aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/dsa/sja1105/sja1105_dynamic_config.c
diff options
context:
space:
mode:
authorVladimir Oltean <olteanv@gmail.com>2019-06-26 02:39:40 +0300
committerDavid S. Miller <davem@davemloft.net>2019-06-27 11:03:21 -0700
commit17ae6555406a345c7d4096c4c274447e869e9384 (patch)
treef681f424b1411d58d7b86a837b05edc0b9ea65d3 /drivers/net/dsa/sja1105/sja1105_dynamic_config.c
parentnet: dsa: sja1105: Add a high-level overview of the dynamic config interface (diff)
downloadlinux-dev-17ae6555406a345c7d4096c4c274447e869e9384.tar.xz
linux-dev-17ae6555406a345c7d4096c4c274447e869e9384.zip
net: dsa: sja1105: Populate is_static for FDB entries on P/Q/R/S
The reason why this wasn't tackled earlier is that I had hoped I understood the user manual wrong. But unfortunately hacks are required in order to retrieve the static/dynamic nature of FDB entries on SJA1105 P/Q/R/S, since this info is stored in the writeback buffer of the dynamic config command. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/dsa/sja1105/sja1105_dynamic_config.c')
-rw-r--r--drivers/net/dsa/sja1105/sja1105_dynamic_config.c62
1 files changed, 59 insertions, 3 deletions
diff --git a/drivers/net/dsa/sja1105/sja1105_dynamic_config.c b/drivers/net/dsa/sja1105/sja1105_dynamic_config.c
index 3acd48615981..6bfb1696a6f2 100644
--- a/drivers/net/dsa/sja1105/sja1105_dynamic_config.c
+++ b/drivers/net/dsa/sja1105/sja1105_dynamic_config.c
@@ -149,13 +149,11 @@ sja1105pqrs_l2_lookup_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
{
u8 *p = buf + SJA1105PQRS_SIZE_L2_LOOKUP_ENTRY;
const int size = SJA1105_SIZE_DYN_CMD;
- u64 lockeds = 0;
u64 hostcmd;
sja1105_packing(p, &cmd->valid, 31, 31, size, op);
sja1105_packing(p, &cmd->rdwrset, 30, 30, size, op);
sja1105_packing(p, &cmd->errors, 29, 29, size, op);
- sja1105_packing(p, &lockeds, 28, 28, size, op);
sja1105_packing(p, &cmd->valident, 27, 27, size, op);
/* VALIDENT is supposed to indicate "keep or not", but in SJA1105 E/T,
@@ -205,6 +203,64 @@ sja1105pqrs_l2_lookup_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
SJA1105PQRS_SIZE_L2_LOOKUP_ENTRY, op);
}
+/* The switch is so retarded that it makes our command/entry abstraction
+ * crumble apart.
+ *
+ * On P/Q/R/S, the switch tries to say whether a FDB entry
+ * is statically programmed or dynamically learned via a flag called LOCKEDS.
+ * The hardware manual says about this fiels:
+ *
+ * On write will specify the format of ENTRY.
+ * On read the flag will be found cleared at times the VALID flag is found
+ * set. The flag will also be found cleared in response to a read having the
+ * MGMTROUTE flag set. In response to a read with the MGMTROUTE flag
+ * cleared, the flag be set if the most recent access operated on an entry
+ * that was either loaded by configuration or through dynamic reconfiguration
+ * (as opposed to automatically learned entries).
+ *
+ * The trouble with this flag is that it's part of the *command* to access the
+ * dynamic interface, and not part of the *entry* retrieved from it.
+ * Otherwise said, for a sja1105_dynamic_config_read, LOCKEDS is supposed to be
+ * an output from the switch into the command buffer, and for a
+ * sja1105_dynamic_config_write, the switch treats LOCKEDS as an input
+ * (hence we can write either static, or automatically learned entries, from
+ * the core).
+ * But the manual contradicts itself in the last phrase where it says that on
+ * read, LOCKEDS will be set to 1 for all FDB entries written through the
+ * dynamic interface (therefore, the value of LOCKEDS from the
+ * sja1105_dynamic_config_write is not really used for anything, it'll store a
+ * 1 anyway).
+ * This means you can't really write a FDB entry with LOCKEDS=0 (automatically
+ * learned) into the switch, which kind of makes sense.
+ * As for reading through the dynamic interface, it doesn't make too much sense
+ * to put LOCKEDS into the command, since the switch will inevitably have to
+ * ignore it (otherwise a command would be like "read the FDB entry 123, but
+ * only if it's dynamically learned" <- well how am I supposed to know?) and
+ * just use it as an output buffer for its findings. But guess what... that's
+ * what the entry buffer is for!
+ * Unfortunately, what really breaks this abstraction is the fact that it
+ * wasn't designed having the fact in mind that the switch can output
+ * entry-related data as writeback through the command buffer.
+ * However, whether a FDB entry is statically or dynamically learned *is* part
+ * of the entry and not the command data, no matter what the switch thinks.
+ * In order to do that, we'll need to wrap around the
+ * sja1105pqrs_l2_lookup_entry_packing from sja1105_static_config.c, and take
+ * a peek outside of the caller-supplied @buf (the entry buffer), to reach the
+ * command buffer.
+ */
+static size_t
+sja1105pqrs_dyn_l2_lookup_entry_packing(void *buf, void *entry_ptr,
+ enum packing_op op)
+{
+ struct sja1105_l2_lookup_entry *entry = entry_ptr;
+ u8 *cmd = buf + SJA1105PQRS_SIZE_L2_LOOKUP_ENTRY;
+ const int size = SJA1105_SIZE_DYN_CMD;
+
+ sja1105_packing(cmd, &entry->lockeds, 28, 28, size, op);
+
+ return sja1105pqrs_l2_lookup_entry_packing(buf, entry_ptr, op);
+}
+
static void
sja1105et_l2_lookup_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
enum packing_op op)
@@ -485,7 +541,7 @@ struct sja1105_dynamic_table_ops sja1105et_dyn_ops[BLK_IDX_MAX_DYN] = {
/* SJA1105P/Q/R/S: Second generation */
struct sja1105_dynamic_table_ops sja1105pqrs_dyn_ops[BLK_IDX_MAX_DYN] = {
[BLK_IDX_L2_LOOKUP] = {
- .entry_packing = sja1105pqrs_l2_lookup_entry_packing,
+ .entry_packing = sja1105pqrs_dyn_l2_lookup_entry_packing,
.cmd_packing = sja1105pqrs_l2_lookup_cmd_packing,
.access = (OP_READ | OP_WRITE | OP_DEL | OP_SEARCH),
.max_entry_count = SJA1105_MAX_L2_LOOKUP_COUNT,