From a6b133efc9e704461a96bc533c5977b579623d03 Mon Sep 17 00:00:00 2001
From: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
Date: Wed, 15 Jan 2014 10:37:33 +0100
Subject: [PATCH] kernel: built-in support for the VIC interrupt controller
---
kernel/Makefile | 1 +
kernel/hw/vic_regs.h | 87 +++++++++++++++++++
kernel/spec-fmc.c | 108 ++++++++++++++++++++---
kernel/spec-vic.c | 200 +++++++++++++++++++++++++++++++++++++++++++
kernel/spec.h | 9 ++
5 files changed, 394 insertions(+), 11 deletions(-)
create mode 100644 kernel/hw/vic_regs.h
create mode 100644 kernel/spec-vic.c
diff --git a/kernel/Makefile b/kernel/Makefile
index e2565d4..d027e9f 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_WR_NIC) += wr-nic.o
spec-y = spec-pci.o
spec-y += spec-fmc.o
spec-y += spec-i2c.o
+spec-y += spec-vic.o
spec-y += loader-ll.o
spec-y += spec-gpio-no.o
spec-$(CONFIG_GPIOLIB) += spec-gpio.o
diff --git a/kernel/hw/vic_regs.h b/kernel/hw/vic_regs.h
new file mode 100644
index 0000000..3d7e5ff
--- /dev/null
+++ b/kernel/hw/vic_regs.h
@@ -0,0 +1,87 @@
+/*
+ Register definitions for slave core: Vectored Interrupt Controller (VIC)
+
+ * File : vic_regs.h
+ * Author : auto-generated by wbgen2 from wb_slave_vic.wb
+ * Created : Thu Oct 25 16:47:27 2012
+ * Standard : ANSI C
+
+ THIS FILE WAS GENERATED BY wbgen2 FROM SOURCE FILE wb_slave_vic.wb
+ DO NOT HAND-EDIT UNLESS IT'S ABSOLUTELY NECESSARY!
+
+*/
+
+#ifndef __WBGEN2_REGDEFS_WB_SLAVE_VIC_WB
+#define __WBGEN2_REGDEFS_WB_SLAVE_VIC_WB
+
+#include <linux/types.h>
+
+#if defined( __GNUC__)
+#define PACKED __attribute__ ((packed))
+#else
+#error "Unsupported compiler?"
+#endif
+
+#ifndef __WBGEN2_MACROS_DEFINED__
+#define __WBGEN2_MACROS_DEFINED__
+#define WBGEN2_GEN_MASK(offset, size) (((1<<(size))-1) << (offset))
+#define WBGEN2_GEN_WRITE(value, offset, size) (((value) & ((1<<(size))-1)) << (offset))
+#define WBGEN2_GEN_READ(reg, offset, size) (((reg) >> (offset)) & ((1<<(size))-1))
+#define WBGEN2_SIGN_EXTEND(value, bits) (((value) & (1<<bits) ? ~((1<<(bits))-1): 0 ) | (value))
+#endif
+
+
+/* definitions for register: VIC Control Register */
+
+/* definitions for field: VIC Enable in reg: VIC Control Register */
+#define VIC_CTL_ENABLE WBGEN2_GEN_MASK(0, 1)
+
+/* definitions for field: VIC output polarity in reg: VIC Control Register */
+#define VIC_CTL_POL WBGEN2_GEN_MASK(1, 1)
+
+/* definitions for field: Emulate Edge sensitive output in reg: VIC Control Register */
+#define VIC_CTL_EMU_EDGE WBGEN2_GEN_MASK(2, 1)
+
+/* definitions for field: Emulated Edge pulse timer in reg: VIC Control Register */
+#define VIC_CTL_EMU_LEN_MASK WBGEN2_GEN_MASK(3, 16)
+#define VIC_CTL_EMU_LEN_SHIFT 3
+#define VIC_CTL_EMU_LEN_W(value) WBGEN2_GEN_WRITE(value, 3, 16)
+#define VIC_CTL_EMU_LEN_R(reg) WBGEN2_GEN_READ(reg, 3, 16)
+
+/* definitions for register: Raw Interrupt Status Register */
+
+/* definitions for register: Interrupt Enable Register */
+
+/* definitions for register: Interrupt Disable Register */
+
+/* definitions for register: Interrupt Mask Register */
+
+/* definitions for register: Vector Address Register */
+
+/* definitions for register: Software Interrupt Register */
+
+/* definitions for register: End Of Interrupt Acknowledge Register */
+/* definitions for RAM: Interrupt Vector Table */
+#define VIC_IVT_RAM_BYTES 0x00000080 /* size in bytes */
+#define VIC_IVT_RAM_WORDS 0x00000020 /* size in 32-bit words, 32-bit aligned */
+#define VIC_IVT_RAM_BASE 0x00000080
+
+/* [0x0]: REG VIC Control Register */
+#define VIC_REG_CTL 0x00000000
+/* [0x4]: REG Raw Interrupt Status Register */
+#define VIC_REG_RISR 0x00000004
+/* [0x8]: REG Interrupt Enable Register */
+#define VIC_REG_IER 0x00000008
+/* [0xc]: REG Interrupt Disable Register */
+#define VIC_REG_IDR 0x0000000c
+/* [0x10]: REG Interrupt Mask Register */
+#define VIC_REG_IMR 0x00000010
+/* [0x14]: REG Vector Address Register */
+#define VIC_REG_VAR 0x00000014
+/* [0x18]: REG Software Interrupt Register */
+#define VIC_REG_SWIR 0x00000018
+/* [0x1c]: REG End Of Interrupt Acknowledge Register */
+#define VIC_REG_EOIR 0x0000001c
+
+
+#endif
diff --git a/kernel/spec-fmc.c b/kernel/spec-fmc.c
index 5e56c5d..83138bb 100644
--- a/kernel/spec-fmc.c
+++ b/kernel/spec-fmc.c
@@ -93,14 +93,15 @@ out:
return ret;
}
-static int spec_irq_request(struct fmc_device *fmc, irq_handler_t handler,
- char *name, int flags)
+/* Low-level IRQ request function: set up handler, with or without the VIC */
+static int spec_shared_irq_request(struct fmc_device *fmc,
+ irq_handler_t handler, char *name, int flags)
{
struct spec_dev *spec = fmc->carrier_data;
int ret;
u32 value;
- ret = request_irq(fmc->irq, handler, flags, name, fmc);
+ ret = request_irq(spec->pdev->irq, handler, flags, name, fmc);
if (ret)
return ret;
@@ -118,7 +119,67 @@ static int spec_irq_request(struct fmc_device *fmc, irq_handler_t handler,
return 0;
}
-static void spec_irq_ack(struct fmc_device *fmc)
+static void spec_shared_irq_ack(struct fmc_device *fmc);
+
+static irqreturn_t spec_vic_irq_handler(int id, void *data)
+{
+ struct fmc_device *fmc = (struct fmc_device *)data;
+ irqreturn_t rv;
+
+ rv = spec_vic_irq_dispatch((struct spec_dev *)fmc->carrier_data);
+
+ spec_shared_irq_ack(fmc);
+ return IRQ_HANDLED;
+}
+
+static struct fmc_gpio spec_vic_gpio_cfg[] = {
+ {
+ .gpio = FMC_GPIO_IRQ(1),
+ .mode = GPIOF_DIR_IN,
+ .irqmode = IRQF_TRIGGER_RISING,
+ }
+};
+
+static int spec_irq_request(struct fmc_device *fmc, irq_handler_t handler,
+ char *name, int flags)
+{
+ struct spec_dev *spec = fmc->carrier_data;
+ int rv;
+
+ /* VIC mode interrupt */
+ if (!(flags & IRQF_SHARED)) {
+ int first_time = !spec->vic;
+
+ /* configure the VIC */
+ rv = spec_vic_irq_request(spec, fmc, fmc->irq, handler);
+
+ if (rv)
+ return rv;
+
+ /* on first IRQ, configure VIC "master" handler and GPIO too */
+ if (first_time) {
+ rv = spec_shared_irq_request(fmc, spec_vic_irq_handler,
+ "spec-vic", IRQF_SHARED);
+ if (rv)
+ return rv;
+
+ fmc->op->gpio_config(fmc, spec_vic_gpio_cfg,
+ ARRAY_SIZE(spec_vic_gpio_cfg));
+ }
+
+ } else {
+ rv = spec_shared_irq_request(fmc, handler, name, flags);
+ printk("Requesting irq '%s' in shared mode (rv %d)\n", name,
+ rv);
+ }
+
+ if (!rv)
+ spec->flags |= SPEC_FLAG_IRQS_REQUESTED;
+
+ return rv;
+}
+
+static void spec_shared_irq_ack(struct fmc_device *fmc)
{
struct spec_dev *spec = fmc->carrier_data;
@@ -130,15 +191,35 @@ static void spec_irq_ack(struct fmc_device *fmc)
gennum_readl(spec, GNGPIO_INT_STATUS);
}
-static int spec_irq_free(struct fmc_device *fmc)
+static void spec_irq_ack(struct fmc_device *fmc)
{
struct spec_dev *spec = fmc->carrier_data;
- gennum_writel(spec, 0xffff, GNGPIO_INT_MASK_SET); /* disable */
- free_irq(fmc->irq, fmc);
+ if (!spec->vic)
+ spec_shared_irq_ack(fmc);
+
+ /* Nothing for VIC here, all irqs are acked by master VIC handler */
+}
+
+static int spec_shared_irq_free(struct fmc_device *fmc)
+{
+ struct spec_dev *spec = fmc->carrier_data;
+
+ gennum_writel(spec, 0xffff, GNGPIO_INT_MASK_SET); /* disable */
+ free_irq(spec->pdev->irq, fmc);
return 0;
}
+static int spec_irq_free(struct fmc_device *fmc)
+{
+ struct spec_dev *spec = fmc->carrier_data;
+
+ if (spec->vic)
+ return spec_vic_irq_free(spec, spec->pdev->irq);
+ else
+ return spec_shared_irq_free(fmc);
+}
+
/* This is the mapping from virtual GPIO pin numbers to raw gpio numbers */
struct {
int virtual; int raw;
@@ -230,8 +311,7 @@ static int spec_gpio_config(struct fmc_device *fmc, struct fmc_gpio *gpio,
if (gpio->carrier_name) {
/* so, it's ours */
gpio->_gpio = gpio->gpio;
- }
- else if (!gpio->_gpio) {
+ } else if (!gpio->_gpio) {
/* virtual but not mapped (or poor gpio0) */
i = spec_map_pin(gpio->gpio);
if (i < 0)
@@ -360,6 +440,13 @@ static void spec_irq_exit(struct fmc_device *fmc)
for (i = 0; i < 7; i++)
gennum_writel(spec, 0, GNINT_CFG(i));
fmc->op->irq_ack(fmc); /* just to be safe */
+
+ /* VIC mode: release VIC resources and disable VIC master IRQ line */
+ if (spec->vic) {
+ spec_vic_cleanup(spec);
+ gennum_writel(spec, 0xffff, GNGPIO_INT_MASK_SET); /* disable */
+ free_irq(spec->pdev->irq, fmc);
+ }
}
static int check_golden(struct fmc_device *fmc)
@@ -392,7 +479,7 @@ static int check_golden(struct fmc_device *fmc)
int spec_fmc_create(struct spec_dev *spec)
{
struct fmc_device *fmc;
- struct pci_dev *pdev;
+ struct pci_dev *pdev;
int ret;
fmc = kzalloc(sizeof(*fmc), GFP_KERNEL);
@@ -408,7 +495,6 @@ int spec_fmc_create(struct spec_dev *spec)
fmc->fpga_base = spec->remap[0];
fmc->memlen = 1 << 20;
- fmc->irq = spec->pdev->irq;
fmc->op = &spec_fmc_operations;
fmc->hwdev = &spec->pdev->dev; /* for messages */
spec->fmc = fmc;
diff --git a/kernel/spec-vic.c b/kernel/spec-vic.c
new file mode 100644
index 0000000..ba0bfee
--- /dev/null
+++ b/kernel/spec-vic.c
@@ -0,0 +1,200 @@
+/*
+* Copyright (C) 2013 CERN (www.cern.ch)
+* Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
+*
+* Released according to the GNU GPL, version 2 or any later version
+*
+* Driver for SPEC (Simple PCI Express FMC carrier) board.
+* VIC (Vectored Interrupt Controller) support code.
+*/
+
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/fmc.h>
+#include <linux/fmc-sdb.h>
+
+#include "spec.h"
+
+#include "hw/vic_regs.h"
+
+#define VIC_MAX_VECTORS 32
+
+#define VIC_SDB_VENDOR 0xce42
+#define VIC_SDB_DEVICE 0x0013
+
+/* A Vectored Interrupt Controller object */
+struct vic_irq_controller {
+ /* already-initialized flag */
+ int initialized;
+ /* Base address (FPGA-relative) */
+ uint32_t base;
+ /* Mapped base address of the VIC */
+ void *kernel_va;
+
+ /* Vector table */
+ struct vector {
+ /* Saved ID of the vector (for autodetection purposes) */
+ int saved_id;
+ /* Pointer to the assigned handler */
+ irq_handler_t handler;
+ /* FMC device that owns the interrupt */
+ struct fmc_device *requestor;
+ } vectors[VIC_MAX_VECTORS];
+};
+
+static inline void vic_writel(struct vic_irq_controller *vic, uint32_t value,
+ uint32_t offset)
+{
+ writel(value, vic->kernel_va + offset);
+}
+
+static inline uint32_t vic_readl(struct vic_irq_controller *vic,
+ uint32_t offset)
+{
+ return readl(vic->kernel_va + offset);
+}
+
+static int spec_vic_init(struct spec_dev *spec, struct fmc_device *fmc)
+{
+ int i;
+ signed long vic_base;
+ struct vic_irq_controller *vic;
+
+ /*
+ * Try to look up the VIC in the SDB tree - note that IRQs
+ * shall be requested after the FMC driver has scanned the SDB tree
+ */
+ vic_base =
+ fmc_find_sdb_device(fmc->sdb, VIC_SDB_VENDOR, VIC_SDB_DEVICE, NULL);
+
+ if (vic_base < 0) {
+ dev_err(&spec->pdev->dev,
+ "VIC controller not found, but a VIC interrupt requested. Wrong gateware?\n");
+ return -ENODEV;
+ }
+
+ dev_info(&spec->pdev->dev, "Found VIC @ 0x%lx\n", vic_base);
+
+ vic = kzalloc(sizeof(struct vic_irq_controller), GFP_KERNEL);
+ if (!vic)
+ return -ENOMEM;
+
+ vic->kernel_va = spec->remap[0] + vic_base;
+ vic->base = (uint32_t) vic_base;
+
+ /* disable all IRQs, copy the vector table with pre-defined IRQ ids */
+ vic_writel(vic, 0xffffffff, VIC_REG_IDR);
+ for (i = 0; i < VIC_MAX_VECTORS; i++)
+ vic->vectors[i].saved_id =
+ vic_readl(vic, VIC_IVT_RAM_BASE + 4 * i);
+
+ /* config the VIC output: active high, edge, width = 256 tick (4 us) */
+ vic_writel(vic,
+ VIC_CTL_ENABLE | VIC_CTL_POL | VIC_CTL_EMU_EDGE |
+ VIC_CTL_EMU_LEN_W(250), VIC_REG_CTL);
+
+ vic->initialized = 1;
+ spec->vic = vic;
+
+ return 0;
+}
+
+void spec_vic_cleanup(struct spec_dev *spec)
+{
+ if (!spec->vic)
+ return;
+
+ /* Disable all irq lines and the VIC in general */
+ vic_writel(spec->vic, 0xffffffff, VIC_REG_IDR);
+ vic_writel(spec->vic, 0, VIC_REG_CTL);
+ kfree(spec->vic);
+ spec->vic = NULL;
+}
+
+irqreturn_t spec_vic_irq_dispatch(struct spec_dev *spec)
+{
+ struct vic_irq_controller *vic = spec->vic;
+ int index, rv;
+ struct vector *vec;
+
+ /*
+ * Our parent IRQ handler: read the index value
+ * from the Vector Address Register, and find matching handler
+ */
+ index = vic_readl(vic, VIC_REG_VAR) & 0xff;
+
+ if (index >= VIC_MAX_VECTORS)
+ goto fail;
+
+ vec = &vic->vectors[index];
+ if (!vec->handler)
+ goto fail;
+
+ rv = vec->handler(vec->saved_id, vec->requestor);
+
+ vic_writel(vic, 0, VIC_REG_EOIR); /* ack the irq */
+ return rv;
+
+fail:
+ return 0;
+}
+
+int spec_vic_irq_request(struct spec_dev *spec, struct fmc_device *fmc,
+ unsigned long id, irq_handler_t handler)
+{
+ struct vic_irq_controller *vic;
+ int rv = 0, i;
+
+ /* First interrupt to be requested? Look up and init the VIC */
+ if (!spec->vic) {
+ rv = spec_vic_init(spec, fmc);
+ if (rv)
+ return rv;
+ }
+
+ vic = spec->vic;
+
+ for (i = 0; i < VIC_MAX_VECTORS; i++) {
+ /* find vector in stored table, assign handle, enable */
+ if (vic->vectors[i].saved_id == id) {
+ spin_lock(&spec->irq_lock);
+
+ vic_writel(vic, i, VIC_IVT_RAM_BASE + 4 * i);
+ vic->vectors[i].requestor = fmc;
+ vic->vectors[i].handler = handler;
+ vic_writel(vic, (1 << i), VIC_REG_IER);
+
+ spin_unlock(&spec->irq_lock);
+ return 0;
+ }
+ }
+
+
+ return -EINVAL;
+
+}
+
+int spec_vic_irq_free(struct spec_dev *spec, unsigned long id)
+{
+ int i;
+
+ for (i = 0; i < VIC_MAX_VECTORS; i++) {
+ uint32_t vec = spec->vic->vectors[i].saved_id;
+ if (vec == id) {
+ spin_lock(&spec->irq_lock);
+
+ vic_writel(spec->vic, 1 << i, VIC_REG_IDR);
+ vic_writel(spec->vic, vec, VIC_IVT_RAM_BASE + 4 * i);
+ spec->vic->vectors[i].handler = NULL;
+
+ spin_unlock(&spec->irq_lock);
+ }
+ }
+
+ return 0;
+}
+
+void spec_vic_irq_ack(struct spec_dev *spec, unsigned long id)
+{
+ /* fixme: do we need anything special here? */
+}
diff --git a/kernel/spec.h b/kernel/spec.h
index fe8cfa0..3e3d7d7 100644
--- a/kernel/spec.h
+++ b/kernel/spec.h
@@ -33,9 +33,12 @@ struct spec_dev {
int irq_count; /* for mezzanine use too */
struct completion compl;
struct gpio_chip *gpio;
+ struct vic_irq_controller *vic;
+ spinlock_t irq_lock;
};
#define SPEC_FLAG_FAKE_EEPROM 0x00000001
+#define SPEC_FLAG_IRQS_REQUESTED 0x00000002
/* Registers for GN4124 access */
enum {
@@ -141,5 +144,11 @@ extern int spec_eeprom_write(struct fmc_device *fmc, uint32_t offset,
extern int spec_gpio_init(struct fmc_device *fmc);
extern void spec_gpio_exit(struct fmc_device *fmc);
+int spec_vic_irq_request(struct spec_dev *spec, struct fmc_device *fmc,
+ unsigned long id, irq_handler_t handler);
+
+int spec_vic_irq_free(struct spec_dev *spec, unsigned long id);
+irqreturn_t spec_vic_irq_dispatch(struct spec_dev *spec);
+void spec_vic_cleanup(struct spec_dev *spec);
#endif /* __SPEC_H__ */
--
GitLab