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After enabling TrustZone various parts of the CAAM silicon become inaccessible to non TrustZone contexts. The job-ring registers are designed to allow non TrustZone contexts like Linux to still submit jobs to CAAM even after TrustZone has been enabled. The default job-ring permissions after the BootROM look like this for job-ring zero. ms=0x00008001 ls=0x00008001 The MS field is JRaMIDR_MS (job ring MID most significant). Referring to "Security Reference Manual for i.MX 7Dual and 7Solo Applications Processors, Rev. 0, 03/2017" section 8.10.4 we see that JROWN_NS controls whether or not a job-ring is accessible from non TrustZone. Bit 15 (TrustZone) is the logical inverse of bit 3 hence the above value of 0x8001 shows that JROWN_NS=0 and TrustZone=1. Clearly then as soon as TrustZone becomes active the job-ring registers are no longer accessible from Linux, which is not what we want. This patch explicitly sets all job-ring registers to JROWN_NS=1 (non TrustZone) by default and to the Non-Secure MID 001. Both settings are required to successfully assign a job-ring to non-secure mode. If a piece of TrustZone firmware requires ownership of job-ring registers it can unset the JROWN_NS bit itself. This patch in conjunction with a modification of the Linux kernel to skip HWRNG initialisation makes CAAM usable to Linux with TrustZone enabled. Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> Cc: Fabio Estevam <fabio.estevam@nxp.com> Cc: Peng Fan <peng.fan@nxp.com> Cc: Alex Porosanu <alexandru.porosanu@nxp.com> Cc: Ruchika Gupta <ruchika.gupta@nxp.com> Cc: Aneesh Bansal <aneesh.bansal@nxp.com> Link: https://github.com/OP-TEE/optee_os/issues/1408 Link: https://tinyurl.com/yam5gv9a Tested-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de> |
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| bios_emulator | ||
| block | ||
| bootcount | ||
| clk | ||
| core | ||
| cpu | ||
| crypto | ||
| ddr | ||
| demo | ||
| dfu | ||
| dma | ||
| firmware | ||
| fpga | ||
| gpio | ||
| i2c | ||
| input | ||
| led | ||
| mailbox | ||
| memory | ||
| misc | ||
| mmc | ||
| mtd | ||
| net | ||
| nvme | ||
| pch | ||
| pci | ||
| pcmcia | ||
| phy | ||
| pinctrl | ||
| power | ||
| pwm | ||
| qe | ||
| ram | ||
| remoteproc | ||
| reset | ||
| rtc | ||
| scsi | ||
| serial | ||
| soc | ||
| sound | ||
| spi | ||
| spmi | ||
| sysreset | ||
| thermal | ||
| timer | ||
| tpm | ||
| usb | ||
| video | ||
| watchdog | ||
| Kconfig | ||
| Makefile | ||