On 2/17/21 10:40 PM, Lizhi Hou wrote: > XRT drivers use device tree as metadata format to discover HW subsystems > behind PCIe BAR. Thus libfdt functions are called for driver to parse for the driver to parse the > device tree blob. > > Signed-off-by: Sonal Santan <sonal.santan@xxxxxxxxxx> > Signed-off-by: Max Zhen <max.zhen@xxxxxxxxxx> > Signed-off-by: Lizhi Hou <lizhih@xxxxxxxxxx> > --- > drivers/fpga/xrt/include/metadata.h | 229 ++++++++++++ > drivers/fpga/xrt/metadata/metadata.c | 524 +++++++++++++++++++++++++++ > 2 files changed, 753 insertions(+) > create mode 100644 drivers/fpga/xrt/include/metadata.h > create mode 100644 drivers/fpga/xrt/metadata/metadata.c > > diff --git a/drivers/fpga/xrt/include/metadata.h b/drivers/fpga/xrt/include/metadata.h > new file mode 100644 > index 000000000000..b929bc469b73 > --- /dev/null > +++ b/drivers/fpga/xrt/include/metadata.h > @@ -0,0 +1,229 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Header file for Xilinx Runtime (XRT) driver > + * > + * Copyright (C) 2020-2021 Xilinx, Inc. > + * > + * Authors: > + * Lizhi Hou <Lizhi.Hou@xxxxxxxxxx> > + */ > + > +#ifndef _XRT_METADATA_H > +#define _XRT_METADATA_H > + > +#include <linux/device.h> > +#include <linux/vmalloc.h> > +#include <linux/uuid.h> > + > +#define XRT_MD_INVALID_LENGTH (~0UL) > + These #defines could be in alphabetical order Some #define with embedded acronyms could be expanded ex/ XRT_MD_NODE_CMC_REG , what is CMC ? > +#define XRT_MD_PROP_COMPATIBLE "compatible" > +#define XRT_MD_PROP_PF_NUM "pcie_physical_function" > +#define XRT_MD_PROP_BAR_IDX "pcie_bar_mapping" > +#define XRT_MD_PROP_IO_OFFSET "reg" > +#define XRT_MD_PROP_INTERRUPTS "interrupts" > +#define XRT_MD_PROP_INTERFACE_UUID "interface_uuid" > +#define XRT_MD_PROP_LOGIC_UUID "logic_uuid" > +#define XRT_MD_PROP_VERSION_MAJOR "firmware_version_major" > + > +#define XRT_MD_PROP_HWICAP "axi_hwicap" > +#define XRT_MD_PROP_PDI_CONFIG "pdi_config_mem" > + > +#define XRT_MD_NODE_ENDPOINTS "addressable_endpoints" > +#define XRT_MD_INTERFACES_PATH "/interfaces" > + > +#define XRT_MD_NODE_FIRMWARE "firmware" > +#define XRT_MD_NODE_INTERFACES "interfaces" > +#define XRT_MD_NODE_PARTITION_INFO "partition_info" > + > +#define XRT_MD_NODE_FLASH "ep_card_flash_program_00" > +#define XRT_MD_NODE_XVC_PUB "ep_debug_bscan_user_00" > +#define XRT_MD_NODE_XVC_PRI "ep_debug_bscan_mgmt_00" > +#define XRT_MD_NODE_SYSMON "ep_cmp_sysmon_00" > +#define XRT_MD_NODE_AF_BLP_CTRL_MGMT "ep_firewall_blp_ctrl_mgmt_00" > +#define XRT_MD_NODE_AF_BLP_CTRL_USER "ep_firewall_blp_ctrl_user_00" > +#define XRT_MD_NODE_AF_CTRL_MGMT "ep_firewall_ctrl_mgmt_00" > +#define XRT_MD_NODE_AF_CTRL_USER "ep_firewall_ctrl_user_00" > +#define XRT_MD_NODE_AF_CTRL_DEBUG "ep_firewall_ctrl_debug_00" > +#define XRT_MD_NODE_AF_DATA_H2C "ep_firewall_data_h2c_00" > +#define XRT_MD_NODE_AF_DATA_C2H "ep_firewall_data_c2h_00" > +#define XRT_MD_NODE_AF_DATA_P2P "ep_firewall_data_p2p_00" > +#define XRT_MD_NODE_AF_DATA_M2M "ep_firewall_data_m2m_00" > +#define XRT_MD_NODE_CMC_REG "ep_cmc_regmap_00" > +#define XRT_MD_NODE_CMC_RESET "ep_cmc_reset_00" > +#define XRT_MD_NODE_CMC_MUTEX "ep_cmc_mutex_00" > +#define XRT_MD_NODE_CMC_FW_MEM "ep_cmc_firmware_mem_00" > +#define XRT_MD_NODE_ERT_FW_MEM "ep_ert_firmware_mem_00" > +#define XRT_MD_NODE_ERT_CQ_MGMT "ep_ert_command_queue_mgmt_00" > +#define XRT_MD_NODE_ERT_CQ_USER "ep_ert_command_queue_user_00" > +#define XRT_MD_NODE_MAILBOX_MGMT "ep_mailbox_mgmt_00" > +#define XRT_MD_NODE_MAILBOX_USER "ep_mailbox_user_00" > +#define XRT_MD_NODE_GATE_PLP "ep_pr_isolate_plp_00" > +#define XRT_MD_NODE_GATE_ULP "ep_pr_isolate_ulp_00" > +#define XRT_MD_NODE_PCIE_MON "ep_pcie_link_mon_00" > +#define XRT_MD_NODE_DDR_CALIB "ep_ddr_mem_calib_00" > +#define XRT_MD_NODE_CLK_KERNEL1 "ep_aclk_kernel_00" > +#define XRT_MD_NODE_CLK_KERNEL2 "ep_aclk_kernel_01" > +#define XRT_MD_NODE_CLK_KERNEL3 "ep_aclk_hbm_00" > +#define XRT_MD_NODE_KDMA_CTRL "ep_kdma_ctrl_00" > +#define XRT_MD_NODE_FPGA_CONFIG "ep_fpga_configuration_00" > +#define XRT_MD_NODE_ERT_SCHED "ep_ert_sched_00" > +#define XRT_MD_NODE_XDMA "ep_xdma_00" > +#define XRT_MD_NODE_MSIX "ep_msix_00" > +#define XRT_MD_NODE_QDMA "ep_qdma_00" > +#define XRT_MD_XRT_MD_NODE_QDMA4 "ep_qdma4_00" > +#define XRT_MD_NODE_STM "ep_stream_traffic_manager_00" > +#define XRT_MD_NODE_STM4 "ep_stream_traffic_manager4_00" > +#define XRT_MD_NODE_CLK_SHUTDOWN "ep_aclk_shutdown_00" > +#define XRT_MD_NODE_ERT_BASE "ep_ert_base_address_00" > +#define XRT_MD_NODE_ERT_RESET "ep_ert_reset_00" > +#define XRT_MD_NODE_CLKFREQ_K1 "ep_freq_cnt_aclk_kernel_00" > +#define XRT_MD_NODE_CLKFREQ_K2 "ep_freq_cnt_aclk_kernel_01" > +#define XRT_MD_NODE_CLKFREQ_HBM "ep_freq_cnt_aclk_hbm_00" > +#define XRT_MD_NODE_GAPPING "ep_gapping_demand_00" > +#define XRT_MD_NODE_UCS_CONTROL_STATUS "ep_ucs_control_status_00" > +#define XRT_MD_NODE_P2P "ep_p2p_00" > +#define XRT_MD_NODE_REMAP_P2P "ep_remap_p2p_00" > +#define XRT_MD_NODE_DDR4_RESET_GATE "ep_ddr_mem_srsr_gate_00" > +#define XRT_MD_NODE_ADDR_TRANSLATOR "ep_remap_data_c2h_00" > +#define XRT_MD_NODE_MAILBOX_XRT "ep_mailbox_user_to_ert_00" > +#define XRT_MD_NODE_PMC_INTR "ep_pmc_intr_00" > +#define XRT_MD_NODE_PMC_MUX "ep_pmc_mux_00" > + > +/* driver defined endpoints */ > +#define XRT_MD_NODE_VSEC "drv_ep_vsec_00" > +#define XRT_MD_NODE_VSEC_GOLDEN "drv_ep_vsec_golden_00" > +#define XRT_MD_NODE_BLP_ROM "drv_ep_blp_rom_00" > +#define XRT_MD_NODE_MAILBOX_VSEC "ep_mailbox_vsec_00" > +#define XRT_MD_NODE_PLAT_INFO "drv_ep_platform_info_mgmt_00" > +#define XRT_MD_NODE_TEST "drv_ep_test_00" > +#define XRT_MD_NODE_MGMT_MAIN "drv_ep_mgmt_main_00" > +#define XRT_MD_NODE_FLASH_VSEC "drv_ep_card_flash_program_00" > +#define XRT_MD_NODE_GOLDEN_VER "drv_ep_golden_ver_00" > +#define XRT_MD_XRT_MD_NODE_PARTITION_INFO_BLP "partition_info_0" > +#define XRT_MD_XRT_MD_NODE_PARTITION_INFO_PLP "partition_info_1" > + > +#define XRT_MD_NODE_DDR_SRSR "drv_ep_ddr_srsr" > +#define XRT_MD_REGMAP_DDR_SRSR "drv_ddr_srsr" > + > +#define XRT_MD_PROP_OFFSET "drv_offset" > +#define XRT_MD_PROP_CLK_FREQ "drv_clock_frequency" > +#define XRT_MD_PROP_CLK_CNT "drv_clock_frequency_counter" > +#define XRT_MD_PROP_VBNV "vbnv" > +#define XRT_MD_PROP_VROM "vrom" > +#define XRT_MD_PROP_PARTITION_LEVEL "partition_level" > + > +struct xrt_md_endpoint { > + const char *ep_name; > + u32 bar; > + long bar_off; > + ulong size; > + char *regmap; > + char *regmap_ver; > +}; could the existing 'struct regmap' be used here ? > + > +/* Note: res_id is defined by leaf driver and must start with 0. */ > +struct xrt_iores_map { > + char *res_name; > + int res_id; > +}; > + > +static inline int xrt_md_res_name2id(const struct xrt_iores_map *res_map, > + int entry_num, const char *res_name) > +{ > + int i; > + > + for (i = 0; i < entry_num; i++) { > + if (!strcmp(res_name, res_map->res_name)) Use the 'n' variant strncmp for better safety. Fix generally. > + return res_map->res_id; > + res_map++; > + } > + return -1; > +} > + > +static inline const char * > +xrt_md_res_id2name(const struct xrt_iores_map *res_map, int entry_num, int id) > +{ > + int i; > + > + for (i = 0; i < entry_num; i++) { > + if (res_map->res_id == id) > + return res_map->res_name; > + res_map++; > + } > + return NULL; > +} > + > +unsigned long xrt_md_size(struct device *dev, const char *blob); > +int xrt_md_create(struct device *dev, char **blob); > +int xrt_md_add_endpoint(struct device *dev, char *blob, > + struct xrt_md_endpoint *ep); > +int xrt_md_del_endpoint(struct device *dev, char *blob, const char *ep_name, > + char *regmap_name); > +int xrt_md_get_prop(struct device *dev, const char *blob, const char *ep_name, > + const char *regmap_name, const char *prop, > + const void **val, int *size); > +int xrt_md_set_prop(struct device *dev, char *blob, const char *ep_name, > + const char *regmap_name, const char *prop, > + const void *val, int size); > +int xrt_md_copy_endpoint(struct device *dev, char *blob, const char *src_blob, > + const char *ep_name, const char *regmap_name, > + const char *new_ep_name); > +int xrt_md_get_next_endpoint(struct device *dev, const char *blob, > + const char *ep_name, const char *regmap_name, > + char **next_ep, char **next_regmap); > +int xrt_md_get_compatible_endpoint(struct device *dev, const char *blob, > + const char *regmap_name, const char **ep_name); > +int xrt_md_find_endpoint(struct device *dev, const char *blob, > + const char *ep_name, const char *regmap_name, > + const char **epname); > +void xrt_md_pack(struct device *dev, char *blob); > +char *xrt_md_dup(struct device *dev, const char *blob); > +int xrt_md_get_intf_uuids(struct device *dev, const char *blob, > + u32 *num_uuids, uuid_t *intf_uuids); > +static inline int xrt_md_copy_all_endpoints(struct device *dev, char *blob, const char *src_blob) > +{ > + return xrt_md_copy_endpoint(dev, blob, src_blob, XRT_MD_NODE_ENDPOINTS, > + NULL, NULL); A wrapping a single call seems like an unnecessary abstraction layer. can this be reduced/removed ? > +} > + > +/* > + * Firmware provides 128 bit hash string as unque id of partition/interface. The firmware provides a 128 bit hash string as a unique id to the partition/interface. Existing hw does not yet use the cononical form, so it is necessary to use a translation function. > + * This string will be canonical textual representation in the future. > + * Before that, introducing these two functions below to translate > + * hash string to uuid_t for released hardware. Is there an existing version string the new hw will use to check which way to go ? > + */ > +static inline void xrt_md_trans_uuid2str(const uuid_t *uuid, char *uuidstr) > +{ > + int i, p; > + u8 *u = (u8 *)uuid; > + > + for (p = 0, i = sizeof(uuid_t) - 1; i >= 0; p++, i--) This loop needs to be improved. Consider if sizeof(uuid_t) changed, accessing u[] would overflow. > + (void)snprintf(&uuidstr[p * 2], 3, "%02x", u[i]); (void) cast isn't needed. > +} > + > +static inline int xrt_md_trans_str2uuid(struct device *dev, const char *uuidstr, uuid_t *p_uuid) > +{ > + char *p; > + const char *str; > + char tmp[3] = { 0 }; > + int i, ret; > + > + memset(p_uuid, 0, sizeof(*p_uuid)); > + p = (char *)p_uuid; access with p_uuid->b[] would remove use of 'p' > + str = uuidstr + strlen(uuidstr) - 2; > + > + for (i = 0; i < sizeof(*p_uuid) && str >= uuidstr; i++) { is not filling p_uuid completely really ok ? > + tmp[0] = *str; > + tmp[1] = *(str + 1); > + ret = kstrtou8(tmp, 16, p); > + if (ret) > + return -EINVAL; > + p++; > + str -= 2; > + } > + > + return 0; > +} > + > +#endif > diff --git a/drivers/fpga/xrt/metadata/metadata.c b/drivers/fpga/xrt/metadata/metadata.c > new file mode 100644 > index 000000000000..5d106396f438 > --- /dev/null > +++ b/drivers/fpga/xrt/metadata/metadata.c > @@ -0,0 +1,524 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Xilinx Alveo FPGA Metadata parse APIs > + * > + * Copyright (C) 2020-2021 Xilinx, Inc. > + * > + * Authors: > + * Lizhi Hou <Lizhi.Hou@xxxxxxxxxx> > + */ > + > +#include <linux/libfdt_env.h> > +#include "libfdt.h" > +#include "metadata.h" > + > +#define MAX_BLOB_SIZE (4096 * 25) > + > +static int xrt_md_setprop(struct device *dev, char *blob, int offset, > + const char *prop, const void *val, int size); > +static int xrt_md_overlay(struct device *dev, char *blob, int target, > + const char *overlay_blob, int overlay_offset); > +static int xrt_md_get_endpoint(struct device *dev, const char *blob, > + const char *ep_name, const char *regmap_name, > + int *ep_offset); consider reordering functions so these fwd decl's are not needed > + > +unsigned long xrt_md_size(struct device *dev, const char *blob) > +{ > + unsigned long len = (long)fdt_totalsize(blob); > + > + len = (len > MAX_BLOB_SIZE) ? XRT_MD_INVALID_LENGTH : len; > + return len; > +} > +EXPORT_SYMBOL_GPL(xrt_md_size); > + > +int xrt_md_create(struct device *dev, char **blob) > +{ > + int ret = 0; > + > + WARN_ON(!blob); > + > + *blob = vmalloc(MAX_BLOB_SIZE); why vmalloc instead of vzalloc ? > + if (!*blob) > + return -ENOMEM; > + > + ret = fdt_create_empty_tree(*blob, MAX_BLOB_SIZE); > + if (ret) { > + dev_err(dev, "format blob failed, ret = %d", ret); > + goto failed; > + } > + > + ret = fdt_next_node(*blob, -1, NULL); A variable called 'offset' would make more sense here because it is used later in fdt_add_subnode as the parentoffset parameter. > + if (ret < 0) { > + dev_err(dev, "No Node, ret = %d", ret); > + goto failed; > + } > + > + ret = fdt_add_subnode(*blob, ret, XRT_MD_NODE_ENDPOINTS); why isn't the parentoffset '0' ? > + if (ret < 0) { > + dev_err(dev, "add node failed, ret = %d", ret); > + goto failed; > + } > + > + return 0; > + > +failed: > + vfree(*blob); > + *blob = NULL; > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(xrt_md_create); > + > +static int xrt_md_add_node(struct device *dev, char *blob, int parent_offset, > + const char *ep_name) > +{ > + int ret; > + > + ret = fdt_add_subnode(blob, parent_offset, ep_name); > + if (ret < 0 && ret != -FDT_ERR_EXISTS) > + dev_err(dev, "failed to add node %s. %d", ep_name, ret); > + > + return ret; > +} > + > +int xrt_md_del_endpoint(struct device *dev, char *blob, const char *ep_name, > + char *regmap_name) > +{ > + int ret; > + int ep_offset; > + > + ret = xrt_md_get_endpoint(dev, blob, ep_name, regmap_name, &ep_offset); > + if (ret) { > + dev_err(dev, "can not find ep %s", ep_name); > + return -EINVAL; > + } > + > + ret = fdt_del_node(blob, ep_offset); > + if (ret) > + dev_err(dev, "delete node %s failed, ret %d", ep_name, ret); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(xrt_md_del_endpoint); > + > +static int __xrt_md_add_endpoint(struct device *dev, char *blob, > + struct xrt_md_endpoint *ep, int *offset, bool root) > +{ > + int ret = 0; > + int ep_offset = 0; > + u32 val, count = 0; > + u64 io_range[2]; > + char comp[128]; > + > + if (!ep->ep_name) { > + dev_err(dev, "empty name"); > + return -EINVAL; > + } > + > + if (!root) { > + ret = xrt_md_get_endpoint(dev, blob, XRT_MD_NODE_ENDPOINTS, NULL, > + &ep_offset); > + if (ret) { > + dev_err(dev, "invalid blob, ret = %d", ret); > + return -EINVAL; > + } > + } > + > + ep_offset = xrt_md_add_node(dev, blob, ep_offset, ep->ep_name); > + if (ep_offset < 0) { > + dev_err(dev, "add endpoint failed, ret = %d", ret); > + return -EINVAL; > + } > + if (offset) > + *offset = ep_offset; > + > + if (ep->size != 0) { > + val = cpu_to_be32(ep->bar); > + ret = xrt_md_setprop(dev, blob, ep_offset, XRT_MD_PROP_BAR_IDX, > + &val, sizeof(u32)); > + if (ret) { > + dev_err(dev, "set %s failed, ret %d", > + XRT_MD_PROP_BAR_IDX, ret); > + goto failed; > + } > + io_range[0] = cpu_to_be64((u64)ep->bar_off); > + io_range[1] = cpu_to_be64((u64)ep->size); is there a type mismatch between bar (u32) and size (u64) ? > + ret = xrt_md_setprop(dev, blob, ep_offset, XRT_MD_PROP_IO_OFFSET, > + io_range, sizeof(io_range)); > + if (ret) { > + dev_err(dev, "set %s failed, ret %d", > + XRT_MD_PROP_IO_OFFSET, ret); > + goto failed; > + } > + } > + > + if (ep->regmap) { > + if (ep->regmap_ver) { > + count = snprintf(comp, sizeof(comp), > + "%s-%s", ep->regmap, ep->regmap_ver); > + count++; > + } > + > + count += snprintf(comp + count, sizeof(comp) - count, > + "%s", ep->regmap); > + count++; unlikely, but overflow is not checked. are multiple null's in this string ok ? > + > + ret = xrt_md_setprop(dev, blob, ep_offset, XRT_MD_PROP_COMPATIBLE, > + comp, count); > + if (ret) { > + dev_err(dev, "set %s failed, ret %d", > + XRT_MD_PROP_COMPATIBLE, ret); > + goto failed; > + } > + } > + > +failed: > + if (ret) > + xrt_md_del_endpoint(dev, blob, ep->ep_name, NULL); > + > + return ret; > +} > + > +int xrt_md_add_endpoint(struct device *dev, char *blob, > + struct xrt_md_endpoint *ep) > +{ > + return __xrt_md_add_endpoint(dev, blob, ep, NULL, false); ok, user doesn't add root's endpoint. could an assert be added ? > +} > +EXPORT_SYMBOL_GPL(xrt_md_add_endpoint); > + > +static int xrt_md_get_endpoint(struct device *dev, const char *blob, > + const char *ep_name, const char *regmap_name, > + int *ep_offset) > +{ > + int offset; > + const char *name; > + > + for (offset = fdt_next_node(blob, -1, NULL); > + offset >= 0; > + offset = fdt_next_node(blob, offset, NULL)) { > + name = fdt_get_name(blob, offset, NULL); > + if (!name || strncmp(name, ep_name, strlen(ep_name) + 1)) strlen() + 1 ? > + continue; > + if (!regmap_name || > + !fdt_node_check_compatible(blob, offset, regmap_name)) > + break; > + } > + if (offset < 0) > + return -ENODEV; > + > + *ep_offset = offset; > + > + return 0; > +} > + > +int xrt_md_find_endpoint(struct device *dev, const char *blob, > + const char *ep_name, const char *regmap_name, > + const char **epname) > +{ > + int offset; > + int ret; > + > + ret = xrt_md_get_endpoint(dev, blob, ep_name, regmap_name, > + &offset); > + if (!ret && epname && offset >= 0) The offset >= 0 check isn't needed, !ret is enough > + *epname = fdt_get_name(blob, offset, NULL); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(xrt_md_find_endpoint); > + > +int xrt_md_get_prop(struct device *dev, const char *blob, const char *ep_name, > + const char *regmap_name, const char *prop, > + const void **val, int *size) > +{ > + int offset; > + int ret; > + > + if (val) > + *val = NULL; Seems like no point in making this call if !val Return -EINVAL if !val and remove the if (val) check below. > + if (ep_name) { > + ret = xrt_md_get_endpoint(dev, blob, ep_name, regmap_name, > + &offset); > + if (ret) { > + dev_err(dev, "cannot get ep %s, regmap %s, ret = %d", > + ep_name, regmap_name, ret); > + return -EINVAL; > + } > + } else { > + offset = fdt_next_node(blob, -1, NULL); > + if (offset < 0) { > + dev_err(dev, "internal error, ret = %d", offset); > + return -EINVAL; > + } > + } > + > + if (val) { > + *val = fdt_getprop(blob, offset, prop, size); > + if (!*val) { > + dev_dbg(dev, "get ep %s, prop %s failed", ep_name, prop); > + return -EINVAL; > + } > + } > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(xrt_md_get_prop); > + > +static int xrt_md_setprop(struct device *dev, char *blob, int offset, > + const char *prop, const void *val, int size) > +{ > + int ret; > + > + ret = fdt_setprop(blob, offset, prop, val, size); > + if (ret) > + dev_err(dev, "failed to set prop %d", ret); > + > + return ret; > +} > + > +int xrt_md_set_prop(struct device *dev, char *blob, > + const char *ep_name, const char *regmap_name, > + const char *prop, const void *val, int size) > +{ > + int offset; > + int ret; > + > + if (ep_name) { > + ret = xrt_md_get_endpoint(dev, blob, ep_name, > + regmap_name, &offset); > + if (ret) { > + dev_err(dev, "cannot get node %s, ret = %d", > + ep_name, ret); > + return -EINVAL; > + } > + } else { > + offset = fdt_next_node(blob, -1, NULL); > + if (offset < 0) { > + dev_err(dev, "internal error, ret = %d", offset); > + return -EINVAL; > + } > + } This if-else block is a cut-n-paste from above. It is good to convert common logic blocks to macros or inline functions. > + > + ret = xrt_md_setprop(dev, blob, offset, prop, val, size); > + if (ret) > + dev_err(dev, "set prop %s failed, ret = %d", prop, ret); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(xrt_md_set_prop); > + > +int xrt_md_copy_endpoint(struct device *dev, char *blob, const char *src_blob, > + const char *ep_name, const char *regmap_name, > + const char *new_ep_name) > +{ > + int offset, target; > + int ret; > + struct xrt_md_endpoint ep = {0}; > + const char *newepnm = new_ep_name ? new_ep_name : ep_name; How is this valid ? The xrt_md_get_endpoint searches by ep_name and if there names are not unique the second one will never be found. > + > + ret = xrt_md_get_endpoint(dev, src_blob, ep_name, regmap_name, > + &offset); > + if (ret) > + return -EINVAL; > + > + ret = xrt_md_get_endpoint(dev, blob, newepnm, regmap_name, &target); > + if (ret) { > + ep.ep_name = newepnm; > + ret = __xrt_md_add_endpoint(dev, blob, &ep, &target, > + fdt_parent_offset(src_blob, offset) == 0); > + if (ret) > + return -EINVAL; > + } > + > + ret = xrt_md_overlay(dev, blob, target, src_blob, offset); > + if (ret) > + dev_err(dev, "overlay failed, ret = %d", ret); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(xrt_md_copy_endpoint); > + > +char *xrt_md_dup(struct device *dev, const char *blob) > +{ > + int ret; > + char *dup_blob; > + > + ret = xrt_md_create(dev, &dup_blob); > + if (ret) > + return NULL; > + ret = xrt_md_overlay(dev, dup_blob, -1, blob, -1); would memcpy-ing the blob work ? > + if (ret) { > + vfree(dup_blob); > + return NULL; > + } > + > + return dup_blob; > +} > +EXPORT_SYMBOL_GPL(xrt_md_dup); > + > +static int xrt_md_overlay(struct device *dev, char *blob, int target, > + const char *overlay_blob, int overlay_offset) > +{ > + int property, subnode; > + int ret; > + > + WARN_ON(!blob || !overlay_blob); > + > + if (!blob) { > + dev_err(dev, "blob is NULL"); > + return -EINVAL; > + } > + > + if (target < 0) { > + target = fdt_next_node(blob, -1, NULL); > + if (target < 0) { > + dev_err(dev, "invalid target"); > + return -EINVAL; > + } > + } > + if (overlay_offset < 0) { > + overlay_offset = fdt_next_node(overlay_blob, -1, NULL); > + if (overlay_offset < 0) { > + dev_err(dev, "invalid overlay"); > + return -EINVAL; > + } > + } > + > + fdt_for_each_property_offset(property, overlay_blob, overlay_offset) { > + const char *name; > + const void *prop; > + int prop_len; > + > + prop = fdt_getprop_by_offset(overlay_blob, property, &name, > + &prop_len); > + if (!prop || prop_len >= MAX_BLOB_SIZE) { could add prop_len < 0 as another sanity check > + dev_err(dev, "internal error"); > + return -EINVAL; > + } > + > + ret = xrt_md_setprop(dev, blob, target, name, prop, > + prop_len); > + if (ret) { > + dev_err(dev, "setprop failed, ret = %d", ret); > + return ret; overlay_blob is half done, as an error handling shouldn't it be undone ? > + } > + } > + > + fdt_for_each_subnode(subnode, overlay_blob, overlay_offset) { > + const char *name = fdt_get_name(overlay_blob, subnode, NULL); > + int nnode; > + > + nnode = xrt_md_add_node(dev, blob, target, name); > + if (nnode == -FDT_ERR_EXISTS) > + nnode = fdt_subnode_offset(blob, target, name); > + if (nnode < 0) { > + dev_err(dev, "add node failed, ret = %d", nnode); > + return nnode; > + } > + > + ret = xrt_md_overlay(dev, blob, nnode, overlay_blob, subnode); eek, recursion. Any chance this will blow the stack ? > + if (ret) > + return ret; > + } > + > + return 0; > +} > + > +int xrt_md_get_next_endpoint(struct device *dev, const char *blob, > + const char *ep_name, const char *regmap_name, > + char **next_ep, char **next_regmap) > +{ > + int offset, ret; > + > + if (!ep_name) { > + ret = xrt_md_get_endpoint(dev, blob, XRT_MD_NODE_ENDPOINTS, NULL, > + &offset); > + } else { > + ret = xrt_md_get_endpoint(dev, blob, ep_name, regmap_name, > + &offset); > + } > + > + if (ret) { > + *next_ep = NULL; > + *next_regmap = NULL; could initialize next_ep and next_regmap to NULL outside the check. > + return -EINVAL; > + } > + > + offset = ep_name ? fdt_next_subnode(blob, offset) : > + fdt_first_subnode(blob, offset); > + if (offset < 0) { > + *next_ep = NULL; > + *next_regmap = NULL; > + return -EINVAL; > + } > + > + *next_ep = (char *)fdt_get_name(blob, offset, NULL); > + *next_regmap = (char *)fdt_stringlist_get(blob, offset, XRT_MD_PROP_COMPATIBLE, > + 0, NULL); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(xrt_md_get_next_endpoint); > + > +int xrt_md_get_compatible_endpoint(struct device *dev, const char *blob, > + const char *regmap_name, const char **ep_name) > +{ > + int ep_offset; > + > + ep_offset = fdt_node_offset_by_compatible(blob, -1, regmap_name); > + if (ep_offset < 0) { > + *ep_name = NULL; > + return -ENOENT; > + } > + > + *ep_name = (char *)fdt_get_name(blob, ep_offset, NULL); why the cast ? > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(xrt_md_get_compatible_endpoint); > + > +void xrt_md_pack(struct device *dev, char *blob) > +{ > + int ret; > + > + ret = fdt_pack(blob); > + if (ret) > + dev_err(dev, "pack failed %d", ret); maybe return int > +} > +EXPORT_SYMBOL_GPL(xrt_md_pack); > + The input/output of num_uuids parameter is tricky add a comment > +int xrt_md_get_intf_uuids(struct device *dev, const char *blob, > + u32 *num_uuids, uuid_t *intf_uuids) what is intf ? change to 'interface' ? > +{ > + int offset, count = 0; > + int ret; > + const char *uuid_str; > + > + ret = xrt_md_get_endpoint(dev, blob, XRT_MD_NODE_INTERFACES, NULL, &offset); > + if (ret) > + return -ENOENT; > + > + for (offset = fdt_first_subnode(blob, offset); > + offset >= 0; > + offset = fdt_next_subnode(blob, offset)) { > + uuid_str = fdt_getprop(blob, offset, XRT_MD_PROP_INTERFACE_UUID, > + NULL); > + if (!uuid_str) { > + dev_err(dev, "empty intf uuid node"); > + return -EINVAL; > + } > + > + if (intf_uuids && count < *num_uuids) { > + ret = xrt_md_trans_str2uuid(dev, uuid_str, > + &intf_uuids[count]); > + if (ret) > + return -EINVAL; > + } > + count++; keep going even when count > num_uuids ? that seems like an error. Tom > + } > + > + *num_uuids = count; > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(xrt_md_get_intf_uuids);