diff options
author | Jayachandran C <jchandra@broadcom.com> | 2013-12-21 16:52:13 +0530 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2014-01-24 22:39:46 +0100 |
commit | c24a8a7a99885d5b986f38f6631f69e7794a3e5e (patch) | |
tree | a0d6702fc1c45cba157a5734215c509fa4b216c6 /arch/mips/pci/msi-xlp.c | |
parent | 27547abf36af7964b53a8c9265e266df692d4806 (diff) |
MIPS: Netlogic: Add MSI support for XLP
Add MSI chip and MSIX chip definitions.
For MSI, we map the link interrupt to a MSI link IRQ which will
do a second level of dispatch based on the MSI status register.
The MSI chip definitions use the MSI enable register to enable
and disable the MSI irqs.
For MSI-X, we split the 32 available MSI-X vectors across the
four PCIe links (8 each). These PIC interrupts generate an IRQ
per link which uses a second level dispatch as well.
The MSI-X chip definition uses the standard functions to enable
and disable interrupts.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6270/
Diffstat (limited to 'arch/mips/pci/msi-xlp.c')
-rw-r--r-- | arch/mips/pci/msi-xlp.c | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/arch/mips/pci/msi-xlp.c b/arch/mips/pci/msi-xlp.c new file mode 100644 index 000000000000..66a244a73a82 --- /dev/null +++ b/arch/mips/pci/msi-xlp.c @@ -0,0 +1,494 @@ +/* + * Copyright (c) 2003-2012 Broadcom Corporation + * All Rights Reserved + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the Broadcom + * license below: + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY BROADCOM ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL BROADCOM OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN + * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <linux/types.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/msi.h> +#include <linux/mm.h> +#include <linux/irq.h> +#include <linux/irqdesc.h> +#include <linux/console.h> + +#include <asm/io.h> + +#include <asm/netlogic/interrupt.h> +#include <asm/netlogic/haldefs.h> +#include <asm/netlogic/common.h> +#include <asm/netlogic/mips-extns.h> + +#include <asm/netlogic/xlp-hal/iomap.h> +#include <asm/netlogic/xlp-hal/xlp.h> +#include <asm/netlogic/xlp-hal/pic.h> +#include <asm/netlogic/xlp-hal/pcibus.h> +#include <asm/netlogic/xlp-hal/bridge.h> + +#define XLP_MSIVEC_PER_LINK 32 +#define XLP_MSIXVEC_TOTAL 32 +#define XLP_MSIXVEC_PER_LINK 8 + +/* 128 MSI irqs per node, mapped starting at NLM_MSI_VEC_BASE */ +static inline int nlm_link_msiirq(int link, int msivec) +{ + return NLM_MSI_VEC_BASE + link * XLP_MSIVEC_PER_LINK + msivec; +} + +static inline int nlm_irq_msivec(int irq) +{ + return irq % XLP_MSIVEC_PER_LINK; +} + +static inline int nlm_irq_msilink(int irq) +{ + return (irq % (XLP_MSIVEC_PER_LINK * PCIE_NLINKS)) / + XLP_MSIVEC_PER_LINK; +} + +/* + * Only 32 MSI-X vectors are possible because there are only 32 PIC + * interrupts for MSI. We split them statically and use 8 MSI-X vectors + * per link - this keeps the allocation and lookup simple. + */ +static inline int nlm_link_msixirq(int link, int bit) +{ + return NLM_MSIX_VEC_BASE + link * XLP_MSIXVEC_PER_LINK + bit; +} + +static inline int nlm_irq_msixvec(int irq) +{ + return irq % XLP_MSIXVEC_TOTAL; /* works when given xirq */ +} + +static inline int nlm_irq_msixlink(int irq) +{ + return nlm_irq_msixvec(irq) / XLP_MSIXVEC_PER_LINK; +} + +/* + * Per link MSI and MSI-X information, set as IRQ handler data for + * MSI and MSI-X interrupts. + */ +struct xlp_msi_data { + struct nlm_soc_info *node; + uint64_t lnkbase; + uint32_t msi_enabled_mask; + uint32_t msi_alloc_mask; + uint32_t msix_alloc_mask; + spinlock_t msi_lock; +}; + +/* + * MSI Chip definitions + * + * On XLP, there is a PIC interrupt associated with each PCIe link on the + * chip (which appears as a PCI bridge to us). This gives us 32 MSI irqa + * per link and 128 overall. + * + * When a device connected to the link raises a MSI interrupt, we get a + * link interrupt and we then have to look at PCIE_MSI_STATUS register at + * the bridge to map it to the IRQ + */ +static void xlp_msi_enable(struct irq_data *d) +{ + struct xlp_msi_data *md = irq_data_get_irq_handler_data(d); + unsigned long flags; + int vec; + + vec = nlm_irq_msivec(d->irq); + spin_lock_irqsave(&md->msi_lock, flags); + md->msi_enabled_mask |= 1u << vec; + nlm_write_reg(md->lnkbase, PCIE_MSI_EN, md->msi_enabled_mask); + spin_unlock_irqrestore(&md->msi_lock, flags); +} + +static void xlp_msi_disable(struct irq_data *d) +{ + struct xlp_msi_data *md = irq_data_get_irq_handler_data(d); + unsigned long flags; + int vec; + + vec = nlm_irq_msivec(d->irq); + spin_lock_irqsave(&md->msi_lock, flags); + md->msi_enabled_mask &= ~(1u << vec); + nlm_write_reg(md->lnkbase, PCIE_MSI_EN, md->msi_enabled_mask); + spin_unlock_irqrestore(&md->msi_lock, flags); +} + +static void xlp_msi_mask_ack(struct irq_data *d) +{ + struct xlp_msi_data *md = irq_data_get_irq_handler_data(d); + int link, vec; + + link = nlm_irq_msilink(d->irq); + vec = nlm_irq_msivec(d->irq); + xlp_msi_disable(d); + + /* Ack MSI on bridge */ + nlm_write_reg(md->lnkbase, PCIE_MSI_STATUS, 1u << vec); + + /* Ack at eirr and PIC */ + ack_c0_eirr(PIC_PCIE_LINK_MSI_IRQ(link)); + nlm_pic_ack(md->node->picbase, PIC_IRT_PCIE_LINK_INDEX(link)); +} + +static struct irq_chip xlp_msi_chip = { + .name = "XLP-MSI", + .irq_enable = xlp_msi_enable, + .irq_disable = xlp_msi_disable, + .irq_mask_ack = xlp_msi_mask_ack, + .irq_unmask = xlp_msi_enable, +}; + +/* + * The MSI-X interrupt handling is different from MSI, there are 32 + * MSI-X interrupts generated by the PIC and each of these correspond + * to a MSI-X vector (0-31) that can be assigned. + * + * We divide the MSI-X vectors to 8 per link and do a per-link + * allocation + * + * Enable and disable done using standard MSI functions. + */ +static void xlp_msix_mask_ack(struct irq_data *d) +{ + struct xlp_msi_data *md = irq_data_get_irq_handler_data(d); + int link, msixvec; + + msixvec = nlm_irq_msixvec(d->irq); + link = nlm_irq_msixlink(d->irq); + mask_msi_irq(d); + + /* Ack MSI on bridge */ + nlm_write_reg(md->lnkbase, PCIE_MSIX_STATUS, 1u << msixvec); + + /* Ack at eirr and PIC */ + ack_c0_eirr(PIC_PCIE_MSIX_IRQ(link)); + nlm_pic_ack(md->node->picbase, PIC_IRT_PCIE_MSIX_INDEX(msixvec)); +} + +static struct irq_chip xlp_msix_chip = { + .name = "XLP-MSIX", + .irq_enable = unmask_msi_irq, + .irq_disable = mask_msi_irq, + .irq_mask_ack = xlp_msix_mask_ack, + .irq_unmask = unmask_msi_irq, +}; + +void destroy_irq(unsigned int irq) +{ + /* nothing to do yet */ +} + +void arch_teardown_msi_irq(unsigned int irq) +{ + destroy_irq(irq); +} + +/* + * Setup a PCIe link for MSI. By default, the links are in + * legacy interrupt mode. We will switch them to MSI mode + * at the first MSI request. + */ +static void xlp_config_link_msi(uint64_t lnkbase, int lirq, uint64_t msiaddr) +{ + u32 val; + + val = nlm_read_reg(lnkbase, PCIE_INT_EN0); + if ((val & 0x200) == 0) { + val |= 0x200; /* MSI Interrupt enable */ + nlm_write_reg(lnkbase, PCIE_INT_EN0, val); + } + + val = nlm_read_reg(lnkbase, 0x1); /* CMD */ + if ((val & 0x0400) == 0) { + val |= 0x0400; + nlm_write_reg(lnkbase, 0x1, val); + } + + /* Update IRQ in the PCI irq reg */ + val = nlm_read_pci_reg(lnkbase, 0xf); + val &= ~0x1fu; + val |= (1 << 8) | lirq; + nlm_write_pci_reg(lnkbase, 0xf, val); + + /* MSI addr */ + nlm_write_reg(lnkbase, PCIE_BRIDGE_MSI_ADDRH, msiaddr >> 32); + nlm_write_reg(lnkbase, PCIE_BRIDGE_MSI_ADDRL, msiaddr & 0xffffffff); + + /* MSI cap for bridge */ + val = nlm_read_reg(lnkbase, PCIE_BRIDGE_MSI_CAP); + if ((val & (1 << 16)) == 0) { + val |= 0xb << 16; /* mmc32, msi enable */ + nlm_write_reg(lnkbase, PCIE_BRIDGE_MSI_CAP, val); + } +} + +/* + * Allocate a MSI vector on a link + */ +static int xlp_setup_msi(uint64_t lnkbase, int node, int link, + struct msi_desc *desc) +{ + struct xlp_msi_data *md; + struct msi_msg msg; + unsigned long flags; + int msivec, irt, lirq, xirq, ret; + uint64_t msiaddr; + + /* Get MSI data for the link */ + lirq = PIC_PCIE_LINK_MSI_IRQ(link); + xirq = nlm_irq_to_xirq(node, nlm_link_msiirq(link, 0)); + md = irq_get_handler_data(xirq); + msiaddr = MSI_LINK_ADDR(node, link); + + spin_lock_irqsave(&md->msi_lock, flags); + if (md->msi_alloc_mask == 0) { + /* switch the link IRQ to MSI range */ + xlp_config_link_msi(lnkbase, lirq, msiaddr); + irt = PIC_IRT_PCIE_LINK_INDEX(link); + nlm_setup_pic_irq(node, lirq, lirq, irt); + nlm_pic_init_irt(nlm_get_node(node)->picbase, irt, lirq, + node * NLM_CPUS_PER_NODE, 1 /*en */); + } + + /* allocate a MSI vec, and tell the bridge about it */ + msivec = fls(md->msi_alloc_mask); + if (msivec == XLP_MSIVEC_PER_LINK) { + spin_unlock_irqrestore(&md->msi_lock, flags); + return -ENOMEM; + } + md->msi_alloc_mask |= (1u << msivec); + spin_unlock_irqrestore(&md->msi_lock, flags); + + msg.address_hi = msiaddr >> 32; + msg.address_lo = msiaddr & 0xffffffff; + msg.data = 0xc00 | msivec; + + xirq = xirq + msivec; /* msi mapped to global irq space */ + ret = irq_set_msi_desc(xirq, desc); + if (ret < 0) { + destroy_irq(xirq); + return ret; + } + + write_msi_msg(xirq, &msg); + return 0; +} + +/* + * Switch a link to MSI-X mode + */ +static void xlp_config_link_msix(uint64_t lnkbase, int lirq, uint64_t msixaddr) +{ + u32 val; + + val = nlm_read_reg(lnkbase, 0x2C); + if ((val & 0x80000000U) == 0) { + val |= 0x80000000U; + nlm_write_reg(lnkbase, 0x2C, val); + } + val = nlm_read_reg(lnkbase, PCIE_INT_EN0); + if ((val & 0x200) == 0) { + val |= 0x200; /* MSI Interrupt enable */ + nlm_write_reg(lnkbase, PCIE_INT_EN0, val); + } + + val = nlm_read_reg(lnkbase, 0x1); /* CMD */ + if ((val & 0x0400) == 0) { + val |= 0x0400; + nlm_write_reg(lnkbase, 0x1, val); + } + + /* Update IRQ in the PCI irq reg */ + val = nlm_read_pci_reg(lnkbase, 0xf); + val &= ~0x1fu; + val |= (1 << 8) | lirq; + nlm_write_pci_reg(lnkbase, 0xf, val); + + /* MSI-X addresses */ + nlm_write_reg(lnkbase, PCIE_BRIDGE_MSIX_ADDR_BASE, msixaddr >> 8); + nlm_write_reg(lnkbase, PCIE_BRIDGE_MSIX_ADDR_LIMIT, + (msixaddr + MSI_ADDR_SZ) >> 8); +} + +/* + * Allocate a MSI-X vector + */ +static int xlp_setup_msix(uint64_t lnkbase, int node, int link, + struct msi_desc *desc) +{ + struct xlp_msi_data *md; + struct msi_msg msg; + unsigned long flags; + int t, msixvec, lirq, xirq, ret; + uint64_t msixaddr; + + /* Get MSI data for the link */ + lirq = PIC_PCIE_MSIX_IRQ(link); + xirq = nlm_irq_to_xirq(node, nlm_link_msixirq(link, 0)); + md = irq_get_handler_data(xirq); + msixaddr = MSIX_LINK_ADDR(node, link); + + spin_lock_irqsave(&md->msi_lock, flags); + /* switch the PCIe link to MSI-X mode at the first alloc */ + if (md->msix_alloc_mask == 0) + xlp_config_link_msix(lnkbase, lirq, msixaddr); + + /* allocate a MSI-X vec, and tell the bridge about it */ + t = fls(md->msix_alloc_mask); + if (t == XLP_MSIXVEC_PER_LINK) { + spin_unlock_irqrestore(&md->msi_lock, flags); + return -ENOMEM; + } + md->msix_alloc_mask |= (1u << t); + spin_unlock_irqrestore(&md->msi_lock, flags); + + xirq += t; + msixvec = nlm_irq_msixvec(xirq); + msg.address_hi = msixaddr >> 32; + msg.address_lo = msixaddr & 0xffffffff; + msg.data = 0xc00 | msixvec; + + ret = irq_set_msi_desc(xirq, desc); + if (ret < 0) { + destroy_irq(xirq); + return ret; + } + + write_msi_msg(xirq, &msg); + return 0; +} + +int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) +{ + struct pci_dev *lnkdev; + uint64_t lnkbase; + int node, link, slot; + + lnkdev = xlp_get_pcie_link(dev); + if (lnkdev == NULL) { + dev_err(&dev->dev, "Could not find bridge\n"); + return 1; + } + slot = PCI_SLOT(lnkdev->devfn); + link = PCI_FUNC(lnkdev->devfn); + node = slot / 8; + lnkbase = nlm_get_pcie_base(node, link); + + if (desc->msi_attrib.is_msix) + return xlp_setup_msix(lnkbase, node, link, desc); + else + return xlp_setup_msi(lnkbase, node, link, desc); +} + +void __init xlp_init_node_msi_irqs(int node, int link) +{ + struct nlm_soc_info *nodep; + struct xlp_msi_data *md; + int irq, i, irt, msixvec; + + pr_info("[%d %d] Init node PCI IRT\n", node, link); + nodep = nlm_get_node(node); + + /* Alloc an MSI block for the link */ + md = kzalloc(sizeof(*md), GFP_KERNEL); + spin_lock_init(&md->msi_lock); + md->msi_enabled_mask = 0; + md->msi_alloc_mask = 0; + md->msix_alloc_mask = 0; + md->node = nodep; + md->lnkbase = nlm_get_pcie_base(node, link); + + /* extended space for MSI interrupts */ + irq = nlm_irq_to_xirq(node, nlm_link_msiirq(link, 0)); + for (i = irq; i < irq + XLP_MSIVEC_PER_LINK; i++) { + irq_set_chip_and_handler(i, &xlp_msi_chip, handle_level_irq); + irq_set_handler_data(i, md); + } + + for (i = 0; i < XLP_MSIXVEC_PER_LINK; i++) { + /* Initialize MSI-X irts to generate one interrupt per link */ + msixvec = link * XLP_MSIXVEC_PER_LINK + i; + irt = PIC_IRT_PCIE_MSIX_INDEX(msixvec); + nlm_pic_init_irt(nodep->picbase, irt, PIC_PCIE_MSIX_IRQ(link), + node * NLM_CPUS_PER_NODE, 1 /* enable */); + + /* Initialize MSI-X extended irq space for the link */ + irq = nlm_irq_to_xirq(node, nlm_link_msixirq(link, i)); + irq_set_chip_and_handler(irq, &xlp_msix_chip, handle_level_irq); + irq_set_handler_data(irq, md); + } + +} + +void nlm_dispatch_msi(int node, int lirq) +{ + struct xlp_msi_data *md; + int link, i, irqbase; + u32 status; + + link = lirq - PIC_PCIE_LINK_MSI_IRQ_BASE; + irqbase = nlm_irq_to_xirq(node, nlm_link_msiirq(link, 0)); + md = irq_get_handler_data(irqbase); + status = nlm_read_reg(md->lnkbase, PCIE_MSI_STATUS) & + md->msi_enabled_mask; + while (status) { + i = __ffs(status); + do_IRQ(irqbase + i); + status &= status - 1; + } +} + +void nlm_dispatch_msix(int node, int lirq) +{ + struct xlp_msi_data *md; + int link, i, irqbase; + u32 status; + + link = lirq - PIC_PCIE_MSIX_IRQ_BASE; + irqbase = nlm_irq_to_xirq(node, nlm_link_msixirq(link, 0)); + md = irq_get_handler_data(irqbase); + status = nlm_read_reg(md->lnkbase, PCIE_MSIX_STATUS); + + /* narrow it down to the MSI-x vectors for our link */ + status = (status >> (link * XLP_MSIXVEC_PER_LINK)) & + ((1 << XLP_MSIXVEC_PER_LINK) - 1); + + while (status) { + i = __ffs(status); + do_IRQ(irqbase + i); + status &= status - 1; + } +} |