From: Carlos Munoz <cmunoz@xxxxxxxxxx> Add a global resource manager to manage tagged pointers within bootmem allocated memory. This is used by various functional blocks in the Octeon core like the FPA, Ethernet nexus, etc. Signed-off-by: Carlos Munoz <cmunoz@xxxxxxxxxx> Signed-off-by: Steven J. Hill <Steven.Hill@xxxxxxxxxx> Signed-off-by: David Daney <david.daney@xxxxxxxxxx> --- arch/mips/cavium-octeon/Makefile | 1 + arch/mips/cavium-octeon/resource-mgr.c | 351 +++++++++++++++++++++++++++++++++ arch/mips/include/asm/octeon/octeon.h | 18 ++ 3 files changed, 370 insertions(+) create mode 100644 arch/mips/cavium-octeon/resource-mgr.c diff --git a/arch/mips/cavium-octeon/Makefile b/arch/mips/cavium-octeon/Makefile index 7c02e542959a..28c0bb75d1a4 100644 --- a/arch/mips/cavium-octeon/Makefile +++ b/arch/mips/cavium-octeon/Makefile @@ -10,6 +10,7 @@ # obj-y := cpu.o setup.o octeon-platform.o octeon-irq.o csrc-octeon.o +obj-y += resource-mgr.o obj-y += dma-octeon.o obj-y += octeon-memcpy.o obj-y += executive/ diff --git a/arch/mips/cavium-octeon/resource-mgr.c b/arch/mips/cavium-octeon/resource-mgr.c new file mode 100644 index 000000000000..74efda5420ff --- /dev/null +++ b/arch/mips/cavium-octeon/resource-mgr.c @@ -0,0 +1,351 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Resource manager for Octeon. + * + * Copyright (C) 2017 Cavium, Inc. + */ +#include <linux/module.h> + +#include <asm/octeon/octeon.h> +#include <asm/octeon/cvmx-bootmem.h> + +#define RESOURCE_MGR_BLOCK_NAME "cvmx-global-resources" +#define MAX_RESOURCES 128 +#define INST_AVAILABLE -88 +#define OWNER 0xbadc0de + +struct global_resource_entry { + struct global_resource_tag tag; + u64 phys_addr; + u64 size; +}; + +struct global_resources { +#ifdef __LITTLE_ENDIAN_BITFIELD + u32 rlock; + u32 pad; +#else + u32 pad; + u32 rlock; +#endif + u64 entry_cnt; + struct global_resource_entry resource_entry[]; +}; + +static struct global_resources *res_mgr_info; + + +/* + * The resource manager interacts with software running outside of the + * Linux kernel, which necessitates locking to maintain data structure + * consistency. These custom locking functions implement the locking + * protocol, and cannot be replaced by kernel locking functions that + * may use different in-memory structures. + */ + +static void res_mgr_lock(void) +{ + while (cmpxchg(&res_mgr_info->rlock, 0, 1)) + ; /* Loop while not zero */ + rmb(); +} + +static void res_mgr_unlock(void) +{ + /* Wait until all resource operations finish before unlocking. */ + wmb(); + WRITE_ONCE(res_mgr_info->rlock, 0); + /* Force a write buffer flush. */ + wmb(); +} + +static int res_mgr_find_resource(struct global_resource_tag tag) +{ + struct global_resource_entry *res_entry; + int i; + + for (i = 0; i < res_mgr_info->entry_cnt; i++) { + res_entry = &res_mgr_info->resource_entry[i]; + if (res_entry->tag.lo == tag.lo && res_entry->tag.hi == tag.hi) + return i; + } + return -1; +} + +/** + * res_mgr_create_resource() - Create a resource. + * @tag: Identifies the resource. + * @inst_cnt: Number of resource instances to create. + * + * Returns 0 if the source was created successfully. + * Returns < 0 for error codes. + */ +int res_mgr_create_resource(struct global_resource_tag tag, int inst_cnt) +{ + struct global_resource_entry *res_entry; + u64 size; + u64 *res_addr; + int res_index, i, rc = 0; + + res_mgr_lock(); + + /* Make sure resource doesn't already exist. */ + res_index = res_mgr_find_resource(tag); + if (res_index >= 0) { + rc = -EEXIST; + goto err; + } + + if (res_mgr_info->entry_cnt >= MAX_RESOURCES) { + pr_err("Resource max limit reached, not created\n"); + rc = -ENOSPC; + goto err; + } + + /* + * Each instance is kept in an array of u64s. The first array element + * holds the number of allocated instances. + */ + size = sizeof(u64) * (inst_cnt + 1); + res_addr = cvmx_bootmem_alloc_range(size, CVMX_CACHE_LINE_SIZE, 0, 0); + if (!res_addr) { + pr_err("Failed to allocate resource. not created\n"); + rc = -ENOMEM; + goto err; + } + + /* Initialize the newly created resource. */ + *res_addr = inst_cnt; + for (i = 1; i <= inst_cnt; i++) + res_addr[i] = INST_AVAILABLE; + + res_index = res_mgr_info->entry_cnt; + res_entry = &res_mgr_info->resource_entry[res_index]; + res_entry->tag = tag; + res_entry->phys_addr = virt_to_phys(res_addr); + res_entry->size = size; + res_mgr_info->entry_cnt++; + +err: + res_mgr_unlock(); + + return rc; +} +EXPORT_SYMBOL(res_mgr_create_resource); + +/** + * res_mgr_alloc_range() - Allocate a range of resource instances. + * @tag: Identifies the resource. + * @req_inst: Requested start of instance range to allocate. + * Range instances are guaranteed to be sequential + * (-1 for don't care). + * @req_cnt: Number of instances to allocate. + * @use_last_avail: Set to request the last available instance. + * @inst: Updated with the allocated instances. + * + * Returns 0 if the source was created successfully. + * Returns < 0 for error codes. + */ +int res_mgr_alloc_range(struct global_resource_tag tag, int req_inst, + int req_cnt, bool use_last_avail, int *inst) +{ + struct global_resource_entry *res_entry; + int res_index; + u64 *res_addr; + u64 inst_cnt; + int alloc_cnt, i, rc = -ENOENT; + + /* Start with no instances allocated. */ + for (i = 0; i < req_cnt; i++) + inst[i] = INST_AVAILABLE; + + res_mgr_lock(); + + /* Find the resource. */ + res_index = res_mgr_find_resource(tag); + if (res_index < 0) { + pr_err("Resource not found, can't allocate instance\n"); + goto err; + } + + /* Get resource data. */ + res_entry = &res_mgr_info->resource_entry[res_index]; + res_addr = phys_to_virt(res_entry->phys_addr); + inst_cnt = *res_addr; + + /* Allocate the requested instances. */ + if (req_inst >= 0) { + /* Specific instance range requested. */ + if (req_inst + req_cnt >= inst_cnt) { + pr_err("Requested instance out of range\n"); + goto err; + } + + for (i = 0; i < req_cnt; i++) { + if (*(res_addr + req_inst + 1 + i) == INST_AVAILABLE) { + inst[i] = req_inst + i; + } else { + inst[0] = INST_AVAILABLE; + break; + } + } + } else if (use_last_avail) { + /* Last available instance requested. */ + alloc_cnt = 0; + for (i = inst_cnt; i > 0; i--) { + if (*(res_addr + i) == INST_AVAILABLE) { + /* + * Instance off by 1 (first element holds the + * count). + */ + inst[alloc_cnt] = i - 1; + + alloc_cnt++; + if (alloc_cnt == req_cnt) + break; + } + } + + if (i == 0) + inst[0] = INST_AVAILABLE; + } else { + /* Next available instance requested. */ + alloc_cnt = 0; + for (i = 1; i <= inst_cnt; i++) { + if (*(res_addr + i) == INST_AVAILABLE) { + /* + * Instance off by 1 (first element holds the + * count). + */ + inst[alloc_cnt] = i - 1; + + alloc_cnt++; + if (alloc_cnt == req_cnt) + break; + } + } + + if (i > inst_cnt) + inst[0] = INST_AVAILABLE; + } + + if (inst[0] != INST_AVAILABLE) { + for (i = 0; i < req_cnt; i++) + *(res_addr + inst[i] + 1) = OWNER; + rc = 0; + } + +err: + res_mgr_unlock(); + + return rc; +} +EXPORT_SYMBOL(res_mgr_alloc_range); + +/** + * res_mgr_alloc() - Allocate a resource instance. + * @tag: Identifies the resource. + * @req_inst: Requested instance to allocate (-1 for don't care). + * @use_last_avail: Set to request the last available instance. + * + * Returns: Allocated resource instance if successful. + * Returns <0 for error codes. + */ +int res_mgr_alloc(struct global_resource_tag tag, int req_inst, + bool use_last_avail) +{ + int inst, rc; + + rc = res_mgr_alloc_range(tag, req_inst, 1, use_last_avail, &inst); + if (!rc) + return inst; + return rc; +} +EXPORT_SYMBOL(res_mgr_alloc); + +/** + * res_mgr_free_range() - Free a resource instance range. + * @tag: Identifies the resource. + * @inst: Requested instance to free. + * @req_cnt: Number of instances to free. + */ +void res_mgr_free_range(struct global_resource_tag tag, const int *inst, + int req_cnt) +{ + struct global_resource_entry *res_entry; + int res_index, i; + u64 *res_addr; + + res_mgr_lock(); + + /* Find the resource. */ + res_index = res_mgr_find_resource(tag); + if (res_index < 0) { + pr_err("Resource not found, can't free instance\n"); + goto err; + } + + /* Get the resource data. */ + res_entry = &res_mgr_info->resource_entry[res_index]; + res_addr = phys_to_virt(res_entry->phys_addr); + + /* Free the resource instances. */ + for (i = 0; i < req_cnt; i++) { + /* Instance off by 1 (first element holds the count). */ + *(res_addr + inst[i] + 1) = INST_AVAILABLE; + } + +err: + res_mgr_unlock(); +} +EXPORT_SYMBOL(res_mgr_free_range); + +/** + * res_mgr_free() - Free a resource instance. + * @tag: Identifies the resource. + * @req_inst: Requested instance to free. + */ +void res_mgr_free(struct global_resource_tag tag, int inst) +{ + res_mgr_free_range(tag, &inst, 1); +} +EXPORT_SYMBOL(res_mgr_free); + +static int __init res_mgr_init(void) +{ + struct cvmx_bootmem_named_block_desc *block; + int block_size; + u64 addr; + + cvmx_bootmem_lock(); + + /* Search for the resource manager data in boot memory. */ + block = cvmx_bootmem_phy_named_block_find(RESOURCE_MGR_BLOCK_NAME, + CVMX_BOOTMEM_FLAG_NO_LOCKING); + if (block) { + /* Found. */ + res_mgr_info = phys_to_virt(block->base_addr); + } else { + /* Create it. */ + block_size = sizeof(struct global_resources) + + sizeof(struct global_resource_entry) * MAX_RESOURCES; + addr = cvmx_bootmem_phy_named_block_alloc(block_size, 0, 0, + CVMX_CACHE_LINE_SIZE, RESOURCE_MGR_BLOCK_NAME, + CVMX_BOOTMEM_FLAG_NO_LOCKING); + if (!addr) { + pr_err("Failed to allocate name block %s\n", + RESOURCE_MGR_BLOCK_NAME); + } else { + res_mgr_info = phys_to_virt(addr); + memset(res_mgr_info, 0, block_size); + } + } + + cvmx_bootmem_unlock(); + + return 0; +} +device_initcall(res_mgr_init); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Cavium, Inc. Octeon resource manager"); diff --git a/arch/mips/include/asm/octeon/octeon.h b/arch/mips/include/asm/octeon/octeon.h index f01af2469874..4dafeaf262b5 100644 --- a/arch/mips/include/asm/octeon/octeon.h +++ b/arch/mips/include/asm/octeon/octeon.h @@ -346,6 +346,24 @@ void octeon_mult_restore3_end(void); void octeon_mult_restore2(void); void octeon_mult_restore2_end(void); +/* + * This definition must be kept in sync with the one in + * cvmx-global-resources.c + */ +struct global_resource_tag { + uint64_t lo; + uint64_t hi; +}; + +void res_mgr_free(struct global_resource_tag tag, int inst); +void res_mgr_free_range(struct global_resource_tag tag, const int *inst, + int req_cnt); +int res_mgr_alloc(struct global_resource_tag tag, int req_inst, + bool use_last_avail); +int res_mgr_alloc_range(struct global_resource_tag tag, int req_inst, + int req_cnt, bool use_last_avail, int *inst); +int res_mgr_create_resource(struct global_resource_tag tag, int inst_cnt); + /** * Read a 32bit value from the Octeon NPI register space * -- 2.14.3