aboutsummaryrefslogtreecommitdiff
path: root/hw/ppc4xx_devs.c
diff options
context:
space:
mode:
Diffstat (limited to 'hw/ppc4xx_devs.c')
-rw-r--r--hw/ppc4xx_devs.c42
1 files changed, 42 insertions, 0 deletions
diff --git a/hw/ppc4xx_devs.c b/hw/ppc4xx_devs.c
index 2d27e23ca9..939e0669e2 100644
--- a/hw/ppc4xx_devs.c
+++ b/hw/ppc4xx_devs.c
@@ -873,3 +873,45 @@ void ppc4xx_sdram_init (CPUState *env, qemu_irq irq, int nbanks,
sdram_map_bcr(sdram);
}
}
+
+/* Fill in consecutive SDRAM banks with 'ram_size' bytes of memory.
+ *
+ * sdram_bank_sizes[] must be 0-terminated.
+ *
+ * The 4xx SDRAM controller supports a small number of banks, and each bank
+ * must be one of a small set of sizes. The number of banks and the supported
+ * sizes varies by SoC. */
+ram_addr_t ppc4xx_sdram_adjust(ram_addr_t ram_size, int nr_banks,
+ target_phys_addr_t ram_bases[],
+ target_phys_addr_t ram_sizes[],
+ const unsigned int sdram_bank_sizes[])
+{
+ ram_addr_t ram_end = 0;
+ int i;
+ int j;
+
+ for (i = 0; i < nr_banks; i++) {
+ for (j = 0; sdram_bank_sizes[j] != 0; j++) {
+ unsigned int bank_size = sdram_bank_sizes[j];
+
+ if (bank_size <= ram_size) {
+ ram_bases[i] = ram_end;
+ ram_sizes[i] = bank_size;
+ ram_end += bank_size;
+ ram_size -= bank_size;
+ break;
+ }
+ }
+
+ if (!ram_size) {
+ /* No need to use the remaining banks. */
+ break;
+ }
+ }
+
+ if (ram_size)
+ printf("Truncating memory to %d MiB to fit SDRAM controller limits.\n",
+ (int)(ram_end >> 20));
+
+ return ram_end;
+}