U-Boot core code already handles the case when RAM size is bigger than CONFIG_MAX_MEM_MAPPED. So there is no need to do duplicate check in fsl ddr driver for CONFIG_MAX_MEM_MAPPED. Instead simplify code to just check if RAM size can be representable in phys_size_t type. And avoid printing warning if phys_size_t is just 1 byte smaller than RAM size, which is the typical situation with 4 GB DDR module.
Signed-off-by: Pali Rohár pali@kernel.org --- drivers/ddr/fsl/main.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/ddr/fsl/main.c b/drivers/ddr/fsl/main.c index dd55e61a7a73..577ca569b042 100644 --- a/drivers/ddr/fsl/main.c +++ b/drivers/ddr/fsl/main.c @@ -856,15 +856,18 @@ phys_size_t __fsl_ddr_sdram(fsl_ddr_info_t *pinfo) debug("total_memory by %s = %llu\n", __func__, total_memory);
#if !defined(CONFIG_PHYS_64BIT) - /* Check for more than max memory. Bad. */ - if ((first_ctrl == 0) && (total_memory > CONFIG_MAX_MEM_MAPPED)) { + /* + * Show warning about big DDR moodules. But avoid warning for 4 GB DDR + * modules when U-Boot supports RAM of maximal size 4 GB - 1 byte. + */ + if ((first_ctrl == 0) && (total_memory - 1 > (phys_size_t)~0ULL)) { puts("Detected "); print_size(total_memory, " of memory\n"); #ifndef CONFIG_SPL_BUILD puts(" "); /* re-align to match init_dram print */ #endif puts("This U-Boot only supports <= "); - print_size(CONFIG_MAX_MEM_MAPPED, " of DDR\n"); + print_size((unsigned long long)((phys_size_t)~0ULL)+1, " of DDR\n"); #ifndef CONFIG_SPL_BUILD puts(" "); /* re-align to match init_dram print */ #endif @@ -872,10 +875,13 @@ phys_size_t __fsl_ddr_sdram(fsl_ddr_info_t *pinfo) #ifndef CONFIG_SPL_BUILD puts(" "); /* re-align to match init_dram print */ #endif - total_memory = CONFIG_MAX_MEM_MAPPED; } #endif
+ /* 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; }