Re: [PATCH 2/2] firmware: arm_scmi: Add qcom hvc/shmem transport

On 7/18/2023 11:42 AM, Krzysztof Kozlowski wrote:

On 18/07/2023 20:25, Nikunj Kela wrote:

quoted

quoted

quoted

+
+	scmi_info = devm_kzalloc(dev, sizeof(*scmi_info), GFP_KERNEL);
+	if (!scmi_info)
+		return -ENOMEM;
+
+	np = of_parse_phandle(cdev->of_node, "shmem", 0);
+	if (!of_device_is_compatible(np, "arm,scmi-shmem"))

You leak here reference.

Wouldn't the devm_* API take care of that implicitly? It is same in
smc.c as well.

Thanks for bringing my attention to this. I sent a fix for smc.c. Fix
your patch as well, please.

Thanks, I thought you were referring to kzalloc cleanup. Will include 
this fix. BTW, you may need to fix mailbox.c as well.

quoted

quoted

quoted

+		return -ENXIO;
+
+	ret = of_address_to_resource(np, 0, &res);
+	of_node_put(np);
+	if (ret) {
+		dev_err(cdev, "failed to get SCMI Tx shared memory\n");
+		return ret;
+	}
+
+	size = resource_size(&res);
+
+	/* let's map 2 additional ulong since
+	 * func-id & capability-id are kept after shmem.
+	 *     +-------+
+	 *     |       |
+	 *     | shmem |
+	 *     |       |
+	 *     |       |
+	 *     +-------+ <-- size
+	 *     | funcId|
+	 *     +-------+ <-- size + sizeof(ulong)
+	 *     | capId |
+	 *     +-------+ <-- size + 2*sizeof(ulong)
+	 */
+
+	scmi_info->shmem = devm_ioremap(dev, res.start,
+					size + 2 * sizeof(unsigned long));
+	if (!scmi_info->shmem) {
+		dev_err(dev, "failed to ioremap SCMI Tx shared memory\n");
+		return -EADDRNOTAVAIL;
+	}
+
+	func_id = readl((void *)(scmi_info->shmem) + size);
+
+#ifdef CONFIG_ARM64
+	cap_id = readq((void *)(scmi_info->shmem) + size +
+		       sizeof(unsigned long));
+#else
+	cap_id = readl((void *)(scmi_info->shmem) + size +
+		       sizeof(unsigned long));
+#endif
+
+	/*
+	 * If there is an interrupt named "a2p", then the service and
+	 * completion of a message is signaled by an interrupt rather than by
+	 * the return of the hvc call.
+	 */
+	irq = of_irq_get_byname(cdev->of_node, "a2p");
+	if (irq > 0) {
+		ret = devm_request_irq(dev, irq, qcom_hvc_msg_done_isr,
+				       IRQF_NO_SUSPEND,
+				       dev_name(dev), scmi_info);
+		if (ret) {
+			dev_err(dev, "failed to setup SCMI completion irq\n");

return dev_err_probe, unless this is not called in probe... but then
using devm-interface raises questions.

This is copied as is from existing smc.c

I understand and I hope you understand the code you copied. If there is
a bug in existing code, please do not copy it to new code (like leaking
OF node reference).

Best regards,
Krzysztof

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel