34 | RPI_EXTRA_CONFIG ?= "\n# Force arm in 64bit mode. See: https://github.com/raspberrypi/firmware/issues/1193.\narm_64bit=1" | 34 | RPI_EXTRA_CONFIG ?= "\n# Force arm in 64bit mode. See: https://github.com/raspberrypi/firmware/issues/1193.\narm_64bit=1\n\n# Limit RAM to 3G. See: https://github.com/raspberrypi/linux/issues/3093\ntotal_mem=3072" |
| 35 | 35 | ||
| 36 | ARMSTUB ?= "armstub8-gic.bin" | 36 | ARMSTUB ?= "armstub8-gic.bin" |