From 651f44674f4e26b4b16c9ff873bc9880f2014294 Mon Sep 17 00:00:00 2001 From: Channagoud Kadabi Date: Mon, 5 Nov 2018 16:22:29 -0800 Subject: [PATCH] drivers: of: Add API to find ddr device type Add API to find the ddr device type from memory node. Change-Id: I1cfc38d46f1ea0abc6fbe8cbb6e37cde72b9fc2e Signed-off-by: Channagoud Kadabi [eberman@codeaurora.org: Move func to header] Signed-off-by: Elliot Berman --- include/linux/of_fdt.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h index 9bbd5c06cb39..a46e8d845841 100644 --- a/include/linux/of_fdt.h +++ b/include/linux/of_fdt.h @@ -12,6 +12,7 @@ #include #include #include +#include /* Definitions used by the flattened device tree */ #define OF_DT_HEADER 0xd00dfeed /* marker */ @@ -38,6 +39,32 @@ extern char __dtb_end[]; /* Other Prototypes */ extern u64 of_flat_dt_translate_address(unsigned long node); extern void of_fdt_limit_memory(int limit); + +/** + * of_fdt_get_ddrtype - Return the type of ddr (4/5) on the current device + * + * On match, returns a non-zero positive value which matches the ddr type. + * Otherwise returns -ENOENT. + */ +static inline int of_fdt_get_ddrtype(void) +{ + int memory; + int len; + int ret; + fdt32_t *prop = NULL; + + memory = fdt_path_offset(initial_boot_params, "/memory"); + if (memory > 0) + prop = fdt_getprop_w(initial_boot_params, memory, + "ddr_device_type", &len); + + if (!prop || len != sizeof(u32)) + return -ENOENT; + + ret = fdt32_to_cpu(*prop); + + return ret; +} #endif /* CONFIG_OF_FLATTREE */ #ifdef CONFIG_OF_EARLY_FLATTREE