[PATCH v2] PPC4xx: Adding PCI(E) MSI support
Josh Boyer
jwboyer at linux.vnet.ibm.com
Tue Nov 30 05:35:35 EST 2010
On Mon, Nov 15, 2010 at 12:15:06PM -0800, tmarri at apm.com wrote:
>From: Tirumala Marri <tmarri at apm.com>
>
>This patch adds MSI support for 440SPe, 460Ex, 460Sx and 405Ex.
>
My apologies in the delay here. I was on holiday for a while and never
got back to review this. A few notes below.
Also, I've added a few patches from Victor for suspend/idle support in
my next branch that cause a minor conflict with this one. It's not a
big deal to fix, but if you rework the patch for the comments, rebasing
it to my next branch would be appreciated.
>diff --git a/arch/powerpc/sysdev/ppc4xx_msi.c b/arch/powerpc/sysdev/ppc4xx_msi.c
>new file mode 100644
>index 0000000..9ed559f
>--- /dev/null
>+++ b/arch/powerpc/sysdev/ppc4xx_msi.c
>@@ -0,0 +1,311 @@
>+/*
>+ * Adding PCI-E MSI support for PPC4XX SoCs.
>+ *
>+ * Copyright (c) 2010, Applied Micro Circuits Corporation
>+ * Authors: Tirumala R Marri <tmarri at apm.com>
>+ * Feng Kan <fkan at apm.com>
>+ *
>+ * 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.
>+ *
>+ * This program is distributed in the hope that it will be useful,
>+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
>+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>+ * GNU General Public License for more details.
>+ *
>+ * You should have received a copy of the GNU General Public License
>+ * along with this program; if not, write to the Free Software
>+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
>+ * MA 02111-1307 USA
>+ */
>+
>+#include <linux/irq.h>
>+#include <linux/bootmem.h>
>+#include <linux/pci.h>
>+#include <linux/msi.h>
>+#include <linux/of_platform.h>
>+#include <linux/interrupt.h>
>+#include <asm/prom.h>
>+#include <asm/hw_irq.h>
>+#include <asm/ppc-pci.h>
>+#include <boot/dcr.h>
This still seems weird to include. Perhaps you should duplicate the
macros you need into asm/dcr-regs.h or something.
>+#include <asm/dcr-regs.h>
>+#include <asm/msi_bitmap.h>
>+
>+#define PEIH_TERMADH 0x00
>+#define PEIH_TERMADL 0x08
>+#define PEIH_MSIED 0x10
>+#define PEIH_MSIMK 0x18
>+#define PEIH_MSIASS 0x20
>+#define PEIH_FLUSH0 0x30
>+#define PEIH_FLUSH1 0x38
>+#define PEIH_CNTRST 0x48
>+#define NR_MSI_IRQS 4
>+
>+LIST_HEAD(msi_head);
>+struct ppc4xx_msi {
>+ u32 msi_addr_lo;
>+ u32 msi_addr_hi;
>+ void __iomem *msi_regs;
>+ int msi_virqs[NR_MSI_IRQS];
>+ struct msi_bitmap bitmap;
>+ struct list_head list;
>+};
>+
>+struct ppc4xx_msi_feature {
>+ u32 ppc4xx_pic_ip;
>+ u32 msiir_offset;
>+};
>+
>+static int ppc4xx_msi_init_allocator(struct platform_device *dev,
>+ struct ppc4xx_msi *msi_data)
>+{
>+ int err;
>+
>+ err = msi_bitmap_alloc(&msi_data->bitmap, NR_MSI_IRQS,
>+ dev->dev.of_node);
>+ if (err)
>+ return err;
>+
>+ err = msi_bitmap_reserve_dt_hwirqs(&msi_data->bitmap);
>+ if (err < 0) {
>+ msi_bitmap_free(&msi_data->bitmap);
>+ return err;
>+ }
>+
>+ return 0;
>+}
>+
>+static int ppc4xx_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
>+{
>+ int err = 0;
>+ int int_no = -ENOMEM;
>+ unsigned int virq;
>+ struct msi_msg msg;
>+ struct msi_desc *entry;
>+ struct device_node *msi_dev = NULL;
>+ struct ppc4xx_msi *msi_data = dev->dev.platform_data;
>+
>+ msi_dev = of_find_node_by_name(NULL, "ppc4xx-msi");
>+ if (msi_dev) {
>+ err = -ENODEV;
>+ goto out_free;
>+ }
>+
>+ list_for_each_entry(entry, &dev->msi_list, list) {
>+ list_for_each_entry(msi_data, &msi_head, list) {
>+ int_no = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
>+ if(int_no >= 0)
>+ break;
>+ }
>+ if(int_no < 0) {
>+
>+ err = int_no;
>+ pr_debug("%s: fail allocating msi interrupt\n",
>+ __func__);
>+ }
>+ virq = irq_of_parse_and_map(msi_dev, int_no);
>+ if (virq == NO_IRQ) {
>+ dev_err(&dev->dev, "%s: fail mapping irq\n", __func__);
>+ msi_bitmap_free_hwirqs(&msi_data->bitmap, int_no, 1);
>+ err = -ENOSPC;
>+ goto out_free;
>+ }
>+ msi_data->msi_virqs[int_no] = virq;
>+ set_irq_data(virq, (void *)int_no);
>+ dev_dbg(&dev->dev, "%s: virq = %d \n", __func__, virq);
>+
>+ /* Setup msi address space */
>+ msg.address_hi = msi_data->msi_addr_hi;
>+ msg.address_lo = msi_data->msi_addr_lo;
>+
>+ set_irq_msi(virq, entry);
>+ msg.data = int_no;
>+ write_msi_msg(virq, &msg);
>+ }
>+ of_node_put(msi_dev);
>+ return err;
>+
>+out_free:
>+ of_node_put(msi_dev);
>+ return err;
You can move the label up and get rid of the duplicate of_node_put and
return calls.
>+}
>+
>+void ppc4xx_teardown_msi_irqs(struct pci_dev *dev)
>+{
>+ struct msi_desc *entry;
>+ struct ppc4xx_msi *msi_data = dev->dev.platform_data;
>+
>+ dev_dbg(&dev->dev, "PCIE-MSI: tearing down msi irqs\n");
>+
>+ list_for_each_entry(entry, &dev->msi_list, list) {
>+ if (entry->irq == NO_IRQ)
>+ continue;
>+ set_irq_msi(entry->irq, NULL);
>+ msi_bitmap_free_hwirqs(&msi_data->bitmap,
>+ virq_to_hw(entry->irq), 1);
>+ irq_dispose_mapping(entry->irq);
>+ }
>+
>+ return;
>+}
>+
>+static int ppc4xx_msi_check_device(struct pci_dev *pdev, int nvec, int type)
>+{
>+ dev_dbg(&pdev->dev, "PCIE-MSI:%s called. vec %x type %d\n",
>+ __func__, nvec, type);
>+ if (type == PCI_CAP_ID_MSIX)
>+ pr_debug("fslmsi: MSI-X untested, trying anyway.\n");
fslmsi?
>+
>+ return 0;
>+}
>+
>+static int ppc4xx_setup_pcieh_hw(struct platform_device *dev,
>+ struct resource res, struct ppc4xx_msi *msi)
>+{
>+ const u32 *msi_data;
>+ const u32 *msi_mask;
>+ const u32 *sdr_addr;
>+ int err = 0;
>+ dma_addr_t msi_phys;
>+ void *msi_virt;
>+ struct device_node *msi_dev = NULL;
>+
>+ sdr_addr = of_get_property(dev->dev.of_node, "sdr-base", NULL);
>+ if (!sdr_addr)
>+ return -1;
>+
>+ SDR0_WRITE(sdr_addr, (u64)res.start >> 32); /*HIGH addr */
>+ SDR0_WRITE(sdr_addr + 1, res.start & 0xFFFFFFFF); /* Low addr */
>+
>+
>+ msi_dev = of_find_node_by_name(NULL, "ppc4xx-msi");
>+ if (msi_dev) {
>+ err = -ENODEV;
>+ goto error_out;
>+ }
>+ msi->msi_regs = of_iomap(msi_dev, 0);
>+ if (!msi->msi_regs) {
>+ dev_err(&dev->dev, "ioremap problem failed\n");
Should probably read "of_iomap failed".
>+ return -ENOMEM;
>+ }
>+ of_node_put(msi_dev);
>+ dev_dbg(&dev->dev, "PCIE-MSI: msi register mapped 0x%x 0x%x\n",
>+ (u32) (msi->msi_regs + PEIH_TERMADH), (u32) (msi->msi_regs));
>+
>+ msi_virt = dma_alloc_coherent(&dev->dev, 64, &msi_phys, GFP_KERNEL);
This can fail, can't it? Also, where is this actually used?
>+ msi->msi_addr_hi = 0x0;
>+ msi->msi_addr_lo = (u32) msi_phys;
>+ dev_dbg(&dev->dev, "PCIE-MSI: msi address 0x%x \n", msi->msi_addr_lo);
>+
>+ /* Progam the Interrupt handler Termination addr registers */
>+ out_be32(msi->msi_regs + PEIH_TERMADH, msi->msi_addr_hi);
>+ out_be32(msi->msi_regs + PEIH_TERMADL, msi->msi_addr_lo);
>+
>+ msi_data = of_get_property(dev->dev.of_node, "msi-data", NULL);
>+ if (!msi_data) {
>+ err = -1;
>+ goto error_out;
>+ }
>+
>+ msi_mask = of_get_property(dev->dev.of_node, "msi-mask", NULL);
>+ if (!msi_mask) {
>+ err = -1;
>+ goto error_out;
>+ }
I don't see where dma_free_coherent is called to cleanup if either of
those fail.
>+
>+ /* Program MSI Expected data and Mask bits */
>+ out_be32(msi->msi_regs + PEIH_MSIED, *msi_data);
>+ out_be32(msi->msi_regs + PEIH_MSIMK, *msi_mask);
>+
>+ return err;
>+error_out:
>+ return err;
You can just move the label up 2 lines and get rid of one of these
return statements.
>+}
>+
>+static int ppc4xx_of_msi_remove(struct platform_device *dev)
>+{
>+ struct ppc4xx_msi *msi = dev->dev.platform_data;
>+ int i;
>+ int virq;
>+
>+ for(i = 0; i < NR_MSI_IRQS; i++) {
>+ virq = msi->msi_virqs[i];
>+ if (virq != NO_IRQ)
>+ irq_dispose_mapping(virq);
>+ }
>+
>+ if (msi->list.prev != NULL)
>+ list_del(&msi->list);
>+
>+ if (msi->bitmap.bitmap)
>+ msi_bitmap_free(&msi->bitmap);
>+ iounmap(msi->msi_regs);
>+ kfree(msi);
>+
>+ return 0;
>+}
>+
>+static int __devinit ppc4xx_msi_probe(struct platform_device *dev,
>+ const struct of_device_id *match)
>+{
>+ struct ppc4xx_msi *msi;
>+ struct resource res;
>+ int err = 0;
>+
>+ dev_dbg(&dev->dev, "PCIE-MSI: Setting up MSI support...\n");
>+
>+ msi = kzalloc(sizeof(struct ppc4xx_msi), GFP_KERNEL);
>+ if (!msi) {
>+ dev_err(&dev->dev, "No memory for MSI structure\n");
>+ err = -ENOMEM;
>+ goto error_out;
>+ }
>+ dev->dev.platform_data = msi;
>+
>+ /* Get MSI ranges */
>+ err = of_address_to_resource(dev->dev.of_node, 0, &res);
>+ if (err) {
>+ dev_err(&dev->dev, "%s resource error!\n",
>+ dev->dev.of_node->full_name);
>+ goto error_out;
>+ }
>+
>+ if (ppc4xx_setup_pcieh_hw(dev, res, msi))
>+ goto error_out;
>+
>+ err = ppc4xx_msi_init_allocator(dev, msi);
>+ if (err) {
>+ dev_err(&dev->dev, "Error allocating MSI bitmap\n");
>+ goto error_out;
>+ }
>+
>+ list_add_tail(&msi->list, &msi_head);
>+
>+ ppc_md.setup_msi_irqs = ppc4xx_setup_msi_irqs;
>+ ppc_md.teardown_msi_irqs = ppc4xx_teardown_msi_irqs;
>+ ppc_md.msi_check_device = ppc4xx_msi_check_device;
>+ return err;
>+
>+error_out:
>+ ppc4xx_of_msi_remove(dev);
>+ return err;
>+}
>+
>+static struct of_platform_driver ppc4xx_msi_driver = {
>+ .driver = {
>+ .name = "ppc4xx-msi",
>+ .owner = THIS_MODULE,
>+ },
>+ .probe = ppc4xx_msi_probe,
>+ .remove = ppc4xx_of_msi_remove,
>+};
>+
>+static __init int ppc4xx_msi_init(void)
>+{
>+ return of_register_platform_driver(&ppc4xx_msi_driver);
>+}
>+
>+subsys_initcall(ppc4xx_msi_init);
>--
>1.6.1.rc3
>
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