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baremetal: all examples working, all failures accounted for!

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SIMD&FP is now enabled in arm from bootloader.
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Ciro Santilli 六四事件 法轮功
2019-05-25 00:00:01 +00:00
parent 8825222579
commit add6eedb76
21 changed files with 181 additions and 90 deletions
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13
baremetal/lib/arm.S
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@@ -5,6 +5,19 @@ lkmc_start:
/* Prepare the stack for main, mandatory for C code. */
ldr sp, =stack_top
/* Enable floating point.
* Code copied from: http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0409h/CHDEGGFF.html
* Without this, SIMD operations such as vmov raise an exception.
*/
mrc p15, 0, r0, c1, c0, 2 /* Read CPACR into r0 */
orr r0, r0, 3 << 20 /* OR in User and Privileged access for CP10 */
orr r0, r0, 3 << 22 /* OR in User and Privileged access for CP11 */
bic r0, r0, 3 << 30 /* Clear ASEDIS/D32DIS if set */
mcr p15, 0, r0, c1, c0, 2 /* Store new access permissions into CPACR */
isb /* Ensure side-effect of CPACR is visible */
mov r0, 1 << 30 /* Create value with FPEXC (bit 30) set in r0 */
vmsr fpexc, r0 /* Enable VFP and SIMD extensions */
/* https://github.com/cirosantilli/linux-kernel-module-cheat#magic-failure-string */
ldr r0, =lkmc_baremetal_on_exit_callback
bl on_exit