From 05af7bd2d75e5098021864d83fbb831111755fa0 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 8 May 2007 12:58:37 +1000 Subject: [PATCH] [POWERPC] MPIC U3/U4 MSI backend MPIC U3/U4 MSI backend. Based on code from Segher, heavily hacked by me. This only deals with MSI on U3/U4 MPICs, aka. CPC 9x5. If we find a U3/U4 then we enable this backend, ie. take over the ppc_md MSI hooks. We might need more elaborate logic in future to decide which backend is enabled. We need our own irq_chip so that we can do MSI masking/unmasking on the device itself. We also need to mask explicitly on shutdown to make sure we don't get bitten by lazy-disable semantics. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras --- arch/powerpc/sysdev/Makefile | 2 +- arch/powerpc/sysdev/mpic.c | 12 +- arch/powerpc/sysdev/mpic.h | 11 ++ arch/powerpc/sysdev/mpic_u3msi.c | 186 +++++++++++++++++++++++++++++++ 4 files changed, 205 insertions(+), 6 deletions(-) create mode 100644 arch/powerpc/sysdev/mpic_u3msi.c diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile index a170205329..d16167977f 100644 --- a/arch/powerpc/sysdev/Makefile +++ b/arch/powerpc/sysdev/Makefile @@ -2,7 +2,7 @@ ifeq ($(CONFIG_PPC64),y) EXTRA_CFLAGS += -mno-minimal-toc endif -mpic-msi-obj-$(CONFIG_PCI_MSI) += mpic_msi.o +mpic-msi-obj-$(CONFIG_PCI_MSI) += mpic_msi.o mpic_u3msi.o obj-$(CONFIG_MPIC) += mpic.o $(mpic-msi-obj-y) obj-$(CONFIG_PPC_INDIRECT_PCI) += indirect_pci.o diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c index fc0428aea0..4fd2bec899 100644 --- a/arch/powerpc/sysdev/mpic.c +++ b/arch/powerpc/sysdev/mpic.c @@ -618,7 +618,7 @@ static irqreturn_t mpic_ipi_action(int irq, void *dev_id) */ -static void mpic_unmask_irq(unsigned int irq) +void mpic_unmask_irq(unsigned int irq) { unsigned int loops = 100000; struct mpic *mpic = mpic_from_irq(irq); @@ -638,7 +638,7 @@ static void mpic_unmask_irq(unsigned int irq) } while(mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI)) & MPIC_VECPRI_MASK); } -static void mpic_mask_irq(unsigned int irq) +void mpic_mask_irq(unsigned int irq) { unsigned int loops = 100000; struct mpic *mpic = mpic_from_irq(irq); @@ -659,7 +659,7 @@ static void mpic_mask_irq(unsigned int irq) } while(!(mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI)) & MPIC_VECPRI_MASK)); } -static void mpic_end_irq(unsigned int irq) +void mpic_end_irq(unsigned int irq) { struct mpic *mpic = mpic_from_irq(irq); @@ -792,7 +792,7 @@ static unsigned int mpic_type_to_vecpri(struct mpic *mpic, unsigned int type) } } -static int mpic_set_irq_type(unsigned int virq, unsigned int flow_type) +int mpic_set_irq_type(unsigned int virq, unsigned int flow_type) { struct mpic *mpic = mpic_from_irq(virq); unsigned int src = mpic_irq_to_hw(virq); @@ -1203,8 +1203,10 @@ void __init mpic_init(struct mpic *mpic) /* Do the HT PIC fixups on U3 broken mpic */ DBG("MPIC flags: %x\n", mpic->flags); - if ((mpic->flags & MPIC_U3_HT_IRQS) && (mpic->flags & MPIC_PRIMARY)) + if ((mpic->flags & MPIC_U3_HT_IRQS) && (mpic->flags & MPIC_PRIMARY)) { mpic_scan_ht_pics(mpic); + mpic_u3msi_init(mpic); + } for (i = 0; i < mpic->num_sources; i++) { /* start with vector = source number, and masked */ diff --git a/arch/powerpc/sysdev/mpic.h b/arch/powerpc/sysdev/mpic.h index 87cb2aea2f..3a1c3d2c59 100644 --- a/arch/powerpc/sysdev/mpic.h +++ b/arch/powerpc/sysdev/mpic.h @@ -16,12 +16,23 @@ extern void mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq); extern int mpic_msi_init_allocator(struct mpic *mpic); extern irq_hw_number_t mpic_msi_alloc_hwirqs(struct mpic *mpic, int num); extern void mpic_msi_free_hwirqs(struct mpic *mpic, int offset, int num); +extern int mpic_u3msi_init(struct mpic *mpic); #else static inline void mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq) { return; } + +static inline int mpic_u3msi_init(struct mpic *mpic) +{ + return -1; +} #endif +extern int mpic_set_irq_type(unsigned int virq, unsigned int flow_type); +extern void mpic_end_irq(unsigned int irq); +extern void mpic_mask_irq(unsigned int irq); +extern void mpic_unmask_irq(unsigned int irq); + #endif /* _POWERPC_SYSDEV_MPIC_H */ diff --git a/arch/powerpc/sysdev/mpic_u3msi.c b/arch/powerpc/sysdev/mpic_u3msi.c new file mode 100644 index 0000000000..305b864c25 --- /dev/null +++ b/arch/powerpc/sysdev/mpic_u3msi.c @@ -0,0 +1,186 @@ +/* + * Copyright 2006, Segher Boessenkool, IBM Corporation. + * Copyright 2006-2007, Michael Ellerman, 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; version 2 of the + * License. + * + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "mpic.h" + +/* A bit ugly, can we get this from the pci_dev somehow? */ +static struct mpic *msi_mpic; + +static void mpic_u3msi_mask_irq(unsigned int irq) +{ + mask_msi_irq(irq); + mpic_mask_irq(irq); +} + +static void mpic_u3msi_unmask_irq(unsigned int irq) +{ + mpic_unmask_irq(irq); + unmask_msi_irq(irq); +} + +static struct irq_chip mpic_u3msi_chip = { + .shutdown = mpic_u3msi_mask_irq, + .mask = mpic_u3msi_mask_irq, + .unmask = mpic_u3msi_unmask_irq, + .eoi = mpic_end_irq, + .set_type = mpic_set_irq_type, + .typename = "MPIC-U3MSI", +}; + +static u64 read_ht_magic_addr(struct pci_dev *pdev, unsigned int pos) +{ + u8 flags; + u32 tmp; + u64 addr; + + pci_read_config_byte(pdev, pos + HT_MSI_FLAGS, &flags); + + if (flags & HT_MSI_FLAGS_FIXED) + return HT_MSI_FIXED_ADDR; + + pci_read_config_dword(pdev, pos + HT_MSI_ADDR_LO, &tmp); + addr = tmp & HT_MSI_ADDR_LO_MASK; + pci_read_config_dword(pdev, pos + HT_MSI_ADDR_HI, &tmp); + addr = addr | ((u64)tmp << 32); + + return addr; +} + +static u64 find_ht_magic_addr(struct pci_dev *pdev) +{ + struct pci_bus *bus; + unsigned int pos; + + for (bus = pdev->bus; bus; bus = bus->parent) { + pos = pci_find_ht_capability(bus->self, HT_CAPTYPE_MSI_MAPPING); + if (pos) + return read_ht_magic_addr(bus->self, pos); + } + + return 0; +} + +static int u3msi_msi_check_device(struct pci_dev *pdev, int nvec, int type) +{ + if (type == PCI_CAP_ID_MSIX) + pr_debug("u3msi: MSI-X untested, trying anyway.\n"); + + /* If we can't find a magic address then MSI ain't gonna work */ + if (find_ht_magic_addr(pdev) == 0) { + pr_debug("u3msi: no magic address found for %s\n", + pci_name(pdev)); + return -ENXIO; + } + + return 0; +} + +static void u3msi_teardown_msi_irqs(struct pci_dev *pdev) +{ + struct msi_desc *entry; + + list_for_each_entry(entry, &pdev->msi_list, list) { + if (entry->irq == NO_IRQ) + continue; + + set_irq_msi(entry->irq, NULL); + mpic_msi_free_hwirqs(msi_mpic, virq_to_hw(entry->irq), 1); + irq_dispose_mapping(entry->irq); + } + + return; +} + +static void u3msi_compose_msi_msg(struct pci_dev *pdev, int virq, + struct msi_msg *msg) +{ + u64 addr; + + addr = find_ht_magic_addr(pdev); + msg->address_lo = addr & 0xFFFFFFFF; + msg->address_hi = addr >> 32; + msg->data = virq_to_hw(virq); + + pr_debug("u3msi: allocated virq 0x%x (hw 0x%lx) at address 0x%lx\n", + virq, virq_to_hw(virq), addr); +} + +static int u3msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type) +{ + irq_hw_number_t hwirq; + int rc; + unsigned int virq; + struct msi_desc *entry; + struct msi_msg msg; + + list_for_each_entry(entry, &pdev->msi_list, list) { + hwirq = mpic_msi_alloc_hwirqs(msi_mpic, 1); + if (hwirq < 0) { + rc = hwirq; + pr_debug("u3msi: failed allocating hwirq\n"); + goto out_free; + } + + virq = irq_create_mapping(msi_mpic->irqhost, hwirq); + if (virq == NO_IRQ) { + pr_debug("u3msi: failed mapping hwirq 0x%lx\n", hwirq); + mpic_msi_free_hwirqs(msi_mpic, hwirq, 1); + rc = -ENOSPC; + goto out_free; + } + + set_irq_msi(virq, entry); + set_irq_chip(virq, &mpic_u3msi_chip); + set_irq_type(virq, IRQ_TYPE_EDGE_RISING); + + u3msi_compose_msi_msg(pdev, virq, &msg); + write_msi_msg(virq, &msg); + + hwirq++; + } + + return 0; + + out_free: + u3msi_teardown_msi_irqs(pdev); + return rc; +} + +int mpic_u3msi_init(struct mpic *mpic) +{ + int rc; + + rc = mpic_msi_init_allocator(mpic); + if (rc) { + pr_debug("u3msi: Error allocating bitmap!\n"); + return rc; + } + + pr_debug("u3msi: Registering MPIC U3 MSI callbacks.\n"); + + BUG_ON(msi_mpic); + msi_mpic = mpic; + + WARN_ON(ppc_md.setup_msi_irqs); + ppc_md.setup_msi_irqs = u3msi_setup_msi_irqs; + ppc_md.teardown_msi_irqs = u3msi_teardown_msi_irqs; + ppc_md.msi_check_device = u3msi_msi_check_device; + + return 0; +} -- 2.20.1