On 2/12/24 22:15, Timur Tabi wrote:
Add the NVreg_RegistryDwords command line parameter, which allows
specifying additional registry keys to be sent to GSP-RM. This
allows additional configuration, debugging, and experimentation
with GSP-RM, which uses these keys to alter its behavior.
Note that these keys are passed as-is to GSP-RM, and Nouveau does
not parse them. This is in contrast to the Nvidia driver, which may
parse some of the keys to configure some functionality in concert with
GSP-RM. Therefore, any keys which also require action by the driver
may not function correctly when passed by Nouveau. Caveat emptor.
The name and format of NVreg_RegistryDwords is the same as used by
the Nvidia driver, to maintain compatibility.
Signed-off-by: Timur Tabi <ttabi@xxxxxxxxxx>
---
v3: rebased to drm-next
.../gpu/drm/nouveau/include/nvkm/subdev/gsp.h | 6 +
.../gpu/drm/nouveau/nvkm/subdev/gsp/r535.c | 279 ++++++++++++++++--
2 files changed, 261 insertions(+), 24 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h b/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
index 6f5d376d8fcc..3fbc57b16a05 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
@@ -211,6 +211,12 @@ struct nvkm_gsp {
struct mutex mutex;;
struct idr idr;
} client_id;
+
+ /* A linked list of registry items. The registry RPC will be built from it. */
+ struct list_head registry_list;
+
+ /* The size of the registry RPC */
+ size_t registry_rpc_size;
};
static inline bool
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
index 1c46e3f919be..86b62c7e1229 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
@@ -54,6 +54,8 @@
#include <nvrm/535.113.01/nvidia/kernel/inc/vgpu/rpc_global_enums.h>
#include <linux/acpi.h>
+#include <linux/ctype.h>
+#include <linux/parser.h>
#define GSP_MSG_MIN_SIZE GSP_PAGE_SIZE
#define GSP_MSG_MAX_SIZE GSP_PAGE_MIN_SIZE * 16
@@ -1082,51 +1084,280 @@ r535_gsp_rpc_unloading_guest_driver(struct nvkm_gsp *gsp, bool suspend)
return nvkm_gsp_rpc_wr(gsp, rpc, true);
}
+struct registry_list_entry {
+ struct list_head list;
Nit: 'head' or 'entry' might be more suitable.
+ size_t name_len;
+ u32 type;
I prefer to represent type as enum or use a define for '1 = integer' instead.
This also gets you rid of the need to explicitly explain it's meaning in the
documentation of add_registry().
+ u32 data;
+ u32 length;
+ char name[];
+};
+
+/**
+ * add_registry -- adds a registry entry
+ * @gsp: gsp pointer
+ * @name: name of the registry key
+ * @type: type of data (1 = integer)
+ * @data: value
+ * @length: size of data, in bytes
+ *
+ * Adds a registry key/value pair to the registry database.
+ *
+ * Currently, only 32-bit integers (type == 1, length == 4) are supported.
What if we pass something else? This function doesn't seem to ensure nothing
else is accepted. Although I recognize that it's only used by add_registry_num()
enforcing this limitation by it's function signature.
+ *
+ * This function collects the registry information in a linked list. After
+ * all registry keys have been added, build_registry() is used to create the
+ * RPC data structure.
+ *
+ * registry_rpc_size is a running total of the size of all registry keys.
+ * It's used to avoid an O(n) calculation of the size when the RPC is built.
+ *
+ * Returns 0 on success, or negative error code on error.
+ */
+static int add_registry(struct nvkm_gsp *gsp, const char *name, u32 type, u32 data, u32 length)
+{
+ struct registry_list_entry *reg;
+ size_t nlen = strlen(name) + 1;
+
+ /* Set an arbitrary limit to avoid problems with broken command lines */
+ if (strlen(name) > 64)
Could re-use nlen for this check.
+ return -EFBIG;
This error code doesn't seem to apply here, prefer EINVAL.
+
+ reg = kmalloc(sizeof(struct registry_list_entry) + nlen, GFP_KERNEL);
+ if (!reg)
+ return -ENOMEM;
+
+ memcpy(reg->name, name, nlen);
+ reg->name_len = nlen;
+ reg->type = type;
+ reg->data = data;
+ reg->length = length;
+
+ nvkm_debug(&gsp->subdev, "adding GSP-RM registry '%s=%u'\n", name, data);
+ list_add_tail(®->list, &gsp->registry_list);
+ gsp->registry_rpc_size += sizeof(PACKED_REGISTRY_ENTRY) + nlen;
+
+ return 0;
+}
+
+static int add_registry_num(struct nvkm_gsp *gsp, const char *name, u32 value)
+{
+ return add_registry(gsp, name, 1, value, sizeof(u32));
+}
+
+/**
+ * build_registry -- create the registry RPC data
+ * @gsp: gsp pointer
+ * @registry: pointer to the RPC payload to fill
+ *
+ * After all registry key/value pairs have been added, call this function to
+ * build the RPC.
+ *
+ * The registry RPC looks like this:
+ *
+ * +-----------------+
+ * |NvU32 size; |
+ * |NvU32 numEntries;|
+ * +-----------------+
+ * +---------------------+
+ * |PACKED_REGISTRY_ENTRY|
+ * +---------------------+
+ * |PACKED_REGISTRY_ENTRY|
+ * +---------------------+
+ * ... (one copy for each entry)
+ *
+ * +----------------------------------+
+ * |Null-terminated string for entry 0|
+ * +----------------------------------+
+ * |Null-terminated string for entry 1|
+ * +----------------------------------+
+ * ... (one copy for each entry)
+ *
+ * All memory allocated by add_registry() is released.
+ */
+static void build_registry(struct nvkm_gsp *gsp, PACKED_REGISTRY_TABLE *registry)
+{
+ struct registry_list_entry *reg, *n;
+ size_t str_offset;
+ unsigned int i = 0;
+
+ registry->numEntries = list_count_nodes(&gsp->registry_list);
+ str_offset = struct_size(registry, entries, registry->numEntries);
+
+ list_for_each_entry_safe(reg, n, &gsp->registry_list, list) {
+ registry->entries[i].type = reg->type;
+ registry->entries[i].data = reg->data;
+ registry->entries[i].length = reg->length;
+ registry->entries[i].nameOffset = str_offset;
+ memcpy((void *)registry + str_offset, reg->name, reg->name_len);
+ str_offset += reg->name_len;
+ i++;
+
+ list_del(®->list);
+ kfree(reg);
+ }
+
+ /* Double-check that we calculated the sizes correctly */
+ WARN_ON(gsp->registry_rpc_size != str_offset);
+
+ registry->size = gsp->registry_rpc_size;
+}
+
+/**
+ * clean_registry -- clean up registry memory in case of error
+ * @gsp: gsp pointer
+ *
+ * Call this function to clean up all memory allocated by add_registry()
+ * in case of error and build_registry() is not called.
+ */
+static void clean_registry(struct nvkm_gsp *gsp)
+{
+ struct registry_list_entry *reg, *n;
+
+ list_for_each_entry_safe(reg, n, &gsp->registry_list, list) {
+ list_del(®->list);
+ kfree(reg);
+ }
+
+ gsp->registry_rpc_size = sizeof(PACKED_REGISTRY_TABLE);
+}
+
+MODULE_PARM_DESC(NVreg_RegistryDwords,
+ "A semicolon-separated list of key=integer pairs of GSP-RM registry keys");
+static char *NVreg_RegistryDwords;
+module_param(NVreg_RegistryDwords, charp, 0400);
+
/* dword only */
struct nv_gsp_registry_entries {
const char *name;
u32 value;
};
+/**
+ * r535_registry_entries - required registry entries for GSP-RM
+ *
+ * This array lists registry entries that are required for GSP-RM to
+ * function correctly.
+ *
+ * RMSecBusResetEnable - enables PCI secondary bus reset
+ * RMForcePcieConfigSave - forces GSP-RM to preserve PCI configuration
+ * registers on any PCI reset.
+ */
static const struct nv_gsp_registry_entries r535_registry_entries[] = {
{ "RMSecBusResetEnable", 1 },
{ "RMForcePcieConfigSave", 1 },
};
#define NV_GSP_REG_NUM_ENTRIES ARRAY_SIZE(r535_registry_entries)
+/**
+ * strip - strips all characters in 'reject' from 's'
+ * @s: string to strip
+ * @reject: string of characters to remove
+ *
+ * 's' is modified.
+ *
+ * Returns the length of the new string.
+ */
+static size_t strip(char *s, const char *reject)
+{
+ char *p = s, *p2 = s;
+ size_t length = 0;
+ char c;
+
+ do {
+ while ((c = *p2) && strchr(reject, c))
+ p2++;
+
+ *p++ = c = *p2++;
+ length++;
+ } while (c);
+
+ return length;
+}
+
+/**
+ * r535_gsp_rpc_set_registry - build registry RPC and call GSP-RM
+ * @gsp: gsp pointer
+ *
+ * The GSP-RM registry is a set of key/value pairs that configure some aspects
+ * of GSP-RM. The keys are strings, and the values are 32-bit integers.
+ *
+ * The registry is built from a combination of a static hard-coded list (see
+ * above) and entries passed on the driver's command line.
+ */
static int
r535_gsp_rpc_set_registry(struct nvkm_gsp *gsp)
{
PACKED_REGISTRY_TABLE *rpc;
- char *strings;
- int str_offset;
- int i;
- size_t rpc_size = struct_size(rpc, entries, NV_GSP_REG_NUM_ENTRIES);
+ unsigned int i;
+ int ret;
- /* add strings + null terminator */
- for (i = 0; i < NV_GSP_REG_NUM_ENTRIES; i++)
- rpc_size += strlen(r535_registry_entries[i].name) + 1;
+ INIT_LIST_HEAD(&gsp->registry_list);
+ gsp->registry_rpc_size = sizeof(PACKED_REGISTRY_TABLE);
- rpc = nvkm_gsp_rpc_get(gsp, NV_VGPU_MSG_FUNCTION_SET_REGISTRY, rpc_size);
- if (IS_ERR(rpc))
- return PTR_ERR(rpc);
+ /* Add the required registry entries first */
+ for (i = 0; i < NV_GSP_REG_NUM_ENTRIES; i++) {
+ ret = add_registry_num(gsp, r535_registry_entries[i].name,
+ r535_registry_entries[i].value);
+ if (ret) {
+ clean_registry(gsp);
+ return ret;
+ }
+ }
+
+ /*
+ * The NVreg_RegistryDwords parameter is a string of key=value
+ * pairs separated by semicolons. We need to extract and trim each
+ * substring, and then parse the substring to extract the key and
+ * value.
+ */
+ if (NVreg_RegistryDwords) {
+ char *p = kstrdup(NVreg_RegistryDwords, GFP_KERNEL);
+ char *start, *next = p, *equal;
+ size_t length;
+
+ /* Remove any whitespace from the parameter string */
+ length = strip(p, " \t\n");
+
+ while ((start = strsep(&next, ";"))) {
+ long value;
+
+ equal = strchr(start, '=');
+ if (!equal || (equal == start) || !isdigit(equal[1])) {
+ nvkm_error(&gsp->subdev,
+ "ignoring invalid registry string '%s'\n", start);
+ continue;
+ }
- rpc->numEntries = NV_GSP_REG_NUM_ENTRIES;
+ ret = kstrtol(equal + 1, 0, &value);
+ if (ret) {
+ nvkm_error(&gsp->subdev,
+ "ignoring invalid registry value in '%s'\n", start);
+ continue;
+ }
At a first glance, the string parsing looks correct to me. Did you test with invalid
strings as well?
- str_offset = offsetof(typeof(*rpc), entries[NV_GSP_REG_NUM_ENTRIES]);
- strings = (char *)&rpc->entries[NV_GSP_REG_NUM_ENTRIES];
- for (i = 0; i < NV_GSP_REG_NUM_ENTRIES; i++) {
- int name_len = strlen(r535_registry_entries[i].name) + 1;
-
- rpc->entries[i].nameOffset = str_offset;
- rpc->entries[i].type = 1;
- rpc->entries[i].data = r535_registry_entries[i].value;
- rpc->entries[i].length = 4;
- memcpy(strings, r535_registry_entries[i].name, name_len);
- strings += name_len;
- str_offset += name_len;
+ /* Truncate the key=value string to just key */
+ *equal = 0;
What's the purpose for that?
+
+ ret = add_registry_num(gsp, start, value);
+ if (ret) {
+ nvkm_error(&gsp->subdev,
+ "ignoring invalid registry key/value '%s=%lu'\n",
+ start, value);
+ continue;
+ }
+ }
+
+ kfree(p);
}
- rpc->size = str_offset;
+
+ rpc = nvkm_gsp_rpc_get(gsp, NV_VGPU_MSG_FUNCTION_SET_REGISTRY, gsp->registry_rpc_size);
+ if (IS_ERR(rpc)) {
+ clean_registry(gsp);
+ return PTR_ERR(rpc);
+ }
+
+ build_registry(gsp, rpc);
return nvkm_gsp_rpc_wr(gsp, rpc, false);
}
