diff options
Diffstat (limited to 'arch/powerpc/mm/drmem.c')
| -rw-r--r-- | arch/powerpc/mm/drmem.c | 516 |
1 files changed, 516 insertions, 0 deletions
diff --git a/arch/powerpc/mm/drmem.c b/arch/powerpc/mm/drmem.c new file mode 100644 index 000000000..2369d1bf2 --- /dev/null +++ b/arch/powerpc/mm/drmem.c @@ -0,0 +1,516 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Dynamic reconfiguration memory support + * + * Copyright 2017 IBM Corporation + */ + +#define pr_fmt(fmt) "drmem: " fmt + +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/memblock.h> +#include <linux/slab.h> +#include <asm/drmem.h> + +static int n_root_addr_cells, n_root_size_cells; + +static struct drmem_lmb_info __drmem_info; +struct drmem_lmb_info *drmem_info = &__drmem_info; +static bool in_drmem_update; + +u64 drmem_lmb_memory_max(void) +{ + struct drmem_lmb *last_lmb; + + last_lmb = &drmem_info->lmbs[drmem_info->n_lmbs - 1]; + return last_lmb->base_addr + drmem_lmb_size(); +} + +static u32 drmem_lmb_flags(struct drmem_lmb *lmb) +{ + /* + * Return the value of the lmb flags field minus the reserved + * bit used internally for hotplug processing. + */ + return lmb->flags & ~DRMEM_LMB_RESERVED; +} + +static struct property *clone_property(struct property *prop, u32 prop_sz) +{ + struct property *new_prop; + + new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL); + if (!new_prop) + return NULL; + + new_prop->name = kstrdup(prop->name, GFP_KERNEL); + new_prop->value = kzalloc(prop_sz, GFP_KERNEL); + if (!new_prop->name || !new_prop->value) { + kfree(new_prop->name); + kfree(new_prop->value); + kfree(new_prop); + return NULL; + } + + new_prop->length = prop_sz; +#if defined(CONFIG_OF_DYNAMIC) + of_property_set_flag(new_prop, OF_DYNAMIC); +#endif + return new_prop; +} + +static int drmem_update_dt_v1(struct device_node *memory, + struct property *prop) +{ + struct property *new_prop; + struct of_drconf_cell_v1 *dr_cell; + struct drmem_lmb *lmb; + u32 *p; + + new_prop = clone_property(prop, prop->length); + if (!new_prop) + return -1; + + p = new_prop->value; + *p++ = cpu_to_be32(drmem_info->n_lmbs); + + dr_cell = (struct of_drconf_cell_v1 *)p; + + for_each_drmem_lmb(lmb) { + dr_cell->base_addr = cpu_to_be64(lmb->base_addr); + dr_cell->drc_index = cpu_to_be32(lmb->drc_index); + dr_cell->aa_index = cpu_to_be32(lmb->aa_index); + dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb)); + + dr_cell++; + } + + of_update_property(memory, new_prop); + return 0; +} + +static void init_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell, + struct drmem_lmb *lmb) +{ + dr_cell->base_addr = cpu_to_be64(lmb->base_addr); + dr_cell->drc_index = cpu_to_be32(lmb->drc_index); + dr_cell->aa_index = cpu_to_be32(lmb->aa_index); + dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb)); +} + +static int drmem_update_dt_v2(struct device_node *memory, + struct property *prop) +{ + struct property *new_prop; + struct of_drconf_cell_v2 *dr_cell; + struct drmem_lmb *lmb, *prev_lmb; + u32 lmb_sets, prop_sz, seq_lmbs; + u32 *p; + + /* First pass, determine how many LMB sets are needed. */ + lmb_sets = 0; + prev_lmb = NULL; + for_each_drmem_lmb(lmb) { + if (!prev_lmb) { + prev_lmb = lmb; + lmb_sets++; + continue; + } + + if (prev_lmb->aa_index != lmb->aa_index || + drmem_lmb_flags(prev_lmb) != drmem_lmb_flags(lmb)) + lmb_sets++; + + prev_lmb = lmb; + } + + prop_sz = lmb_sets * sizeof(*dr_cell) + sizeof(__be32); + new_prop = clone_property(prop, prop_sz); + if (!new_prop) + return -1; + + p = new_prop->value; + *p++ = cpu_to_be32(lmb_sets); + + dr_cell = (struct of_drconf_cell_v2 *)p; + + /* Second pass, populate the LMB set data */ + prev_lmb = NULL; + seq_lmbs = 0; + for_each_drmem_lmb(lmb) { + if (prev_lmb == NULL) { + /* Start of first LMB set */ + prev_lmb = lmb; + init_drconf_v2_cell(dr_cell, lmb); + seq_lmbs++; + continue; + } + + if (prev_lmb->aa_index != lmb->aa_index || + drmem_lmb_flags(prev_lmb) != drmem_lmb_flags(lmb)) { + /* end of one set, start of another */ + dr_cell->seq_lmbs = cpu_to_be32(seq_lmbs); + dr_cell++; + + init_drconf_v2_cell(dr_cell, lmb); + seq_lmbs = 1; + } else { + seq_lmbs++; + } + + prev_lmb = lmb; + } + + /* close out last LMB set */ + dr_cell->seq_lmbs = cpu_to_be32(seq_lmbs); + of_update_property(memory, new_prop); + return 0; +} + +int drmem_update_dt(void) +{ + struct device_node *memory; + struct property *prop; + int rc = -1; + + memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); + if (!memory) + return -1; + + /* + * Set in_drmem_update to prevent the notifier callback to process the + * DT property back since the change is coming from the LMB tree. + */ + in_drmem_update = true; + prop = of_find_property(memory, "ibm,dynamic-memory", NULL); + if (prop) { + rc = drmem_update_dt_v1(memory, prop); + } else { + prop = of_find_property(memory, "ibm,dynamic-memory-v2", NULL); + if (prop) + rc = drmem_update_dt_v2(memory, prop); + } + in_drmem_update = false; + + of_node_put(memory); + return rc; +} + +static void read_drconf_v1_cell(struct drmem_lmb *lmb, + const __be32 **prop) +{ + const __be32 *p = *prop; + + lmb->base_addr = of_read_number(p, n_root_addr_cells); + p += n_root_addr_cells; + lmb->drc_index = of_read_number(p++, 1); + + p++; /* skip reserved field */ + + lmb->aa_index = of_read_number(p++, 1); + lmb->flags = of_read_number(p++, 1); + + *prop = p; +} + +static int +__walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm, void *data, + int (*func)(struct drmem_lmb *, const __be32 **, void *)) +{ + struct drmem_lmb lmb; + u32 i, n_lmbs; + int ret = 0; + + n_lmbs = of_read_number(prop++, 1); + for (i = 0; i < n_lmbs; i++) { + read_drconf_v1_cell(&lmb, &prop); + ret = func(&lmb, &usm, data); + if (ret) + break; + } + + return ret; +} + +static void read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell, + const __be32 **prop) +{ + const __be32 *p = *prop; + + dr_cell->seq_lmbs = of_read_number(p++, 1); + dr_cell->base_addr = of_read_number(p, n_root_addr_cells); + p += n_root_addr_cells; + dr_cell->drc_index = of_read_number(p++, 1); + dr_cell->aa_index = of_read_number(p++, 1); + dr_cell->flags = of_read_number(p++, 1); + + *prop = p; +} + +static int +__walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm, void *data, + int (*func)(struct drmem_lmb *, const __be32 **, void *)) +{ + struct of_drconf_cell_v2 dr_cell; + struct drmem_lmb lmb; + u32 i, j, lmb_sets; + int ret = 0; + + lmb_sets = of_read_number(prop++, 1); + for (i = 0; i < lmb_sets; i++) { + read_drconf_v2_cell(&dr_cell, &prop); + + for (j = 0; j < dr_cell.seq_lmbs; j++) { + lmb.base_addr = dr_cell.base_addr; + dr_cell.base_addr += drmem_lmb_size(); + + lmb.drc_index = dr_cell.drc_index; + dr_cell.drc_index++; + + lmb.aa_index = dr_cell.aa_index; + lmb.flags = dr_cell.flags; + + ret = func(&lmb, &usm, data); + if (ret) + break; + } + } + + return ret; +} + +#ifdef CONFIG_PPC_PSERIES +int __init walk_drmem_lmbs_early(unsigned long node, void *data, + int (*func)(struct drmem_lmb *, const __be32 **, void *)) +{ + const __be32 *prop, *usm; + int len, ret = -ENODEV; + + prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len); + if (!prop || len < dt_root_size_cells * sizeof(__be32)) + return ret; + + /* Get the address & size cells */ + n_root_addr_cells = dt_root_addr_cells; + n_root_size_cells = dt_root_size_cells; + + drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop); + + usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory", &len); + + prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &len); + if (prop) { + ret = __walk_drmem_v1_lmbs(prop, usm, data, func); + } else { + prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory-v2", + &len); + if (prop) + ret = __walk_drmem_v2_lmbs(prop, usm, data, func); + } + + memblock_dump_all(); + return ret; +} + +/* + * Update the LMB associativity index. + */ +static int update_lmb(struct drmem_lmb *updated_lmb, + __maybe_unused const __be32 **usm, + __maybe_unused void *data) +{ + struct drmem_lmb *lmb; + + for_each_drmem_lmb(lmb) { + if (lmb->drc_index != updated_lmb->drc_index) + continue; + + lmb->aa_index = updated_lmb->aa_index; + break; + } + return 0; +} + +/* + * Update the LMB associativity index. + * + * This needs to be called when the hypervisor is updating the + * dynamic-reconfiguration-memory node property. + */ +void drmem_update_lmbs(struct property *prop) +{ + /* + * Don't update the LMBs if triggered by the update done in + * drmem_update_dt(), the LMB values have been used to the update the DT + * property in that case. + */ + if (in_drmem_update) + return; + if (!strcmp(prop->name, "ibm,dynamic-memory")) + __walk_drmem_v1_lmbs(prop->value, NULL, NULL, update_lmb); + else if (!strcmp(prop->name, "ibm,dynamic-memory-v2")) + __walk_drmem_v2_lmbs(prop->value, NULL, NULL, update_lmb); +} +#endif + +static int init_drmem_lmb_size(struct device_node *dn) +{ + const __be32 *prop; + int len; + + if (drmem_info->lmb_size) + return 0; + + prop = of_get_property(dn, "ibm,lmb-size", &len); + if (!prop || len < n_root_size_cells * sizeof(__be32)) { + pr_info("Could not determine LMB size\n"); + return -1; + } + + drmem_info->lmb_size = of_read_number(prop, n_root_size_cells); + return 0; +} + +/* + * Returns the property linux,drconf-usable-memory if + * it exists (the property exists only in kexec/kdump kernels, + * added by kexec-tools) + */ +static const __be32 *of_get_usable_memory(struct device_node *dn) +{ + const __be32 *prop; + u32 len; + + prop = of_get_property(dn, "linux,drconf-usable-memory", &len); + if (!prop || len < sizeof(unsigned int)) + return NULL; + + return prop; +} + +int walk_drmem_lmbs(struct device_node *dn, void *data, + int (*func)(struct drmem_lmb *, const __be32 **, void *)) +{ + const __be32 *prop, *usm; + int ret = -ENODEV; + + if (!of_root) + return ret; + + /* Get the address & size cells */ + of_node_get(of_root); + n_root_addr_cells = of_n_addr_cells(of_root); + n_root_size_cells = of_n_size_cells(of_root); + of_node_put(of_root); + + if (init_drmem_lmb_size(dn)) + return ret; + + usm = of_get_usable_memory(dn); + + prop = of_get_property(dn, "ibm,dynamic-memory", NULL); + if (prop) { + ret = __walk_drmem_v1_lmbs(prop, usm, data, func); + } else { + prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL); + if (prop) + ret = __walk_drmem_v2_lmbs(prop, usm, data, func); + } + + return ret; +} + +static void __init init_drmem_v1_lmbs(const __be32 *prop) +{ + struct drmem_lmb *lmb; + + drmem_info->n_lmbs = of_read_number(prop++, 1); + if (drmem_info->n_lmbs == 0) + return; + + drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb), + GFP_KERNEL); + if (!drmem_info->lmbs) + return; + + for_each_drmem_lmb(lmb) + read_drconf_v1_cell(lmb, &prop); +} + +static void __init init_drmem_v2_lmbs(const __be32 *prop) +{ + struct drmem_lmb *lmb; + struct of_drconf_cell_v2 dr_cell; + const __be32 *p; + u32 i, j, lmb_sets; + int lmb_index; + + lmb_sets = of_read_number(prop++, 1); + if (lmb_sets == 0) + return; + + /* first pass, calculate the number of LMBs */ + p = prop; + for (i = 0; i < lmb_sets; i++) { + read_drconf_v2_cell(&dr_cell, &p); + drmem_info->n_lmbs += dr_cell.seq_lmbs; + } + + drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb), + GFP_KERNEL); + if (!drmem_info->lmbs) + return; + + /* second pass, read in the LMB information */ + lmb_index = 0; + p = prop; + + for (i = 0; i < lmb_sets; i++) { + read_drconf_v2_cell(&dr_cell, &p); + + for (j = 0; j < dr_cell.seq_lmbs; j++) { + lmb = &drmem_info->lmbs[lmb_index++]; + + lmb->base_addr = dr_cell.base_addr; + dr_cell.base_addr += drmem_info->lmb_size; + + lmb->drc_index = dr_cell.drc_index; + dr_cell.drc_index++; + + lmb->aa_index = dr_cell.aa_index; + lmb->flags = dr_cell.flags; + } + } +} + +static int __init drmem_init(void) +{ + struct device_node *dn; + const __be32 *prop; + + dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); + if (!dn) { + pr_info("No dynamic reconfiguration memory found\n"); + return 0; + } + + if (init_drmem_lmb_size(dn)) { + of_node_put(dn); + return 0; + } + + prop = of_get_property(dn, "ibm,dynamic-memory", NULL); + if (prop) { + init_drmem_v1_lmbs(prop); + } else { + prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL); + if (prop) + init_drmem_v2_lmbs(prop); + } + + of_node_put(dn); + return 0; +} +late_initcall(drmem_init); |