[PATCH v4] plat-versatile: modernize FPGA IRQ controller
Linus Walleij
linus.walleij at linaro.org
Tue Apr 17 15:24:07 EDT 2012
This does two things to the FPGA IRQ controller in the versatile
family:
- Convert to MULTI_IRQ_HANDLER so we can drop the entry macro
from the Integrator. The C IRQ handler was inspired from
arch/arm/common/vic.c, recent bug discovered in this handler was
accounted for.
- Convert to using IRQ domains so we can get rid of the NO_IRQ
mess and proceed with device tree and such stuff.
As part of the exercise, bump all the low IRQ numbers on the
Integrator PIC to start from 1 rather than 0, since IRQ 0 is
now NO_IRQ. The Linux IRQ numbers are thus entirely decoupled
from the hardware IRQ numbers in this controller.
I was unable to split this patch. The main reason is the half-done
conversion to device tree in Versatile.
Tested on Integrator/AP and Integrator/CP.
Cc: Rob Herring <rob.herring at calxeda.com>
Cc: Grant Likely <grant.likely at secretlab.ca>
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
ChangeLog v3->v4:
- Get rid of the awkward host_data solution, Rob told me how
to do it.
ChangeLog v2->v3:
- After som hints from Rob Herring and meditating about the
mapping function I figured out how to do the mapping properly.
- Introduce a custom mapping function that will skip over the
holes in the valid map.
- No need to bump the platform NR_IRQS since we handle holes in
the map gracefully.
- Renumbered the Integrator PIC IRQs to avoid using IRQ 0 which
is now invalid.
- Redefined IRQ_PIC_END to the last used PIC IRQ in analogy
with the other IRQ numbers. The previous definition was the
last HW IRQ number on the PIC and this is no longer relevant.
- Use a file-local pointer to pass the pointer to the handler
data to the mapping function, the alternative is to modify
the mapping functions to take an opaque parameter as well.
- Number Integrator/AP IRQs starting from IRQ_PIC_START as
well, not 0 as before.
ChangeLog v1->v2:
- Drop the patch messing with the masks in prev [1/3] patch.
- Squash the movement of the main struct, it I can split it out
again if desired.
- Fix the entry-level handler to account for the bug recently
discovered in the VIC code and thus avoid to bring that over
to this driver as well.
- Extend the number of IRQs on each platform to account for
the "no holes" problem mentioned in the commit info.
- Introduce a cic_mask variable to make Integrator/CP
IRQ setup it a little more readable.
- Drop excess paretheses in mask/unmask
- Fix typos, edit commit message.
---
arch/arm/Kconfig | 1 +
.../arm/mach-integrator/include/mach/entry-macro.S | 39 -------
arch/arm/mach-integrator/include/mach/irqs.h | 63 +++++------
arch/arm/mach-integrator/integrator_ap.c | 10 +-
arch/arm/mach-integrator/integrator_cp.c | 33 ++----
arch/arm/mach-versatile/core.c | 13 +--
arch/arm/plat-versatile/Kconfig | 6 +
arch/arm/plat-versatile/fpga-irq.c | 116 +++++++++++++++++---
arch/arm/plat-versatile/include/plat/fpga-irq.h | 11 +-
9 files changed, 162 insertions(+), 130 deletions(-)
delete mode 100644 arch/arm/mach-integrator/include/mach/entry-macro.S
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index cf006d4..2f67f6c 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -280,6 +280,7 @@ config ARCH_INTEGRATOR
select NEED_MACH_IO_H
select NEED_MACH_MEMORY_H
select SPARSE_IRQ
+ select MULTI_IRQ_HANDLER
help
Support for ARM's Integrator platform.
diff --git a/arch/arm/mach-integrator/include/mach/entry-macro.S b/arch/arm/mach-integrator/include/mach/entry-macro.S
deleted file mode 100644
index 5cc7b85..0000000
--- a/arch/arm/mach-integrator/include/mach/entry-macro.S
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * arch/arm/mach-integrator/include/mach/entry-macro.S
- *
- * Low-level IRQ helper macros for Integrator platforms
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- */
-#include <mach/hardware.h>
-#include <mach/platform.h>
-#include <mach/irqs.h>
-
- .macro get_irqnr_preamble, base, tmp
- .endm
-
- .macro get_irqnr_and_base, irqnr, irqstat, base, tmp
-/* FIXME: should not be using soo many LDRs here */
- ldr \base, =IO_ADDRESS(INTEGRATOR_IC_BASE)
- mov \irqnr, #IRQ_PIC_START
- ldr \irqstat, [\base, #IRQ_STATUS] @ get masked status
- ldr \base, =IO_ADDRESS(INTEGRATOR_HDR_BASE)
- teq \irqstat, #0
- ldreq \irqstat, [\base, #(INTEGRATOR_HDR_IC_OFFSET+IRQ_STATUS)]
- moveq \irqnr, #IRQ_CIC_START
-
-1001: tst \irqstat, #15
- bne 1002f
- add \irqnr, \irqnr, #4
- movs \irqstat, \irqstat, lsr #4
- bne 1001b
-1002: tst \irqstat, #1
- bne 1003f
- add \irqnr, \irqnr, #1
- movs \irqstat, \irqstat, lsr #1
- bne 1002b
-1003: /* EQ will be set if no irqs pending */
- .endm
-
diff --git a/arch/arm/mach-integrator/include/mach/irqs.h b/arch/arm/mach-integrator/include/mach/irqs.h
index a19a1a2..7371018 100644
--- a/arch/arm/mach-integrator/include/mach/irqs.h
+++ b/arch/arm/mach-integrator/include/mach/irqs.h
@@ -22,37 +22,37 @@
/*
* Interrupt numbers
*/
-#define IRQ_PIC_START 0
-#define IRQ_SOFTINT 0
-#define IRQ_UARTINT0 1
-#define IRQ_UARTINT1 2
-#define IRQ_KMIINT0 3
-#define IRQ_KMIINT1 4
-#define IRQ_TIMERINT0 5
-#define IRQ_TIMERINT1 6
-#define IRQ_TIMERINT2 7
-#define IRQ_RTCINT 8
-#define IRQ_AP_EXPINT0 9
-#define IRQ_AP_EXPINT1 10
-#define IRQ_AP_EXPINT2 11
-#define IRQ_AP_EXPINT3 12
-#define IRQ_AP_PCIINT0 13
-#define IRQ_AP_PCIINT1 14
-#define IRQ_AP_PCIINT2 15
-#define IRQ_AP_PCIINT3 16
-#define IRQ_AP_V3INT 17
-#define IRQ_AP_CPINT0 18
-#define IRQ_AP_CPINT1 19
-#define IRQ_AP_LBUSTIMEOUT 20
-#define IRQ_AP_APCINT 21
-#define IRQ_CP_CLCDCINT 22
-#define IRQ_CP_MMCIINT0 23
-#define IRQ_CP_MMCIINT1 24
-#define IRQ_CP_AACIINT 25
-#define IRQ_CP_CPPLDINT 26
-#define IRQ_CP_ETHINT 27
-#define IRQ_CP_TSPENINT 28
-#define IRQ_PIC_END 31
+#define IRQ_PIC_START 1
+#define IRQ_SOFTINT 1
+#define IRQ_UARTINT0 2
+#define IRQ_UARTINT1 3
+#define IRQ_KMIINT0 4
+#define IRQ_KMIINT1 5
+#define IRQ_TIMERINT0 6
+#define IRQ_TIMERINT1 7
+#define IRQ_TIMERINT2 8
+#define IRQ_RTCINT 9
+#define IRQ_AP_EXPINT0 10
+#define IRQ_AP_EXPINT1 11
+#define IRQ_AP_EXPINT2 12
+#define IRQ_AP_EXPINT3 13
+#define IRQ_AP_PCIINT0 14
+#define IRQ_AP_PCIINT1 15
+#define IRQ_AP_PCIINT2 16
+#define IRQ_AP_PCIINT3 17
+#define IRQ_AP_V3INT 18
+#define IRQ_AP_CPINT0 19
+#define IRQ_AP_CPINT1 20
+#define IRQ_AP_LBUSTIMEOUT 21
+#define IRQ_AP_APCINT 22
+#define IRQ_CP_CLCDCINT 23
+#define IRQ_CP_MMCIINT0 24
+#define IRQ_CP_MMCIINT1 25
+#define IRQ_CP_AACIINT 26
+#define IRQ_CP_CPPLDINT 27
+#define IRQ_CP_ETHINT 28
+#define IRQ_CP_TSPENINT 29
+#define IRQ_PIC_END 29
#define IRQ_CIC_START 32
#define IRQ_CM_SOFTINT 32
@@ -80,4 +80,3 @@
#define NR_IRQS_INTEGRATOR_AP 34
#define NR_IRQS_INTEGRATOR_CP 47
-
diff --git a/arch/arm/mach-integrator/integrator_ap.c b/arch/arm/mach-integrator/integrator_ap.c
index 871f148..c857501 100644
--- a/arch/arm/mach-integrator/integrator_ap.c
+++ b/arch/arm/mach-integrator/integrator_ap.c
@@ -162,12 +162,6 @@ static void __init ap_map_io(void)
#define INTEGRATOR_SC_VALID_INT 0x003fffff
-static struct fpga_irq_data sc_irq_data = {
- .base = VA_IC_BASE,
- .irq_start = 0,
- .chip.name = "SC",
-};
-
static void __init ap_init_irq(void)
{
/* Disable all interrupts initially. */
@@ -178,7 +172,8 @@ static void __init ap_init_irq(void)
writel(-1, VA_IC_BASE + IRQ_ENABLE_CLEAR);
writel(-1, VA_IC_BASE + FIQ_ENABLE_CLEAR);
- fpga_irq_init(-1, INTEGRATOR_SC_VALID_INT, &sc_irq_data);
+ fpga_irq_init(VA_IC_BASE, "SC", IRQ_PIC_START,
+ -1, INTEGRATOR_SC_VALID_INT, NULL);
}
#ifdef CONFIG_PM
@@ -478,6 +473,7 @@ MACHINE_START(INTEGRATOR, "ARM-Integrator")
.nr_irqs = NR_IRQS_INTEGRATOR_AP,
.init_early = integrator_init_early,
.init_irq = ap_init_irq,
+ .handle_irq = fpga_handle_irq,
.timer = &ap_timer,
.init_machine = ap_init,
.restart = integrator_restart,
diff --git a/arch/arm/mach-integrator/integrator_cp.c b/arch/arm/mach-integrator/integrator_cp.c
index 48a115a..a56c536 100644
--- a/arch/arm/mach-integrator/integrator_cp.c
+++ b/arch/arm/mach-integrator/integrator_cp.c
@@ -143,30 +143,14 @@ static void __init intcp_map_io(void)
iotable_init(intcp_io_desc, ARRAY_SIZE(intcp_io_desc));
}
-static struct fpga_irq_data cic_irq_data = {
- .base = INTCP_VA_CIC_BASE,
- .irq_start = IRQ_CIC_START,
- .chip.name = "CIC",
-};
-
-static struct fpga_irq_data pic_irq_data = {
- .base = INTCP_VA_PIC_BASE,
- .irq_start = IRQ_PIC_START,
- .chip.name = "PIC",
-};
-
-static struct fpga_irq_data sic_irq_data = {
- .base = INTCP_VA_SIC_BASE,
- .irq_start = IRQ_SIC_START,
- .chip.name = "SIC",
-};
-
static void __init intcp_init_irq(void)
{
- u32 pic_mask, sic_mask;
+ u32 pic_mask, cic_mask, sic_mask;
+ /* These masks are for the HW IRQ registers */
pic_mask = ~((~0u) << (11 - IRQ_PIC_START));
pic_mask |= (~((~0u) << (29 - 22))) << 22;
+ cic_mask = ~((~0u) << (1 + IRQ_CIC_END - IRQ_CIC_START));
sic_mask = ~((~0u) << (1 + IRQ_SIC_END - IRQ_SIC_START));
/*
@@ -179,12 +163,14 @@ static void __init intcp_init_irq(void)
writel(sic_mask, INTCP_VA_SIC_BASE + IRQ_ENABLE_CLEAR);
writel(sic_mask, INTCP_VA_SIC_BASE + FIQ_ENABLE_CLEAR);
- fpga_irq_init(-1, pic_mask, &pic_irq_data);
+ fpga_irq_init(INTCP_VA_PIC_BASE, "PIC", IRQ_PIC_START,
+ -1, pic_mask, NULL);
- fpga_irq_init(-1, ~((~0u) << (1 + IRQ_CIC_END - IRQ_CIC_START)),
- &cic_irq_data);
+ fpga_irq_init(INTCP_VA_CIC_BASE, "CIC", IRQ_CIC_START,
+ -1, cic_mask, NULL);
- fpga_irq_init(IRQ_CP_CPPLDINT, sic_mask, &sic_irq_data);
+ fpga_irq_init(INTCP_VA_SIC_BASE, "SIC", IRQ_SIC_START,
+ IRQ_CP_CPPLDINT, sic_mask, NULL);
}
/*
@@ -467,6 +453,7 @@ MACHINE_START(CINTEGRATOR, "ARM-IntegratorCP")
.nr_irqs = NR_IRQS_INTEGRATOR_CP,
.init_early = intcp_init_early,
.init_irq = intcp_init_irq,
+ .handle_irq = fpga_handle_irq,
.timer = &cp_timer,
.init_machine = intcp_init,
.restart = integrator_restart,
diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c
index 6bbd74e..6f5fb46 100644
--- a/arch/arm/mach-versatile/core.c
+++ b/arch/arm/mach-versatile/core.c
@@ -66,12 +66,6 @@
#define VA_VIC_BASE __io_address(VERSATILE_VIC_BASE)
#define VA_SIC_BASE __io_address(VERSATILE_SIC_BASE)
-static struct fpga_irq_data sic_irq = {
- .base = VA_SIC_BASE,
- .irq_start = IRQ_SIC_START,
- .chip.name = "SIC",
-};
-
#if 1
#define IRQ_MMCI0A IRQ_VICSOURCE22
#define IRQ_AACI IRQ_VICSOURCE24
@@ -105,8 +99,11 @@ void __init versatile_init_irq(void)
writel(~0, VA_SIC_BASE + SIC_IRQ_ENABLE_CLEAR);
- fpga_irq_init(IRQ_VICSOURCE31, ~PIC_MASK, &sic_irq);
- irq_domain_generate_simple(sic_of_match, VERSATILE_SIC_BASE, IRQ_SIC_START);
+ np = of_find_matching_node_by_address(NULL, sic_of_match,
+ VERSATILE_SIC_BASE);
+
+ fpga_irq_init(VA_SIC_BASE, "SIC", IRQ_SIC_START,
+ IRQ_VICSOURCE31, ~PIC_MASK, np);
/*
* Interrupts on secondary controller from 0 to 8 are routed to
diff --git a/arch/arm/plat-versatile/Kconfig b/arch/arm/plat-versatile/Kconfig
index 043f7b0..81ee7cc 100644
--- a/arch/arm/plat-versatile/Kconfig
+++ b/arch/arm/plat-versatile/Kconfig
@@ -5,6 +5,12 @@ config PLAT_VERSATILE_CLCD
config PLAT_VERSATILE_FPGA_IRQ
bool
+ select IRQ_DOMAIN
+
+config PLAT_VERSATILE_FPGA_IRQ_NR
+ int
+ default 4
+ depends on PLAT_VERSATILE_FPGA_IRQ
config PLAT_VERSATILE_LEDS
def_bool y if LEDS_CLASS
diff --git a/arch/arm/plat-versatile/fpga-irq.c b/arch/arm/plat-versatile/fpga-irq.c
index f0cc8e1..6e70d03 100644
--- a/arch/arm/plat-versatile/fpga-irq.c
+++ b/arch/arm/plat-versatile/fpga-irq.c
@@ -3,7 +3,10 @@
*/
#include <linux/irq.h>
#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <asm/exception.h>
#include <asm/mach/irq.h>
#include <plat/fpga-irq.h>
@@ -12,10 +15,32 @@
#define IRQ_ENABLE_SET 0x08
#define IRQ_ENABLE_CLEAR 0x0c
+/**
+ * struct fpga_irq_data - irq data container for the FPGA IRQ controller
+ * @base: memory offset in virtual memory
+ * @irq_start: first IRQ number handled by this instance
+ * @chip: chip container for this instance
+ * @domain: IRQ domain for this instance
+ * @valid: mask for valid IRQs on this controller
+ * @used_irqs: number of active IRQs on this controller
+ */
+struct fpga_irq_data {
+ void __iomem *base;
+ unsigned int irq_start;
+ struct irq_chip chip;
+ u32 valid;
+ struct irq_domain *domain;
+ u8 used_irqs;
+};
+
+/* we cannot allocate memory when the controllers are initially registered */
+static struct fpga_irq_data fpga_irq_devices[CONFIG_PLAT_VERSATILE_FPGA_IRQ_NR];
+static int fpga_irq_id;
+
static void fpga_irq_mask(struct irq_data *d)
{
struct fpga_irq_data *f = irq_data_get_irq_chip_data(d);
- u32 mask = 1 << (d->irq - f->irq_start);
+ u32 mask = 1 << d->hwirq;
writel(mask, f->base + IRQ_ENABLE_CLEAR);
}
@@ -23,7 +48,7 @@ static void fpga_irq_mask(struct irq_data *d)
static void fpga_irq_unmask(struct irq_data *d)
{
struct fpga_irq_data *f = irq_data_get_irq_chip_data(d);
- u32 mask = 1 << (d->irq - f->irq_start);
+ u32 mask = 1 << d->hwirq;
writel(mask, f->base + IRQ_ENABLE_SET);
}
@@ -41,32 +66,93 @@ static void fpga_irq_handle(unsigned int irq, struct irq_desc *desc)
do {
irq = ffs(status) - 1;
status &= ~(1 << irq);
-
- generic_handle_irq(irq + f->irq_start);
+ generic_handle_irq(irq_find_mapping(f->domain, irq));
} while (status);
}
-void __init fpga_irq_init(int parent_irq, u32 valid, struct fpga_irq_data *f)
+/*
+ * Handle each interrupt in a single FPGA IRQ controller. Returns non-zero
+ * if we've handled at least one interrupt. This does a single read of the
+ * status register and handles all interrupts in order from LSB first.
+ */
+static int handle_one_fpga(struct fpga_irq_data *f, struct pt_regs *regs)
+{
+ int handled = 0;
+ int irq;
+ u32 status;
+
+ while ((status = readl(f->base + IRQ_STATUS))) {
+ irq = ffs(status) - 1;
+ handle_IRQ(irq_find_mapping(f->domain, irq), regs);
+ handled = 1;
+ }
+
+ return handled;
+}
+
+/*
+ * Keep iterating over all registered FPGA IRQ controllers until there are
+ * no pending interrupts.
+ */
+asmlinkage void __exception_irq_entry fpga_handle_irq(struct pt_regs *regs)
{
- unsigned int i;
+ int i, handled;
+ do {
+ for (i = 0, handled = 0; i < fpga_irq_id; ++i)
+ handled |= handle_one_fpga(&fpga_irq_devices[i], regs);
+ } while (handled);
+}
+
+static int fpga_irqdomain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ struct fpga_irq_data *f = d->host_data;
+
+ /* Skip invalid IRQs, only register handlers for the real ones */
+ if (!(f->valid & (1 << hwirq)))
+ return -ENOTSUPP;
+ irq_set_chip_data(irq, f);
+ irq_set_chip_and_handler(irq, &f->chip,
+ handle_level_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ f->used_irqs++;
+ return 0;
+}
+
+static struct irq_domain_ops fpga_irqdomain_ops = {
+ .map = fpga_irqdomain_map,
+ .xlate = irq_domain_xlate_onetwocell,
+};
+
+void __init fpga_irq_init(void __iomem *base, const char *name, int irq_start,
+ int parent_irq, u32 valid, struct device_node *node)
+{
+ struct fpga_irq_data *f;
+
+ if (fpga_irq_id >= ARRAY_SIZE(fpga_irq_devices)) {
+ printk(KERN_ERR "%s: too few FPGA IRQ controllers, increase CONFIG_PLAT_VERSATILE_FPGA_IRQ_NR\n", __func__);
+ return;
+ }
+
+ f = &fpga_irq_devices[fpga_irq_id];
+ f->base = base;
+ f->irq_start = irq_start;
+ f->chip.name = name;
f->chip.irq_ack = fpga_irq_mask;
f->chip.irq_mask = fpga_irq_mask;
f->chip.irq_unmask = fpga_irq_unmask;
+ f->valid = valid;
if (parent_irq != -1) {
irq_set_handler_data(parent_irq, f);
irq_set_chained_handler(parent_irq, fpga_irq_handle);
}
- for (i = 0; i < 32; i++) {
- if (valid & (1 << i)) {
- unsigned int irq = f->irq_start + i;
+ f->domain = irq_domain_add_legacy(node, fls(valid), f->irq_start, 0,
+ &fpga_irqdomain_ops, f);
+ pr_info("FPGA IRQ chip %d \"%s\" @ %p, %u irqs\n",
+ fpga_irq_id, name, base, f->used_irqs);
- irq_set_chip_data(irq, f);
- irq_set_chip_and_handler(irq, &f->chip,
- handle_level_irq);
- set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
- }
- }
+ fpga_irq_id++;
}
diff --git a/arch/arm/plat-versatile/include/plat/fpga-irq.h b/arch/arm/plat-versatile/include/plat/fpga-irq.h
index 627fafd..91bcfb6 100644
--- a/arch/arm/plat-versatile/include/plat/fpga-irq.h
+++ b/arch/arm/plat-versatile/include/plat/fpga-irq.h
@@ -1,12 +1,11 @@
#ifndef PLAT_FPGA_IRQ_H
#define PLAT_FPGA_IRQ_H
-struct fpga_irq_data {
- void __iomem *base;
- unsigned int irq_start;
- struct irq_chip chip;
-};
+struct device_node;
+struct pt_regs;
-void fpga_irq_init(int, u32, struct fpga_irq_data *);
+void fpga_handle_irq(struct pt_regs *regs);
+void fpga_irq_init(void __iomem *, const char *, int, int, u32,
+ struct device_node *node);
#endif
--
1.7.7.6
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