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riscv_pmp.c: Revert LOG2_CEIL back to run-time log2ceil function

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The macro LOG2_CEIL is intended to be used in the pre-processor phase. If
used run-time it will generate a massive amount of extra code (~3.5K) which
is a problem, as the PMP configuration is quite often executed from a first
stage bootloader with a limited amount of code memory.

Code size differences pre- and post:

Memory region         Used Size  Region Size  %age Used
            envm:      112064 B     112384 B     99.72%

Memory region         Used Size  Region Size  %age Used
            envm:      108952 B     112384 B     96.95%
This commit is contained in:
Ville Juven 2023-12-12 15:54:37 +02:00 committed by Xiang Xiao
parent 614570cdcb
commit 7bcbaa5dc7
1 changed files with 27 additions and 2 deletions
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29
arch/risc-v/src/common/riscv_pmp.c
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@ -32,7 +32,6 @@
#include <nuttx/compiler.h>
#include <nuttx/arch.h>
#include <nuttx/irq.h>
#include <nuttx/lib/math32.h>
#include "riscv_internal.h"
@ -89,6 +88,32 @@ typedef struct pmp_entry_s pmp_entry_t;
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: log2ceil
*
* Description:
* Calculate the up-rounded power-of-two for input.
*
* Input Parameters:
* x - Argument to calculate the power-of-two from.
*
* Returned Value:
* Power-of-two for argument, rounded up.
*
****************************************************************************/
static uintptr_t log2ceil(uintptr_t x)
{
uintptr_t pot = 0;
for (x = x - 1; x; x >>= 1)
{
pot++;
}
return pot;
}
/****************************************************************************
* Name: pmp_check_region_attrs
*
@ -143,7 +168,7 @@ static bool pmp_check_region_attrs(uintptr_t base, uintptr_t size,
/* Get the power-of-two for size, rounded up */
if ((base & ((UINT64_C(1) << LOG2_CEIL(size)) - 1)) != 0)
if ((base & ((UINT64_C(1) << log2ceil(size)) - 1)) != 0)
{
/* The start address is not properly aligned with size */