ddr: fsl: Fix fsl_ddr_sdram_size() for 4GB modules with 32-bit phys_size_t
Function fsl_ddr_compute() always return size in unsigned long long type,
but function fsl_ddr_sdram_size() returns size in phys_size_t type.
When 36-bit addressing mode is not enabled then phys_size_t type is only
32-bit and thus it cannot store value 4GB (0x100000000). Function
fsl_ddr_sdram_size() in this case returns truncated value 0x0.
Fix this issue by returning the highest representable value, which is
0xffffffff (4GB - 1 byte).
This change fixes crashing of proper U-Boot because it detected 4 GB module
as RAM with zero size.
Signed-off-by: Pali Rohár <pali@kernel.org>
diff --git a/drivers/ddr/fsl/main.c b/drivers/ddr/fsl/main.c
index 020adb0..d44f16c 100644
--- a/drivers/ddr/fsl/main.c
+++ b/drivers/ddr/fsl/main.c
@@ -950,5 +950,9 @@
/* Compute it once normally. */
total_memory = fsl_ddr_compute(&info, STEP_GET_SPD, 1);
+ /* Ensure that total_memory does not overflow on return */
+ if (total_memory > (phys_size_t)~0ULL)
+ total_memory = (phys_size_t)~0ULL;
+
return total_memory;
}