linux-zen-server/drivers/net/wwan/iosm/iosm_ipc_irq.c

91 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2020-21 Intel Corporation.
*/
#include "iosm_ipc_pcie.h"
#include "iosm_ipc_protocol.h"
static void ipc_write_dbell_reg(struct iosm_pcie *ipc_pcie, int irq_n, u32 data)
{
void __iomem *write_reg;
/* Select the first doorbell register, which is only currently needed
* by CP.
*/
write_reg = (void __iomem *)((u8 __iomem *)ipc_pcie->ipc_regs +
ipc_pcie->doorbell_write +
(irq_n * ipc_pcie->doorbell_reg_offset));
/* Fire the doorbell irq by writing data on the doorbell write pointer
* register.
*/
iowrite32(data, write_reg);
}
void ipc_doorbell_fire(struct iosm_pcie *ipc_pcie, int irq_n, u32 data)
{
ipc_write_dbell_reg(ipc_pcie, irq_n, data);
}
/* Threaded Interrupt handler for MSI interrupts */
static irqreturn_t ipc_msi_interrupt(int irq, void *dev_id)
{
struct iosm_pcie *ipc_pcie = dev_id;
int instance = irq - ipc_pcie->pci->irq;
/* Shift the MSI irq actions to the IPC tasklet. IRQ_NONE means the
* irq was not from the IPC device or could not be served.
*/
if (instance >= ipc_pcie->nvec)
return IRQ_NONE;
if (!test_bit(0, &ipc_pcie->suspend))
ipc_imem_irq_process(ipc_pcie->imem, instance);
return IRQ_HANDLED;
}
void ipc_release_irq(struct iosm_pcie *ipc_pcie)
{
struct pci_dev *pdev = ipc_pcie->pci;
if (pdev->msi_enabled) {
while (--ipc_pcie->nvec >= 0)
free_irq(pdev->irq + ipc_pcie->nvec, ipc_pcie);
}
pci_free_irq_vectors(pdev);
}
int ipc_acquire_irq(struct iosm_pcie *ipc_pcie)
{
struct pci_dev *pdev = ipc_pcie->pci;
int i, rc = -EINVAL;
ipc_pcie->nvec = pci_alloc_irq_vectors(pdev, IPC_MSI_VECTORS,
IPC_MSI_VECTORS, PCI_IRQ_MSI);
if (ipc_pcie->nvec < 0) {
rc = ipc_pcie->nvec;
goto error;
}
if (!pdev->msi_enabled)
goto error;
for (i = 0; i < ipc_pcie->nvec; ++i) {
rc = request_threaded_irq(pdev->irq + i, NULL,
ipc_msi_interrupt, IRQF_ONESHOT,
KBUILD_MODNAME, ipc_pcie);
if (rc) {
dev_err(ipc_pcie->dev, "unable to grab IRQ, rc=%d", rc);
ipc_pcie->nvec = i;
ipc_release_irq(ipc_pcie);
goto error;
}
}
error:
return rc;
}