The reason for this is to properly support the spi nor chip on the
Jetson Xavier NX module. Prior to this, it would time out on all
transfers and sometimes even trigger a cbb fault, locking up the entire
unit. With this, reading and writing to the flash memory works as
expected.
This also fixes the tegra210-quad spi driver to properly use the dma
memory space instead of the spi controllers. Without this, enabling dma
on the controllers results in mmu faults.
The driver change has only been tested on tegra210 / p3450 and tegra194
/ p3518 as that is the only available test platforms. Tegra234 and
Tegra241 should also be verified. I have p3766 for tegra234, but the
qspi flash memory is firewalled by mb1 on all publicly available
bootloaders, and no other spi devices are part of the devkit.
---
Changes in v2:
- Drop bindings patches
- Add patch to use dma memory space instead of the spi controllers when
dma is enabled.
- Drop iommu properties from final patch
- Link to v1: https://lore.kernel.org/r/20260515-tegra194-qspi-iommu-v1-0-57dfb63cd3d6@gmail.com
---
Aaron Kling (2):
spi: tegra210-quad: Allocate DMA memory for DMA engine
arm64: tegra: Enable DMA Support on Tegra194 QSPI
arch/arm64/boot/dts/nvidia/tegra194.dtsi | 4 ++++
drivers/spi/spi-tegra210-quad.c | 29 ++++++++++++++++++-----------
2 files changed, 22 insertions(+), 11 deletions(-)
---
base-commit: c1ecb239fa3456529a32255359fc78b69eb9d847
change-id: 20260515-tegra194-qspi-iommu-e4e4644d5fdf
Best regards,
--
Aaron Kling <webgeek1234@gmail.com>