*/
#include <linux/bitops.h>
+#include <linux/ctype.h>
#include <linux/configfs.h>
#include <linux/cleanup.h>
#include <linux/find.h>
#include <linux/pci.h>
#include <linux/string.h>
+#include "instructions/xe_mi_commands.h"
#include "xe_configfs.h"
#include "xe_hw_engine_types.h"
#include "xe_module.h"
*
* This attribute can only be set before binding to the device.
*
+ * Context restore BB
+ * ------------------
+ *
+ * Allow to execute a batch buffer during any context switches. When the
+ * GPU is restoring the context, it executes additional commands. It's useful
+ * for testing additional workarounds and validating certain HW behaviors: it's
+ * not intended for normal execution and will taint the kernel with TAINT_TEST
+ * when used.
+ *
+ * Currently this is implemented only for post context restore. Examples:
+ *
+ * #. Execute a LRI command to write 0xDEADBEEF to register 0x4f10::
+ *
+ * # echo 'rcs cmd 11000001 4F100 DEADBEEF' \
+ * > /sys/kernel/config/xe/0000:03:00.0/ctx_restore_post_bb
+ *
+ * #. Load certain values in a couple of registers (it can be used as a simpler
+ * alternative to the `cmd`) action::
+ *
+ * # cat > /sys/kernel/config/xe/0000:03:00.0/ctx_restore_post_bb <<EOF
+ * rcs reg 4F100 DEADBEEF
+ * rcs reg 4F104 FFFFFFFF
+ * EOF
+ *
+ * .. note::
+ *
+ * When using multiple lines, make sure to use a command that is
+ * implemented with a single write syscall, like HEREDOC.
+ *
+ * This attribute can only be set before binding to the device.
+ *
* Remove devices
* ==============
*
* # rmdir /sys/kernel/config/xe/0000:03:00.0/
*/
+/* Similar to struct xe_bb, but not tied to HW (yet) */
+struct wa_bb {
+ u32 *cs;
+ u32 len; /* in dwords */
+};
+
struct xe_config_group_device {
struct config_group group;
struct xe_config_device {
u64 engines_allowed;
+ struct wa_bb ctx_restore_post_bb[XE_ENGINE_CLASS_MAX];
bool survivability_mode;
bool enable_psmi;
} config;
return len;
}
+static bool wa_bb_read_advance(bool dereference, char **p,
+ const char *append, size_t len,
+ size_t *max_size)
+{
+ if (dereference) {
+ if (len >= *max_size)
+ return false;
+ *max_size -= len;
+ if (append)
+ memcpy(*p, append, len);
+ }
+
+ *p += len;
+
+ return true;
+}
+
+static ssize_t wa_bb_show(struct xe_config_group_device *dev,
+ struct wa_bb wa_bb[static XE_ENGINE_CLASS_MAX],
+ char *data, size_t sz)
+{
+ char *p = data;
+
+ guard(mutex)(&dev->lock);
+
+ for (size_t i = 0; i < ARRAY_SIZE(engine_info); i++) {
+ enum xe_engine_class ec = engine_info[i].engine_class;
+ size_t len;
+
+ if (!wa_bb[ec].len)
+ continue;
+
+ len = snprintf(p, sz, "%s:", engine_info[i].cls);
+ if (!wa_bb_read_advance(data, &p, NULL, len, &sz))
+ return -ENOBUFS;
+
+ for (size_t j = 0; j < wa_bb[ec].len; j++) {
+ len = snprintf(p, sz, " %08x", wa_bb[ec].cs[j]);
+ if (!wa_bb_read_advance(data, &p, NULL, len, &sz))
+ return -ENOBUFS;
+ }
+
+ if (!wa_bb_read_advance(data, &p, "\n", 1, &sz))
+ return -ENOBUFS;
+ }
+
+ if (!wa_bb_read_advance(data, &p, "", 1, &sz))
+ return -ENOBUFS;
+
+ /* Reserve one more to match check for '\0' */
+ if (!data)
+ p++;
+
+ return p - data;
+}
+
+static ssize_t ctx_restore_post_bb_show(struct config_item *item, char *page)
+{
+ struct xe_config_group_device *dev = to_xe_config_group_device(item);
+
+ return wa_bb_show(dev, dev->config.ctx_restore_post_bb, page, SZ_4K);
+}
+
+static void wa_bb_append(struct wa_bb *wa_bb, u32 val)
+{
+ if (wa_bb->cs)
+ wa_bb->cs[wa_bb->len] = val;
+
+ wa_bb->len++;
+}
+
+static ssize_t parse_hex(const char *line, u32 *pval)
+{
+ char numstr[12];
+ const char *p;
+ ssize_t numlen;
+
+ p = line + strspn(line, " \t");
+ if (!*p || *p == '\n')
+ return 0;
+
+ numlen = strcspn(p, " \t\n");
+ if (!numlen || numlen >= sizeof(numstr) - 1)
+ return -EINVAL;
+
+ memcpy(numstr, p, numlen);
+ numstr[numlen] = '\0';
+ p += numlen;
+
+ if (kstrtou32(numstr, 16, pval))
+ return -EINVAL;
+
+ return p - line;
+}
+
+/*
+ * Parse lines with the format
+ *
+ * <engine-class> cmd <u32> <u32...>
+ * <engine-class> reg <u32_addr> <u32_val>
+ *
+ * and optionally save them in @wa_bb[i].cs is non-NULL.
+ *
+ * Return the number of dwords parsed.
+ */
+static ssize_t parse_wa_bb_lines(const char *lines,
+ struct wa_bb wa_bb[static XE_ENGINE_CLASS_MAX])
+{
+ ssize_t dwords = 0, ret;
+ const char *p;
+
+ for (p = lines; *p; p++) {
+ const struct engine_info *info = NULL;
+ u32 val, val2;
+
+ /* Also allow empty lines */
+ p += strspn(p, " \t\n");
+ if (!*p)
+ break;
+
+ ret = parse_engine(p, " \t\n", NULL, &info);
+ if (ret < 0)
+ return ret;
+
+ p += ret;
+ p += strspn(p, " \t");
+
+ if (str_has_prefix(p, "cmd")) {
+ for (p += strlen("cmd"); *p;) {
+ ret = parse_hex(p, &val);
+ if (ret < 0)
+ return -EINVAL;
+ if (!ret)
+ break;
+
+ p += ret;
+ dwords++;
+ wa_bb_append(&wa_bb[info->engine_class], val);
+ }
+ } else if (str_has_prefix(p, "reg")) {
+ p += strlen("reg");
+ ret = parse_hex(p, &val);
+ if (ret <= 0)
+ return -EINVAL;
+
+ p += ret;
+ ret = parse_hex(p, &val2);
+ if (ret <= 0)
+ return -EINVAL;
+
+ p += ret;
+ dwords += 3;
+ wa_bb_append(&wa_bb[info->engine_class],
+ MI_LOAD_REGISTER_IMM | MI_LRI_NUM_REGS(1));
+ wa_bb_append(&wa_bb[info->engine_class], val);
+ wa_bb_append(&wa_bb[info->engine_class], val2);
+ } else {
+ return -EINVAL;
+ }
+ }
+
+ return dwords;
+}
+
+static ssize_t wa_bb_store(struct wa_bb wa_bb[static XE_ENGINE_CLASS_MAX],
+ struct xe_config_group_device *dev,
+ const char *page, size_t len)
+{
+ /* tmp_wa_bb must match wa_bb's size */
+ struct wa_bb tmp_wa_bb[XE_ENGINE_CLASS_MAX] = { };
+ ssize_t count, class;
+ u32 *tmp;
+
+ /* 1. Count dwords - wa_bb[i].cs is NULL for all classes */
+ count = parse_wa_bb_lines(page, tmp_wa_bb);
+ if (count < 0)
+ return count;
+
+ guard(mutex)(&dev->lock);
+
+ if (is_bound(dev))
+ return -EBUSY;
+
+ /*
+ * 2. Allocate a u32 array and set the pointers to the right positions
+ * according to the length of each class' wa_bb
+ */
+ tmp = krealloc(wa_bb[0].cs, count * sizeof(u32), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ if (!count) {
+ memset(wa_bb, 0, sizeof(tmp_wa_bb));
+ return len;
+ }
+
+ for (class = 0, count = 0; class < XE_ENGINE_CLASS_MAX; ++class) {
+ tmp_wa_bb[class].cs = tmp + count;
+ count += tmp_wa_bb[class].len;
+ tmp_wa_bb[class].len = 0;
+ }
+
+ /* 3. Parse wa_bb lines again, this time saving the values */
+ count = parse_wa_bb_lines(page, tmp_wa_bb);
+ if (count < 0)
+ return count;
+
+ memcpy(wa_bb, tmp_wa_bb, sizeof(tmp_wa_bb));
+
+ return len;
+}
+
+static ssize_t ctx_restore_post_bb_store(struct config_item *item,
+ const char *data, size_t sz)
+{
+ struct xe_config_group_device *dev = to_xe_config_group_device(item);
+
+ return wa_bb_store(dev->config.ctx_restore_post_bb, dev, data, sz);
+}
+
+CONFIGFS_ATTR(, ctx_restore_post_bb);
CONFIGFS_ATTR(, enable_psmi);
CONFIGFS_ATTR(, engines_allowed);
CONFIGFS_ATTR(, survivability_mode);
static struct configfs_attribute *xe_config_device_attrs[] = {
+ &attr_ctx_restore_post_bb,
&attr_enable_psmi,
&attr_engines_allowed,
&attr_survivability_mode,
struct xe_config_group_device *dev = to_xe_config_group_device(item);
mutex_destroy(&dev->lock);
+
+ kfree(dev->config.ctx_restore_post_bb[0].cs);
kfree(dev);
}
/**
* xe_configfs_get_ctx_restore_post_bb - get configfs ctx_restore_post_bb setting
* @pdev: pci device
+ * @class: hw engine class
+ * @cs: pointer to the bb to use - only valid during probe
*
- * Return: post_ctx_restore setting in configfs
+ * Return: Number of dwords used in the post_ctx_restore setting in configfs
*/
u32 xe_configfs_get_ctx_restore_post_bb(struct pci_dev *pdev,
enum xe_engine_class class,
const u32 **cs)
{
- return 0;
+ struct xe_config_group_device *dev = find_xe_config_group_device(pdev);
+ u32 len;
+
+ if (!dev)
+ return 0;
+
+ *cs = dev->config.ctx_restore_post_bb[class].cs;
+ len = dev->config.ctx_restore_post_bb[class].len;
+ config_group_put(&dev->group);
+
+ return len;
}
int __init xe_configfs_init(void)
projects / thirdparty / kernel / stable.git / commitdiff
