From 982216a4290543fe73ae4f0a156f3d7906bd9b73 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Mon, 16 Apr 2012 13:04:46 -0300 Subject: [PATCH] edac.h: Add generic layers for describing a memory location The edac core were written with the idea that memory controllers are able to directly access csrows, and that the channels are used inside a csrows select. This is not true for FB-DIMM and RAMBUS memory controllers. Also, some recent advanced memory controllers don't present a per-csrows view. Instead, they view memories as DIMMs, instead of ranks, accessed via csrow/channel. So, changes are needed in order to allow the EDAC core to work with all types of architectures. In preparation for handling non-csrows based memory controllers, add some memory structs and a macro: enum hw_event_mc_err_type: describes the type of error (corrected, uncorrected, fatal) To be used by the new edac_mc_handle_error function; enum edac_mc_layer: describes the type of a given memory architecture layer (branch, channel, slot, csrow). struct edac_mc_layer: describes the properties of a memory layer (type, size, and if the layer will be used on a virtual csrow. EDAC_DIMM_PTR() - as the number of layers can vary from 1 to 3, this macro converts from an address with up to 3 layers into a linear address. Reviewed-by: Borislav Petkov Cc: Doug Thompson Signed-off-by: Mauro Carvalho Chehab --- include/linux/edac.h | 103 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 102 insertions(+), 1 deletion(-) diff --git a/include/linux/edac.h b/include/linux/edac.h index 67717cab1313..9e628434e164 100644 --- a/include/linux/edac.h +++ b/include/linux/edac.h @@ -70,6 +70,25 @@ enum dev_type { #define DEV_FLAG_X32 BIT(DEV_X32) #define DEV_FLAG_X64 BIT(DEV_X64) +/** + * enum hw_event_mc_err_type - type of the detected error + * + * @HW_EVENT_ERR_CORRECTED: Corrected Error - Indicates that an ECC + * corrected error was detected + * @HW_EVENT_ERR_UNCORRECTED: Uncorrected Error - Indicates an error that + * can't be corrected by ECC, but it is not + * fatal (maybe it is on an unused memory area, + * or the memory controller could recover from + * it for example, by re-trying the operation). + * @HW_EVENT_ERR_FATAL: Fatal Error - Uncorrected error that could not + * be recovered. + */ +enum hw_event_mc_err_type { + HW_EVENT_ERR_CORRECTED, + HW_EVENT_ERR_UNCORRECTED, + HW_EVENT_ERR_FATAL, +}; + /** * enum mem_type - memory types. For a more detailed reference, please see * http://en.wikipedia.org/wiki/DRAM @@ -312,7 +331,89 @@ enum scrub_type { * PS - I enjoyed writing all that about as much as you enjoyed reading it. */ -/* FIXME: add a per-dimm ce error count */ +/** + * enum edac_mc_layer - memory controller hierarchy layer + * + * @EDAC_MC_LAYER_BRANCH: memory layer is named "branch" + * @EDAC_MC_LAYER_CHANNEL: memory layer is named "channel" + * @EDAC_MC_LAYER_SLOT: memory layer is named "slot" + * @EDAC_MC_LAYER_CHIP_SELECT: memory layer is named "chip select" + * + * This enum is used by the drivers to tell edac_mc_sysfs what name should + * be used when describing a memory stick location. + */ +enum edac_mc_layer_type { + EDAC_MC_LAYER_BRANCH, + EDAC_MC_LAYER_CHANNEL, + EDAC_MC_LAYER_SLOT, + EDAC_MC_LAYER_CHIP_SELECT, +}; + +/** + * struct edac_mc_layer - describes the memory controller hierarchy + * @layer: layer type + * @size: number of components per layer. For example, + * if the channel layer has two channels, size = 2 + * @is_virt_csrow: This layer is part of the "csrow" when old API + * compatibility mode is enabled. Otherwise, it is + * a channel + */ +struct edac_mc_layer { + enum edac_mc_layer_type type; + unsigned size; + bool is_virt_csrow; +}; + +/* + * Maximum number of layers used by the memory controller to uniquely + * identify a single memory stick. + * NOTE: Changing this constant requires not only to change the constant + * below, but also to change the existing code at the core, as there are + * some code there that are optimized for 3 layers. + */ +#define EDAC_MAX_LAYERS 3 + +/** + * EDAC_DIMM_PTR - Macro responsible to find a pointer inside a pointer array + * for the element given by [layer0,layer1,layer2] position + * + * @layers: a struct edac_mc_layer array, describing how many elements + * were allocated for each layer + * @var: name of the var where we want to get the pointer + * (like mci->dimms) + * @n_layers: Number of layers at the @layers array + * @layer0: layer0 position + * @layer1: layer1 position. Unused if n_layers < 2 + * @layer2: layer2 position. Unused if n_layers < 3 + * + * For 1 layer, this macro returns &var[layer0] + * For 2 layers, this macro is similar to allocate a bi-dimensional array + * and to return "&var[layer0][layer1]" + * For 3 layers, this macro is similar to allocate a tri-dimensional array + * and to return "&var[layer0][layer1][layer2]" + * + * A loop could be used here to make it more generic, but, as we only have + * 3 layers, this is a little faster. + * By design, layers can never be 0 or more than 3. If that ever happens, + * a NULL is returned, causing an OOPS during the memory allocation routine, + * with would point to the developer that he's doing something wrong. + */ +#define EDAC_DIMM_PTR(layers, var, nlayers, layer0, layer1, layer2) ({ \ + typeof(var) __p; \ + if ((nlayers) == 1) \ + __p = &var[layer0]; \ + else if ((nlayers) == 2) \ + __p = &var[(layer1) + ((layers[1]).size * (layer0))]; \ + else if ((nlayers) == 3) \ + __p = &var[(layer2) + ((layers[2]).size * ((layer1) + \ + ((layers[1]).size * (layer0))))]; \ + else \ + __p = NULL; \ + __p; \ +}) + + +/* FIXME: add the proper per-location error counts */ struct dimm_info { char label[EDAC_MC_LABEL_LEN + 1]; /* DIMM label on motherboard */ unsigned memory_controller; -- 2.20.1