cregit-Linux how code gets into the kernel

Release 4.14 arch/powerpc/platforms/4xx/hsta_msi.c

/*
 * MSI support for PPC4xx SoCs using High Speed Transfer Assist (HSTA) for
 * generation of the interrupt.
 *
 * Copyright © 2013 Alistair Popple <alistair@popple.id.au> IBM Corporation
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/msi.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/semaphore.h>
#include <asm/msi_bitmap.h>
#include <asm/ppc-pci.h>


struct ppc4xx_hsta_msi {
	
struct device *dev;

	/* The ioremapped HSTA MSI IO space */
	
u32 __iomem *data;

	/* Physical address of HSTA MSI IO space */
	
u64 address;
	
struct msi_bitmap bmp;

	/* An array mapping offsets to hardware IRQs */
	
int *irq_map;

	/* Number of hwirqs supported */
	
int irq_count;
};

static struct ppc4xx_hsta_msi ppc4xx_hsta_msi;


static int hsta_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) { struct msi_msg msg; struct msi_desc *entry; int irq, hwirq; u64 addr; /* We don't support MSI-X */ if (type == PCI_CAP_ID_MSIX) { pr_debug("%s: MSI-X not supported.\n", __func__); return -EINVAL; } for_each_pci_msi_entry(entry, dev) { irq = msi_bitmap_alloc_hwirqs(&ppc4xx_hsta_msi.bmp, 1); if (irq < 0) { pr_debug("%s: Failed to allocate msi interrupt\n", __func__); return irq; } hwirq = ppc4xx_hsta_msi.irq_map[irq]; if (!hwirq) { pr_err("%s: Failed mapping irq %d\n", __func__, irq); return -EINVAL; } /* * HSTA generates interrupts on writes to 128-bit aligned * addresses. */ addr = ppc4xx_hsta_msi.address + irq*0x10; msg.address_hi = upper_32_bits(addr); msg.address_lo = lower_32_bits(addr); /* Data is not used by the HSTA. */ msg.data = 0; pr_debug("%s: Setup irq %d (0x%0llx)\n", __func__, hwirq, (((u64) msg.address_hi) << 32) | msg.address_lo); if (irq_set_msi_desc(hwirq, entry)) { pr_err( "%s: Invalid hwirq %d specified in device tree\n", __func__, hwirq); msi_bitmap_free_hwirqs(&ppc4xx_hsta_msi.bmp, irq, 1); return -EINVAL; } pci_write_msi_msg(hwirq, &msg); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alistair Popple20689.57%120.00%
Alexander Gordeev208.70%120.00%
Jiang Liu31.30%240.00%
Michael Ellerman10.43%120.00%
Total230100.00%5100.00%


static int hsta_find_hwirq_offset(int hwirq) { int irq; /* Find the offset given the hwirq */ for (irq = 0; irq < ppc4xx_hsta_msi.irq_count; irq++) if (ppc4xx_hsta_msi.irq_map[irq] == hwirq) return irq; return -EINVAL; }

Contributors

PersonTokensPropCommitsCommitProp
Alistair Popple46100.00%1100.00%
Total46100.00%1100.00%


static void hsta_teardown_msi_irqs(struct pci_dev *dev) { struct msi_desc *entry; int irq; for_each_pci_msi_entry(entry, dev) { if (!entry->irq) continue; irq = hsta_find_hwirq_offset(entry->irq); /* entry->irq should always be in irq_map */ BUG_ON(irq < 0); irq_set_msi_desc(entry->irq, NULL); msi_bitmap_free_hwirqs(&ppc4xx_hsta_msi.bmp, irq, 1); pr_debug("%s: Teardown IRQ %u (index %u)\n", __func__, entry->irq, irq); } }

Contributors

PersonTokensPropCommitsCommitProp
Alistair Popple8396.51%133.33%
Jiang Liu22.33%133.33%
Michael Ellerman11.16%133.33%
Total86100.00%3100.00%


static int hsta_msi_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct resource *mem; int irq, ret, irq_count; struct pci_controller *phb; mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!mem) { dev_err(dev, "Unable to get mmio space\n"); return -EINVAL; } irq_count = of_irq_count(dev->of_node); if (!irq_count) { dev_err(dev, "Unable to find IRQ range\n"); return -EINVAL; } ppc4xx_hsta_msi.dev = dev; ppc4xx_hsta_msi.address = mem->start; ppc4xx_hsta_msi.data = ioremap(mem->start, resource_size(mem)); ppc4xx_hsta_msi.irq_count = irq_count; if (!ppc4xx_hsta_msi.data) { dev_err(dev, "Unable to map memory\n"); return -ENOMEM; } ret = msi_bitmap_alloc(&ppc4xx_hsta_msi.bmp, irq_count, dev->of_node); if (ret) goto out; ppc4xx_hsta_msi.irq_map = kmalloc(sizeof(int) * irq_count, GFP_KERNEL); if (!ppc4xx_hsta_msi.irq_map) { ret = -ENOMEM; goto out1; } /* Setup a mapping from irq offsets to hardware irq numbers */ for (irq = 0; irq < irq_count; irq++) { ppc4xx_hsta_msi.irq_map[irq] = irq_of_parse_and_map(dev->of_node, irq); if (!ppc4xx_hsta_msi.irq_map[irq]) { dev_err(dev, "Unable to map IRQ\n"); ret = -EINVAL; goto out2; } } list_for_each_entry(phb, &hose_list, list_node) { phb->controller_ops.setup_msi_irqs = hsta_setup_msi_irqs; phb->controller_ops.teardown_msi_irqs = hsta_teardown_msi_irqs; } return 0; out2: kfree(ppc4xx_hsta_msi.irq_map); out1: msi_bitmap_free(&ppc4xx_hsta_msi.bmp); out: iounmap(ppc4xx_hsta_msi.data); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Alistair Popple30092.31%120.00%
Daniel Axtens216.46%120.00%
Wei Yongjun30.92%240.00%
Michael Ellerman10.31%120.00%
Total325100.00%5100.00%

static const struct of_device_id hsta_msi_ids[] = { { .compatible = "ibm,hsta-msi", }, {} }; static struct platform_driver hsta_msi_driver = { .probe = hsta_msi_probe, .driver = { .name = "hsta-msi", .of_match_table = hsta_msi_ids, }, };
static int hsta_msi_init(void) { return platform_driver_register(&hsta_msi_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Alistair Popple15100.00%1100.00%
Total15100.00%1100.00%

subsys_initcall(hsta_msi_init);

Overall Contributors

PersonTokensPropCommitsCommitProp
Alistair Popple76393.28%111.11%
Daniel Axtens242.93%222.22%
Alexander Gordeev202.44%111.11%
Jiang Liu50.61%222.22%
Wei Yongjun30.37%222.22%
Michael Ellerman30.37%111.11%
Total818100.00%9100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.