https://github.com/torvalds/linux
Tip revision: 48778464bb7d346b47157d21ffde2af6b2d39110 authored by Linus Torvalds on 21 June 2020, 22:45:29 UTC
Linux 5.8-rc2
Linux 5.8-rc2
Tip revision: 4877846
msi-xlp.c
/*
* 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 (cpu_is_xlp9xx() ? 128 : 32)
#define XLP_MSIXVEC_PER_LINK (cpu_is_xlp9xx() ? 32 : 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;
}
/* get the link MSI vector from irq number */
static inline int nlm_irq_msivec(int irq)
{
return (irq - NLM_MSI_VEC_BASE) % XLP_MSIVEC_PER_LINK;
}
/* get the link from the irq number */
static inline int nlm_irq_msilink(int irq)
{
int total_msivec = XLP_MSIVEC_PER_LINK * PCIE_NLINKS;
return ((irq - NLM_MSI_VEC_BASE) % total_msivec) /
XLP_MSIVEC_PER_LINK;
}
/*
* For XLP 8xx/4xx/3xx/2xx, 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.
* On XLP 9xx, there are 32 vectors per link, and the interrupts are
* not routed thru PIC, so we can use all 128 MSI-X vectors.
*/
static inline int nlm_link_msixirq(int link, int bit)
{
return NLM_MSIX_VEC_BASE + link * XLP_MSIXVEC_PER_LINK + bit;
}
/* get the link MSI vector from irq number */
static inline int nlm_irq_msixvec(int irq)
{
return (irq - NLM_MSIX_VEC_BASE) % XLP_MSIXVEC_TOTAL;
}
/* get the link from MSIX vec */
static inline int nlm_irq_msixlink(int msixvec)
{
return msixvec / 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_chip_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;
if (cpu_is_xlp9xx())
nlm_write_reg(md->lnkbase, PCIE_9XX_MSI_EN,
md->msi_enabled_mask);
else
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_chip_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);
if (cpu_is_xlp9xx())
nlm_write_reg(md->lnkbase, PCIE_9XX_MSI_EN,
md->msi_enabled_mask);
else
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_chip_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 */
if (cpu_is_xlp9xx())
nlm_write_reg(md->lnkbase, PCIE_9XX_MSI_STATUS, 1u << vec);
else
nlm_write_reg(md->lnkbase, PCIE_MSI_STATUS, 1u << vec);
}
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,
};
/*
* XLP8XX/4XX/3XX/2XX:
* 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
*
* XLP9XX:
* 32 MSI-X vectors are available per link, and the interrupts are not routed
* thru the PIC. PIC ack not needed.
*
* Enable and disable done using standard MSI functions.
*/
static void xlp_msix_mask_ack(struct irq_data *d)
{
struct xlp_msi_data *md;
int link, msixvec;
uint32_t status_reg, bit;
msixvec = nlm_irq_msixvec(d->irq);
link = nlm_irq_msixlink(msixvec);
pci_msi_mask_irq(d);
md = irq_data_get_irq_chip_data(d);
/* Ack MSI on bridge */
if (cpu_is_xlp9xx()) {
status_reg = PCIE_9XX_MSIX_STATUSX(link);
bit = msixvec % XLP_MSIXVEC_PER_LINK;
} else {
status_reg = PCIE_MSIX_STATUS;
bit = msixvec;
}
nlm_write_reg(md->lnkbase, status_reg, 1u << bit);
if (!cpu_is_xlp9xx())
nlm_pic_ack(md->node->picbase,
PIC_IRT_PCIE_MSIX_INDEX(msixvec));
}
static struct irq_chip xlp_msix_chip = {
.name = "XLP-MSIX",
.irq_enable = pci_msi_unmask_irq,
.irq_disable = pci_msi_mask_irq,
.irq_mask_ack = xlp_msix_mask_ack,
.irq_unmask = pci_msi_unmask_irq,
};
void arch_teardown_msi_irq(unsigned int 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;
if (cpu_is_xlp9xx()) {
val = nlm_read_reg(lnkbase, PCIE_9XX_INT_EN0);
if ((val & 0x200) == 0) {
val |= 0x200; /* MSI Interrupt enable */
nlm_write_reg(lnkbase, PCIE_9XX_INT_EN0, val);
}
} else {
val = nlm_read_reg(lnkbase, PCIE_INT_EN0);
if ((val & 0x200) == 0) {
val |= 0x200;
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_chip_data(xirq);
msiaddr = MSI_LINK_ADDR(node, link);
spin_lock_irqsave(&md->msi_lock, flags);
if (md->msi_alloc_mask == 0) {
xlp_config_link_msi(lnkbase, lirq, msiaddr);
/* switch the link IRQ to MSI range */
if (cpu_is_xlp9xx())
irt = PIC_9XX_IRT_PCIE_LINK_INDEX(link);
else
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_threads_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)
return ret;
pci_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);
}
if (cpu_is_xlp9xx()) {
val = nlm_read_reg(lnkbase, PCIE_9XX_INT_EN0);
if ((val & 0x200) == 0) {
val |= 0x200; /* MSI Interrupt enable */
nlm_write_reg(lnkbase, PCIE_9XX_INT_EN0, val);
}
} else {
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);
if (cpu_is_xlp9xx()) {
/* MSI-X addresses */
nlm_write_reg(lnkbase, PCIE_9XX_BRIDGE_MSIX_ADDR_BASE,
msixaddr >> 8);
nlm_write_reg(lnkbase, PCIE_9XX_BRIDGE_MSIX_ADDR_LIMIT,
(msixaddr + MSI_ADDR_SZ) >> 8);
} else {
/* 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_chip_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)
return ret;
pci_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, val;
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_chip_data(i, md);
}
for (i = 0; i < XLP_MSIXVEC_PER_LINK ; i++) {
if (cpu_is_xlp9xx()) {
val = ((node * nlm_threads_per_node()) << 7 |
PIC_PCIE_MSIX_IRQ(link) << 1 | 0 << 0);
nlm_write_pcie_reg(md->lnkbase, PCIE_9XX_MSIX_VECX(i +
(link * XLP_MSIXVEC_PER_LINK)), val);
} else {
/* 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_threads_per_node(), 1);
}
/* 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_chip_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_chip_data(irqbase);
if (cpu_is_xlp9xx())
status = nlm_read_reg(md->lnkbase, PCIE_9XX_MSI_STATUS) &
md->msi_enabled_mask;
else
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;
}
/* Ack at eirr and PIC */
ack_c0_eirr(PIC_PCIE_LINK_MSI_IRQ(link));
if (cpu_is_xlp9xx())
nlm_pic_ack(md->node->picbase,
PIC_9XX_IRT_PCIE_LINK_INDEX(link));
else
nlm_pic_ack(md->node->picbase, PIC_IRT_PCIE_LINK_INDEX(link));
}
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_chip_data(irqbase);
if (cpu_is_xlp9xx())
status = nlm_read_reg(md->lnkbase, PCIE_9XX_MSIX_STATUSX(link));
else
status = nlm_read_reg(md->lnkbase, PCIE_MSIX_STATUS);
/* narrow it down to the MSI-x vectors for our link */
if (!cpu_is_xlp9xx())
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;
}
/* Ack at eirr and PIC */
ack_c0_eirr(PIC_PCIE_MSIX_IRQ(link));
}