[PATCH v3 1/2] soc: qcom: smp2p: Add irqchip state support

[Deepak Kumar Singh <deepak.singh@oss.qualcomm.com>]

From: Chris Lew <chris.lew@oss.qualcomm.com>

A remoteproc booted during earlier boot stages such as UEFI or the
bootloader, may need to be attached to without restarting the remoteproc
hardware. To do this the remoteproc will need to check the ready and
handover states in smp2p without an interrupt notification. Create
qcom_smp2p_start_in() to initialize the shadow state without notifying
clients because these early events happened in the past.

Add support for the .irq_get_irqchip_state callback so remoteproc can
read the current state of the fatal, ready and handover bits.

Signed-off-by: Chris Lew <chris.lew@oss.qualcomm.com>
Signed-off-by: Deepak Kumar Singh <deepak.singh@oss.qualcomm.com>
---
 drivers/soc/qcom/smp2p.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/drivers/soc/qcom/smp2p.c b/drivers/soc/qcom/smp2p.c
index cb515c2340c1..c27ffb44b825 100644
--- a/drivers/soc/qcom/smp2p.c
+++ b/drivers/soc/qcom/smp2p.c
@@ -222,6 +222,39 @@ static void qcom_smp2p_negotiate(struct qcom_smp2p *smp2p)
 	}
 }
 
+static void qcom_smp2p_start_in(struct qcom_smp2p *smp2p)
+{
+	unsigned int smem_id = smp2p->smem_items[SMP2P_INBOUND];
+	unsigned int pid = smp2p->remote_pid;
+	char buf[SMP2P_MAX_ENTRY_NAME];
+	struct smp2p_smem_item *in;
+	struct smp2p_entry *entry;
+	size_t size;
+	int i;
+
+	in = qcom_smem_get(pid, smem_id, &size);
+	if (IS_ERR(in))
+		return;
+
+	smp2p->in = in;
+
+	/* Check if version is initialized by the remote. */
+	if (in->version == 0)
+		return;
+
+	for (i = smp2p->valid_entries; i < in->valid_entries; i++) {
+		list_for_each_entry(entry, &smp2p->inbound, node) {
+			memcpy(buf, in->entries[i].name, sizeof(buf));
+			if (!strcmp(buf, entry->name)) {
+				entry->value = &in->entries[i].value;
+				entry->last_value = readl(entry->value);
+				break;
+			}
+		}
+	}
+	smp2p->valid_entries = i;
+}
+
 static void qcom_smp2p_notify_in(struct qcom_smp2p *smp2p)
 {
 	struct smp2p_smem_item *in;
@@ -368,12 +401,31 @@ static void smp2p_irq_print_chip(struct irq_data *irqd, struct seq_file *p)
 	seq_printf(p, "%8s", dev_name(entry->smp2p->dev));
 }
 
+static int smp2p_irq_get_irqchip_state(struct irq_data *irqd, enum irqchip_irq_state which,
+				       bool *state)
+{
+	struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
+	u32 val;
+
+	if (which != IRQCHIP_STATE_LINE_LEVEL)
+		return -EINVAL;
+
+	if (!entry->value)
+		return -ENODEV;
+
+	val = readl(entry->value);
+	*state = !!(val & BIT(irqd_to_hwirq(irqd)));
+
+	return 0;
+}
+
 static struct irq_chip smp2p_irq_chip = {
 	.name           = "smp2p",
 	.irq_mask       = smp2p_mask_irq,
 	.irq_unmask     = smp2p_unmask_irq,
 	.irq_set_type	= smp2p_set_irq_type,
 	.irq_print_chip = smp2p_irq_print_chip,
+	.irq_get_irqchip_state = smp2p_irq_get_irqchip_state,
 };
 
 static int smp2p_irq_map(struct irq_domain *d,
@@ -618,6 +670,9 @@ static int qcom_smp2p_probe(struct platform_device *pdev)
 		}
 	}
 
+	/* Check inbound entries in the case of early boot processor */
+	qcom_smp2p_start_in(smp2p);
+
 	/* Kick the outgoing edge after allocating entries */
 	qcom_smp2p_kick(smp2p);
 

-- 
2.34.1