On Mon, 29 Jun 2020, Philippe Mathieu-Daudé wrote:
Use popcount instruction to count the number of bits set in
the RAM size. Allow at most 1 bit for each bank. This avoid
using invalid hardware configurations.
Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org>
---
hw/ppc/ppc4xx_devs.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/hw/ppc/ppc4xx_devs.c b/hw/ppc/ppc4xx_devs.c
index f1651e04d9..c2484a5695 100644
--- a/hw/ppc/ppc4xx_devs.c
+++ b/hw/ppc/ppc4xx_devs.c
@@ -687,6 +687,15 @@ void ppc4xx_sdram_banks(MemoryRegion *ram, int nr_banks,
int i;
int j;
+ if (ctpop64(size_left) > nr_banks) {
+ if (nr_banks) {
+ error_report("RAM size must be a power of 2");
+ } else {
+ error_report("RAM size must be the combination of %d powers of 2",
+ nr_banks);
+ }
+ exit(1);
What is this supposed to fix? Is it a good idea to exit() from a helper? I
don't think so because the board code should be in control in my opinion
to decide what it can work with or what it cannot handle and wants to
abort. So maybe it's better to return error in some way and let board code
handle it. (We already exit from this function but that was added in
commit a0258e4afa1 when the size fix up was removed due to memdev. That
exit uses EXIT_FAILURE constant.)
Regards,
BALATON Zoltan
+ }
for (i = 0; i < nr_banks; i++) {
for (j = 0; sdram_bank_sizes[j] != 0; j++) {
bank_size = sdram_bank_sizes[j];
