2021-04-09 16:23:59

by Kunihiko Hayashi

[permalink] [raw]
Subject: [PATCH v10 3/3] PCI: uniphier: Add misc interrupt handler to invoke PME and AER

This patch adds misc interrupt handler to detect and invoke PME/AER event.

In UniPhier PCIe controller, PME/AER signals are assigned to the same
signal as MSI by the internal logic. These signals should be detected by
the internal register, however, DWC MSI handler can't handle these signals.

DWC MSI handler calls .msi_host_isr() callback function, that detects
PME/AER signals using the internal register and invokes the interrupt
with PME/AER vIRQ numbers.

These vIRQ numbers is obtained by uniphier_pcie_port_get_irq() function,
that finds the device that matches PME/AER from the devices associated
with Root Port, and returns its vIRQ number.

Cc: Marc Zyngier <[email protected]>
Cc: Jingoo Han <[email protected]>
Cc: Gustavo Pimentel <[email protected]>
Cc: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Kunihiko Hayashi <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
---
drivers/pci/controller/dwc/pcie-uniphier.c | 101 +++++++++++++++++++++++++----
1 file changed, 89 insertions(+), 12 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-uniphier.c b/drivers/pci/controller/dwc/pcie-uniphier.c
index 7e8bad3..bc4db6f 100644
--- a/drivers/pci/controller/dwc/pcie-uniphier.c
+++ b/drivers/pci/controller/dwc/pcie-uniphier.c
@@ -21,6 +21,7 @@
#include <linux/reset.h>

#include "pcie-designware.h"
+#include "../../pcie/portdrv.h"

#define PCL_PINCTRL0 0x002c
#define PCL_PERST_PLDN_REGEN BIT(12)
@@ -44,7 +45,9 @@
#define PCL_SYS_AUX_PWR_DET BIT(8)

#define PCL_RCV_INT 0x8108
+#define PCL_RCV_INT_ALL_INT_MASK GENMASK(28, 25)
#define PCL_RCV_INT_ALL_ENABLE GENMASK(20, 17)
+#define PCL_RCV_INT_ALL_MSI_MASK GENMASK(12, 9)
#define PCL_CFG_BW_MGT_STATUS BIT(4)
#define PCL_CFG_LINK_AUTO_BW_STATUS BIT(3)
#define PCL_CFG_AER_RC_ERR_MSI_STATUS BIT(2)
@@ -68,6 +71,8 @@ struct uniphier_pcie_priv {
struct reset_control *rst;
struct phy *phy;
struct irq_domain *legacy_irq_domain;
+ int aer_irq;
+ int pme_irq;
};

#define to_uniphier_pcie(x) dev_get_drvdata((x)->dev)
@@ -164,7 +169,15 @@ static void uniphier_pcie_stop_link(struct dw_pcie *pci)

static void uniphier_pcie_irq_enable(struct uniphier_pcie_priv *priv)
{
- writel(PCL_RCV_INT_ALL_ENABLE, priv->base + PCL_RCV_INT);
+ u32 val;
+
+ val = PCL_RCV_INT_ALL_ENABLE;
+ if (pci_msi_enabled())
+ val |= PCL_RCV_INT_ALL_INT_MASK;
+ else
+ val |= PCL_RCV_INT_ALL_MSI_MASK;
+
+ writel(val, priv->base + PCL_RCV_INT);
writel(PCL_RCV_INTX_ALL_ENABLE, priv->base + PCL_RCV_INTX);
}

@@ -228,28 +241,51 @@ static const struct irq_domain_ops uniphier_intx_domain_ops = {
.map = uniphier_pcie_intx_map,
};

-static void uniphier_pcie_irq_handler(struct irq_desc *desc)
+static void uniphier_pcie_misc_isr(struct pcie_port *pp, bool is_msi)
{
- struct pcie_port *pp = irq_desc_get_handler_data(desc);
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci);
- struct irq_chip *chip = irq_desc_get_chip(desc);
- unsigned long reg;
- u32 val, bit, virq;
+ u32 val;

- /* INT for debug */
val = readl(priv->base + PCL_RCV_INT);

if (val & PCL_CFG_BW_MGT_STATUS)
dev_dbg(pci->dev, "Link Bandwidth Management Event\n");
if (val & PCL_CFG_LINK_AUTO_BW_STATUS)
dev_dbg(pci->dev, "Link Autonomous Bandwidth Event\n");
- if (val & PCL_CFG_AER_RC_ERR_MSI_STATUS)
- dev_dbg(pci->dev, "Root Error\n");
- if (val & PCL_CFG_PME_MSI_STATUS)
- dev_dbg(pci->dev, "PME Interrupt\n");
+
+ if (is_msi) {
+ if (val & PCL_CFG_AER_RC_ERR_MSI_STATUS) {
+ dev_dbg(pci->dev, "Root Error Status\n");
+ if (priv->aer_irq)
+ generic_handle_irq(priv->aer_irq);
+ }
+
+ if (val & PCL_CFG_PME_MSI_STATUS) {
+ dev_dbg(pci->dev, "PME Interrupt\n");
+ if (priv->pme_irq)
+ generic_handle_irq(priv->pme_irq);
+ }
+ }

writel(val, priv->base + PCL_RCV_INT);
+}
+
+static void uniphier_pcie_msi_host_isr(struct pcie_port *pp)
+{
+ uniphier_pcie_misc_isr(pp, true);
+}
+
+static void uniphier_pcie_irq_handler(struct irq_desc *desc)
+{
+ struct pcie_port *pp = irq_desc_get_handler_data(desc);
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ unsigned long reg;
+ u32 val, bit, virq;
+
+ uniphier_pcie_misc_isr(pp, false);

/* INTx */
chained_irq_enter(chip, desc);
@@ -317,8 +353,45 @@ static int uniphier_pcie_host_init(struct pcie_port *pp)
return 0;
}

+static int uniphier_pcie_port_get_irq(struct pcie_port *pp, u32 service)
+{
+ struct pci_dev *pcidev;
+ int irq = 0;
+
+ if (!IS_ENABLED(CONFIG_PCIEAER) && !IS_ENABLED(CONFIG_PCIE_PME))
+ return 0;
+
+ /*
+ * Finds the device that matches 'service' from the devices
+ * associated with Root Port, and returns its vIRQ number.
+ */
+ list_for_each_entry(pcidev, &pp->bridge->bus->devices, bus_list) {
+ irq = pcie_port_service_get_irq(pcidev, service);
+ if (irq)
+ break;
+ }
+
+ return irq;
+}
+
+static int uniphier_pcie_host_init_complete(struct pcie_port *pp)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci);
+
+ if (IS_ENABLED(CONFIG_PCIE_PME))
+ priv->pme_irq =
+ uniphier_pcie_port_get_irq(pp, PCIE_PORT_SERVICE_PME);
+ if (IS_ENABLED(CONFIG_PCIEAER))
+ priv->aer_irq =
+ uniphier_pcie_port_get_irq(pp, PCIE_PORT_SERVICE_AER);
+
+ return 0;
+}
+
static const struct dw_pcie_host_ops uniphier_pcie_host_ops = {
.host_init = uniphier_pcie_host_init,
+ .msi_host_isr = uniphier_pcie_msi_host_isr,
};

static int uniphier_pcie_host_enable(struct uniphier_pcie_priv *priv)
@@ -398,7 +471,11 @@ static int uniphier_pcie_probe(struct platform_device *pdev)

priv->pci.pp.ops = &uniphier_pcie_host_ops;

- return dw_pcie_host_init(&priv->pci.pp);
+ ret = dw_pcie_host_init(&priv->pci.pp);
+ if (ret)
+ return ret;
+
+ return uniphier_pcie_host_init_complete(&priv->pci.pp);
}

static const struct of_device_id uniphier_pcie_match[] = {
--
2.7.4


2021-04-15 00:46:33

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH v10 3/3] PCI: uniphier: Add misc interrupt handler to invoke PME and AER

On Sat, Apr 10, 2021 at 01:22:18AM +0900, Kunihiko Hayashi wrote:
> This patch adds misc interrupt handler to detect and invoke PME/AER event.
>
> In UniPhier PCIe controller, PME/AER signals are assigned to the same
> signal as MSI by the internal logic. These signals should be detected by
> the internal register, however, DWC MSI handler can't handle these signals.
>
> DWC MSI handler calls .msi_host_isr() callback function, that detects
> PME/AER signals using the internal register and invokes the interrupt
> with PME/AER vIRQ numbers.
>
> These vIRQ numbers is obtained by uniphier_pcie_port_get_irq() function,
> that finds the device that matches PME/AER from the devices associated
> with Root Port, and returns its vIRQ number.

Why do you use the term "vIRQ"? What exactly is a vIRQ? It seems no
different than the simple "irq" as stored in pci_dev.irq or
pcie_device.irq and passed to generic_handle_irq(). "virq" is also
used in the patch, so if you change one, please change the other as
well.

Bjorn

2021-04-22 16:16:09

by Kunihiko Hayashi

[permalink] [raw]
Subject: Re: [PATCH v10 3/3] PCI: uniphier: Add misc interrupt handler to invoke PME and AER

Hi Bjorn,

On 2021/04/15 4:46, Bjorn Helgaas wrote:
> On Sat, Apr 10, 2021 at 01:22:18AM +0900, Kunihiko Hayashi wrote:
>> This patch adds misc interrupt handler to detect and invoke PME/AER event.
>>
>> In UniPhier PCIe controller, PME/AER signals are assigned to the same
>> signal as MSI by the internal logic. These signals should be detected by
>> the internal register, however, DWC MSI handler can't handle these signals.
>>
>> DWC MSI handler calls .msi_host_isr() callback function, that detects
>> PME/AER signals using the internal register and invokes the interrupt
>> with PME/AER vIRQ numbers.
>>
>> These vIRQ numbers is obtained by uniphier_pcie_port_get_irq() function,
>> that finds the device that matches PME/AER from the devices associated
>> with Root Port, and returns its vIRQ number.
>
> Why do you use the term "vIRQ"? What exactly is a vIRQ? It seems no
> different than the simple "irq" as stored in pci_dev.irq or
> pcie_device.irq and passed to generic_handle_irq(). "virq" is also
> used in the patch, so if you change one, please change the other as
> well.
Indeed, I used "virq" in contrast to "hwirq", but that seems wrong.
This interrupt number is equivarent to pci_dev.irq, so I'll fix it.

Thank you,

---
Best Regards
Kunihiko Hayashi