Merge tag 'scmi-fixes-5.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/fixes

Arm SCMI firmware driver fixes for v5.19

Few more fixes to address:
1. Issue reported on Juno with HDLCD clock which turned out to be yet
another firmware issue. The firmware is not conformant to the spec and
we now have to workaround as this may be copied to other platforms as
well. The spec expects to return size of 3 for a range clock rate
description while the firmware returns 1. We have other ways to validate
all the 3 entries the driver reads are polpulated and we use the same
to workaround this firmware bug.

2. Optee transport not setting the correct reponse length which is similar
to the one reported earlier on Rockchip platform.

3. Drop the usage of the deprecated ida_simple_{get,remove} and migrate to the
ida_{alloc,free}

* tag 'scmi-fixes-5.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
firmware: arm_scmi: Remove usage of the deprecated ida_simple_xxx API
firmware: arm_scmi: Fix response size warning for OPTEE transport
firmware: arm_scmi: Relax CLOCK_DESCRIBE_RATES out-of-spec checks

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Arnd Bergmann <[e-mail]>

drivers/firmware/arm_scmi/bus.c

···
 		return NULL;
 	}
 
-	id = ida_simple_get(&scmi_bus_id, 1, 0, GFP_KERNEL);
+	id = ida_alloc_min(&scmi_bus_id, 1, GFP_KERNEL);
 	if (id < 0) {
 		kfree_const(scmi_dev->name);
 		kfree(scmi_dev);
···
 put_dev:
 	kfree_const(scmi_dev->name);
 	put_device(&scmi_dev->dev);
-	ida_simple_remove(&scmi_bus_id, id);
+	ida_free(&scmi_bus_id, id);
 	return NULL;
 }
 
···
 {
 	kfree_const(scmi_dev->name);
 	scmi_handle_put(scmi_dev->handle);
-	ida_simple_remove(&scmi_bus_id, scmi_dev->id);
+	ida_free(&scmi_bus_id, scmi_dev->id);
 	device_unregister(&scmi_dev->dev);
 }
 

drivers/firmware/arm_scmi/clock.c

···
 }
 
 struct scmi_clk_ipriv {
+	struct device *dev;
 	u32 clk_id;
 	struct scmi_clock_info *clk;
 };
···
 	st->num_remaining = NUM_REMAINING(flags);
 	st->num_returned = NUM_RETURNED(flags);
 	p->clk->rate_discrete = RATE_DISCRETE(flags);
+
+	/* Warn about out of spec replies ... */
+	if (!p->clk->rate_discrete &&
+	    (st->num_returned != 3 || st->num_remaining != 0)) {
+		dev_warn(p->dev,
+			 "Out-of-spec CLOCK_DESCRIBE_RATES reply for %s - returned:%d remaining:%d rx_len:%zd\n",
+			 p->clk->name, st->num_returned, st->num_remaining,
+			 st->rx_len);
+
+		/*
+		 * A known quirk: a triplet is returned but num_returned != 3
+		 * Check for a safe payload size and fix.
+		 */
+		if (st->num_returned != 3 && st->num_remaining == 0 &&
+		    st->rx_len == sizeof(*r) + sizeof(__le32) * 2 * 3) {
+			st->num_returned = 3;
+			st->num_remaining = 0;
+		} else {
+			dev_err(p->dev,
+				"Cannot fix out-of-spec reply !\n");
+			return -EPROTO;
+		}
+	}
 
 	return 0;
 }
···
 
 		*rate = RATE_TO_U64(r->rate[st->loop_idx]);
 		p->clk->list.num_rates++;
-		//XXX dev_dbg(ph->dev, "Rate %llu Hz\n", *rate);
 	}
 
 	return ret;
···
 	struct scmi_clk_ipriv cpriv = {
 		.clk_id = clk_id,
 		.clk = clk,
+		.dev = ph->dev,
 	};
 
 	iter = ph->hops->iter_response_init(ph, &ops, SCMI_MAX_NUM_RATES,

drivers/firmware/arm_scmi/driver.c

···
 		if (ret)
 			break;
 
+		st->rx_len = i->t->rx.len;
 		ret = iops->update_state(st, i->resp, i->priv);
 		if (ret)
 			break;

drivers/firmware/arm_scmi/optee.c

···
 	u32 channel_id;
 	u32 tee_session;
 	u32 caps;
+	u32 rx_len;
 	struct mutex mu;
 	struct scmi_chan_info *cinfo;
 	union {
···
 		return -EIO;
 	}
 
+	/* Save response size */
+	channel->rx_len = param[2].u.memref.size;
+
 	return 0;
 }
 
···
 	shbuf = tee_shm_get_va(channel->tee_shm, 0);
 	memset(shbuf, 0, msg_size);
 	channel->req.msg = shbuf;
+	channel->rx_len = msg_size;
 
 	return 0;
 }
···
 	struct scmi_optee_channel *channel = cinfo->transport_info;
 
 	if (channel->tee_shm)
-		msg_fetch_response(channel->req.msg, SCMI_OPTEE_MAX_MSG_SIZE, xfer);
+		msg_fetch_response(channel->req.msg, channel->rx_len, xfer);
 	else
 		shmem_fetch_response(channel->req.shmem, xfer);
 }

drivers/firmware/arm_scmi/protocols.h

···
  * @max_resources: Maximum acceptable number of items, configured by the caller
  *		   depending on the underlying resources that it is querying.
  * @loop_idx: The iterator loop index in the current multi-part reply.
+ * @rx_len: Size in bytes of the currenly processed message; it can be used by
+ *	    the user of the iterator to verify a reply size.
  * @priv: Optional pointer to some additional state-related private data setup
  *	  by the caller during the iterations.
  */
···
 	unsigned int num_remaining;
 	unsigned int max_resources;
 	unsigned int loop_idx;
+	size_t rx_len;
 	void *priv;
 };