[PATCH v4 24/40] fsi: aspeed: Add interrupt support

Eddie James
2024-06-05T21:23:40Z

Handle slave interrupts and pass them to the FSI core.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
drivers/fsi/fsi-master-aspeed.c | 106 ++++++++++++++++++++++-
include/trace/events/fsi_master_aspeed.h | 12 +++
2 files changed, 115 insertions(+), 3 deletions(-)

diff --git a/drivers/fsi/fsi-master-aspeed.c b/drivers/fsi/fsi-master-aspeed.c
index eecd64bc29512..34f4c9e00e43d 100644
--- a/drivers/fsi/fsi-master-aspeed.c
+++ b/drivers/fsi/fsi-master-aspeed.c
@@ -6,6 +6,8 @@
#include <linux/delay.h>
#include <linux/fsi.h>
#include <linux/io.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
@@ -25,11 +27,13 @@ struct fsi_master_aspeed_data {
struct fsi_master_aspeed {
struct fsi_master master;
spinlock_t lock; /* protect HW access */
+ struct irq_domain *irq_domain;
struct device *dev;
void __iomem *base;
void __iomem *ctrl;
struct clk *clk;
struct gpio_desc *cfam_reset_gpio;
+ u32 irq_mask;
};

#define to_fsi_master_aspeed(m) \
@@ -79,6 +83,11 @@ static const u32 fsi_base = 0xa0000000;
#define STATUS_TIMEOUT BIT(4)

/* OPB_IRQ_MASK */
+#define FSI_MASTER_ERROR_IRQ BIT(28)
+#define FSI_PORT_ERROR_IRQ BIT(27)
+#define FSI_HOTPLUG_IRQ BIT(26)
+#define FSI_REMOTE_SLV_IRQ(l) (BIT(FSI_REMOTE_SLV_IRQ_BIT) << (l))
+#define FSI_REMOTE_SLV_IRQ_BIT 18
#define OPB1_XFER_ACK_EN BIT(17)
#define OPB0_XFER_ACK_EN BIT(16)

@@ -96,7 +105,7 @@ static const u32 fsi_base = 0xa0000000;
#define OPB_RC_CTRL_OPB BIT(18) /* Access controller over OPB, not AHB (AST27xx+) */
#define OPB_RC_XFER_ACK_EN BIT(16) /* Enable OPBx xfer ack bit without mask */
#define OPB_RC_COUNT GENMASK(15, 0) /* Number of retries */
-#define OPB_RC_DEFAULT 0x10
+#define OPB_RC_DEFAULT (OPB_RC_XFER_ACK_EN | 0x10)

#define CREATE_TRACE_POINTS
#include <trace/events/fsi_master_aspeed.h>
@@ -322,11 +331,76 @@ static int aspeed_master_break(struct fsi_master *master, int link)
return aspeed_master_write(master, link, 0, addr, &cmd, 4);
}

+static int aspeed_master_link_enable(struct fsi_master *master, int link, bool enable)
+{
+ struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
+ unsigned long flags;
+ int rc;
+
+ spin_lock_irqsave(&aspeed->lock, flags);
+ if (enable) {
+ rc = fsi_master_link_enable(master, link, enable);
+ if (rc)
+ goto done;
+
+ aspeed->irq_mask |= FSI_REMOTE_SLV_IRQ(link);
+ writel(aspeed->irq_mask, aspeed->base + OPB_IRQ_MASK);
+ } else {
+ aspeed->irq_mask &= ~FSI_REMOTE_SLV_IRQ(link);
+ writel(aspeed->irq_mask, aspeed->base + OPB_IRQ_MASK);
+
+ rc = fsi_master_link_enable(master, link, enable);
+ }
+
+done:
+ spin_unlock_irqrestore(&aspeed->lock, flags);
+ return rc;
+}
+
+static irqreturn_t aspeed_master_irq(int irq, void *data)
+{
+ struct fsi_master_aspeed *aspeed = data;
+ unsigned long size = FSI_REMOTE_SLV_IRQ_BIT + aspeed->master.n_links;
+ unsigned long bit = FSI_REMOTE_SLV_IRQ_BIT;
+ unsigned long status;
+
+ status = readl(aspeed->base + OPB_IRQ_STATUS);
+ writel(0, aspeed->base + OPB_IRQ_MASK);
+
+ for_each_set_bit_from(bit, &status, size)
+ fsi_master_irq(&aspeed->master, aspeed->irq_domain, bit - FSI_REMOTE_SLV_IRQ_BIT);
+
+ writel(status, aspeed->base + OPB_IRQ_STATUS);
+ writel(0, aspeed->base + OPB_IRQ_STATUS);
+ writel(aspeed->irq_mask, aspeed->base + OPB_IRQ_MASK);
+
+ trace_fsi_master_aspeed_irq(status);
+ return IRQ_HANDLED;
+}
+
+static int aspeed_master_irqd_map(struct irq_domain *domain, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ struct fsi_master_aspeed *aspeed = domain->host_data;
+
+ irq_set_chip_and_handler(irq, &aspeed->master.irq_chip, handle_simple_irq);
+ irq_set_chip_data(irq, &aspeed->master);
+
+ return 0;
+}
+
+static const struct irq_domain_ops aspeed_master_irq_domain_ops = {
+ .map = aspeed_master_irqd_map,
+};
+
static void aspeed_master_release(struct device *dev)
{
struct fsi_master_aspeed *aspeed =
to_fsi_master_aspeed(to_fsi_master(dev));

+ if (aspeed->irq_domain)
+ irq_domain_remove(aspeed->irq_domain);
+
regmap_exit(aspeed->master.map);
kfree(aspeed);
}
@@ -477,6 +551,7 @@ static int fsi_master_aspeed_probe(struct platform_device *pdev)
struct resource *res;
unsigned int reg;
int rc, links;
+ int irq;

rc = tacoma_cabled_fsi_fixup(&pdev->dev);
if (rc) {
@@ -567,11 +642,12 @@ static int fsi_master_aspeed_probe(struct platform_device *pdev)
aspeed->master.dev.of_node = of_node_get(dev_of_node(&pdev->dev));

aspeed->master.n_links = links;
- aspeed->master.flags = FSI_MASTER_FLAG_RELA;
+ aspeed->master.flags = FSI_MASTER_FLAG_INTERRUPT | FSI_MASTER_FLAG_RELA;
aspeed->master.read = aspeed_master_read;
aspeed->master.write = aspeed_master_write;
aspeed->master.send_break = aspeed_master_break;
aspeed->master.term = aspeed_master_term;
+ aspeed->master.link_enable = aspeed_master_link_enable;

dev_set_drvdata(&pdev->dev, aspeed);

@@ -579,9 +655,30 @@ static int fsi_master_aspeed_probe(struct platform_device *pdev)
if (rc)
goto err_regmap;

+ irq = platform_get_irq(pdev, 0);
+ if (irq > 0) {
+ unsigned int size = links * FSI_IRQ_COUNT;
+
+ aspeed->irq_domain = irq_domain_add_linear(aspeed->dev->of_node, size,
+ &aspeed_master_irq_domain_ops, aspeed);
+ if (aspeed->irq_domain) {
+ rc = devm_request_irq(aspeed->dev, irq, aspeed_master_irq, 0,
+ dev_name(aspeed->dev), aspeed);
+ if (rc) {
+ dev_warn(aspeed->dev, "failed to request irq:%d\n", irq);
+ irq_domain_remove(aspeed->irq_domain);
+ aspeed->irq_domain = NULL;
+ } else {
+ dev_info(aspeed->dev, "enabling interrupts irq:%d\n", irq);
+ }
+ } else {
+ dev_warn(aspeed->dev, "failed to create irq domain\n");
+ }
+ }
+
rc = fsi_master_register(&aspeed->master);
if (rc)
- goto err_regmap;
+ goto err_irq;

/* At this point, fsi_master_register performs the device_initialize(),
* and holds the sole reference on master.dev. This means the device
@@ -593,6 +690,9 @@ static int fsi_master_aspeed_probe(struct platform_device *pdev)
get_device(&aspeed->master.dev);
return 0;

+err_irq:
+ if (aspeed->irq_domain)
+ irq_domain_remove(aspeed->irq_domain);
err_regmap:
regmap_exit(aspeed->master.map);
err_release:
diff --git a/include/trace/events/fsi_master_aspeed.h b/include/trace/events/fsi_master_aspeed.h
index 7eeecbfec7f09..dba1776334a0e 100644
--- a/include/trace/events/fsi_master_aspeed.h
+++ b/include/trace/events/fsi_master_aspeed.h
@@ -8,6 +8,18 @@

#include <linux/tracepoint.h>

+TRACE_EVENT(fsi_master_aspeed_irq,
+ TP_PROTO(uint32_t status),
+ TP_ARGS(status),
+ TP_STRUCT__entry(
+ __field(uint32_t, status)
+ ),
+ TP_fast_assign(
+ __entry->status = status;
+ ),
+ TP_printk("status %08x", __entry->status)
+);
+
TRACE_EVENT(fsi_master_aspeed_opb_xfer,
TP_PROTO(uint32_t addr, uint32_t size, uint32_t data, bool read),
TP_ARGS(addr, size, data, read),
--
2.39.3