Index: head/sys/riscv/riscv/plic.c
===================================================================
--- head/sys/riscv/riscv/plic.c (revision 354716)
+++ head/sys/riscv/riscv/plic.c (revision 354717)
@@ -1,299 +1,425 @@
/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2018 Ruslan Bukin
* All rights reserved.
*
* This software was developed by SRI International and the University of
* Cambridge Computer Laboratory (Department of Computer Science and
* Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
* DARPA SSITH research programme.
*
* 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 THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR 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
__FBSDID("$FreeBSD$");
#include
#include
#include
#include
#include
#include
#include
#include
+#include
#include
#include
#include
#include
#include
#include "pic_if.h"
#define PLIC_MAX_IRQS 1024
-#define PLIC_PRIORITY(n) (0x000000 + (n) * 0x4)
-#define PLIC_ENABLE(n, h) (0x002000 + (h) * 0x80 + 4 * ((n) / 32))
-#define PLIC_THRESHOLD(h) (0x200000 + (h) * 0x1000 + 0x0)
-#define PLIC_CLAIM(h) (0x200000 + (h) * 0x1000 + 0x4)
+#define PLIC_PRIORITY_BASE 0x000000U
+
+#define PLIC_ENABLE_BASE 0x002000U
+#define PLIC_ENABLE_STRIDE 0x80U
+
+#define PLIC_CONTEXT_BASE 0x200000U
+#define PLIC_CONTEXT_STRIDE 0x1000U
+#define PLIC_CONTEXT_THRESHOLD 0x0U
+#define PLIC_CONTEXT_CLAIM 0x4U
+
+#define PLIC_PRIORITY(n) (PLIC_PRIORITY_BASE + (n) * sizeof(uint32_t))
+#define PLIC_ENABLE(sc, n, h) \
+ (sc->contexts[h].enable_offset + ((n) / 32) * sizeof(uint32_t))
+#define PLIC_THRESHOLD(sc, h) \
+ (sc->contexts[h].context_offset + PLIC_CONTEXT_THRESHOLD)
+#define PLIC_CLAIM(sc, h) \
+ (sc->contexts[h].context_offset + PLIC_CONTEXT_CLAIM)
+
struct plic_irqsrc {
struct intr_irqsrc isrc;
u_int irq;
};
+struct plic_context {
+ bus_size_t enable_offset;
+ bus_size_t context_offset;
+};
+
struct plic_softc {
device_t dev;
struct resource * intc_res;
struct plic_irqsrc isrcs[PLIC_MAX_IRQS];
+ struct plic_context contexts[MAXCPU];
int ndev;
};
#define RD4(sc, reg) \
bus_read_4(sc->intc_res, (reg))
#define WR4(sc, reg, val) \
bus_write_4(sc->intc_res, (reg), (val))
+static int
+riscv_hartid_to_cpu(int hartid)
+{
+ int i;
+
+ CPU_FOREACH(i) {
+ if (pcpu_find(i)->pc_hart == hartid)
+ return (i);
+ }
+
+ return (-1);
+}
+
+static int
+plic_get_hartid(device_t dev, phandle_t intc)
+{
+ int hart;
+
+ /* Check the interrupt controller layout. */
+ if (OF_searchencprop(intc, "#interrupt-cells", &hart,
+ sizeof(hart)) == -1) {
+ device_printf(dev,
+ "Could not find #interrupt-cells for phandle %u\n", intc);
+ return (-1);
+ }
+
+ /*
+ * The parent of the interrupt-controller is the CPU we are
+ * interested in, so search for its hart ID.
+ */
+ if (OF_searchencprop(OF_parent(intc), "reg", (pcell_t *)&hart,
+ sizeof(hart)) == -1) {
+ device_printf(dev, "Could not find hartid\n");
+ return (-1);
+ }
+
+ return (hart);
+}
+
static inline void
plic_irq_dispatch(struct plic_softc *sc, u_int irq,
struct trapframe *tf)
{
struct plic_irqsrc *src;
src = &sc->isrcs[irq];
if (intr_isrc_dispatch(&src->isrc, tf) != 0)
device_printf(sc->dev, "Stray irq %u detected\n", irq);
}
static int
plic_intr(void *arg)
{
struct plic_softc *sc;
struct trapframe *tf;
uint32_t pending;
uint32_t cpu;
sc = arg;
cpu = PCPU_GET(cpuid);
- pending = RD4(sc, PLIC_CLAIM(cpu));
+ pending = RD4(sc, PLIC_CLAIM(sc, cpu));
if (pending) {
tf = curthread->td_intr_frame;
plic_irq_dispatch(sc, pending, tf);
- WR4(sc, PLIC_CLAIM(cpu), pending);
+ WR4(sc, PLIC_CLAIM(sc, cpu), pending);
}
return (FILTER_HANDLED);
}
static void
plic_disable_intr(device_t dev, struct intr_irqsrc *isrc)
{
struct plic_softc *sc;
struct plic_irqsrc *src;
uint32_t reg;
uint32_t cpu;
sc = device_get_softc(dev);
src = (struct plic_irqsrc *)isrc;
cpu = PCPU_GET(cpuid);
- reg = RD4(sc, PLIC_ENABLE(src->irq, cpu));
+ reg = RD4(sc, PLIC_ENABLE(sc, src->irq, cpu));
reg &= ~(1 << (src->irq % 32));
- WR4(sc, PLIC_ENABLE(src->irq, cpu), reg);
+ WR4(sc, PLIC_ENABLE(sc, src->irq, cpu), reg);
}
static void
plic_enable_intr(device_t dev, struct intr_irqsrc *isrc)
{
struct plic_softc *sc;
struct plic_irqsrc *src;
uint32_t reg;
uint32_t cpu;
sc = device_get_softc(dev);
src = (struct plic_irqsrc *)isrc;
WR4(sc, PLIC_PRIORITY(src->irq), 1);
cpu = PCPU_GET(cpuid);
- reg = RD4(sc, PLIC_ENABLE(src->irq, cpu));
+ reg = RD4(sc, PLIC_ENABLE(sc, src->irq, cpu));
reg |= (1 << (src->irq % 32));
- WR4(sc, PLIC_ENABLE(src->irq, cpu), reg);
+ WR4(sc, PLIC_ENABLE(sc, src->irq, cpu), reg);
}
static int
plic_map_intr(device_t dev, struct intr_map_data *data,
struct intr_irqsrc **isrcp)
{
struct intr_map_data_fdt *daf;
struct plic_softc *sc;
sc = device_get_softc(dev);
if (data->type != INTR_MAP_DATA_FDT)
return (ENOTSUP);
daf = (struct intr_map_data_fdt *)data;
if (daf->ncells != 1 || daf->cells[0] > sc->ndev)
return (EINVAL);
*isrcp = &sc->isrcs[daf->cells[0]].isrc;
return (0);
}
static int
plic_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_is_compatible(dev, "riscv,plic0") &&
!ofw_bus_is_compatible(dev, "sifive,plic-1.0.0"))
return (ENXIO);
device_set_desc(dev, "RISC-V PLIC");
return (BUS_PROBE_DEFAULT);
}
static int
plic_attach(device_t dev)
{
struct plic_irqsrc *isrcs;
struct plic_softc *sc;
struct intr_pic *pic;
+ pcell_t *cells;
uint32_t irq;
const char *name;
phandle_t node;
phandle_t xref;
uint32_t cpu;
int error;
int rid;
+ int nintr;
+ int context;
+ int i;
+ int hart;
sc = device_get_softc(dev);
sc->dev = dev;
node = ofw_bus_get_node(dev);
if ((OF_getencprop(node, "riscv,ndev", &sc->ndev,
sizeof(sc->ndev))) < 0) {
device_printf(dev,
"Error: could not get number of devices\n");
return (ENXIO);
}
if (sc->ndev >= PLIC_MAX_IRQS) {
device_printf(dev,
"Error: invalid ndev (%d)\n", sc->ndev);
return (ENXIO);
}
/* Request memory resources */
rid = 0;
sc->intc_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
RF_ACTIVE);
if (sc->intc_res == NULL) {
device_printf(dev,
"Error: could not allocate memory resources\n");
return (ENXIO);
}
+ /* Register the interrupt sources */
isrcs = sc->isrcs;
name = device_get_nameunit(sc->dev);
cpu = PCPU_GET(cpuid);
for (irq = 1; irq <= sc->ndev; irq++) {
isrcs[irq].irq = irq;
error = intr_isrc_register(&isrcs[irq].isrc, sc->dev,
0, "%s,%u", name, irq);
if (error != 0)
return (error);
WR4(sc, PLIC_PRIORITY(irq), 0);
- WR4(sc, PLIC_ENABLE(irq, cpu), 0);
}
- WR4(sc, PLIC_THRESHOLD(cpu), 0);
+
+ /*
+ * Calculate the per-cpu enable and context register offsets.
+ *
+ * This is tricky for a few reasons. The PLIC divides the interrupt
+ * enable, threshold, and claim bits by "context", where each context
+ * routes to a Core-Local Interrupt Controller (CLIC).
+ *
+ * The tricky part is that the PLIC spec imposes no restrictions on how
+ * these contexts are laid out. So for example, there is no guarantee
+ * that each CPU will have both a machine mode and supervisor context,
+ * or that different PLIC implementations will organize the context
+ * registers in the same way. On top of this, we must handle the fact
+ * that cpuid != hartid, as they may have been renumbered during boot.
+ * We perform the following steps:
+ *
+ * 1. Examine the PLIC's "interrupts-extended" property and skip any
+ * entries that are not for supervisor external interrupts.
+ *
+ * 2. Walk up the device tree to find the corresponding CPU, and grab
+ * it's hart ID.
+ *
+ * 3. Convert the hart to a cpuid, and calculate the register offsets
+ * based on the context number.
+ */
+ nintr = OF_getencprop_alloc_multi(node, "interrupts-extended",
+ sizeof(uint32_t), (void **)&cells);
+ if (nintr <= 0) {
+ device_printf(dev, "Could not read interrupts-extended\n");
+ return (ENXIO);
+ }
+
+ /* interrupts-extended is a list of phandles and interrupt types. */
+ for (i = 0, context = 0; i < nintr; i += 2, context++) {
+ /* Skip M-mode external interrupts */
+ if (cells[i + 1] != IRQ_EXTERNAL_SUPERVISOR)
+ continue;
+
+ /* Get the hart ID from the CLIC's phandle. */
+ hart = plic_get_hartid(dev, OF_node_from_xref(cells[i]));
+ if (hart < 0) {
+ OF_prop_free(cells);
+ return (ENXIO);
+ }
+
+ /* Get the corresponding cpuid. */
+ cpu = riscv_hartid_to_cpu(hart);
+ if (cpu < 0) {
+ device_printf(dev, "Invalid hart!\n");
+ OF_prop_free(cells);
+ return (ENXIO);
+ }
+
+ /* Set the enable and context register offsets for the CPU. */
+ sc->contexts[cpu].enable_offset = PLIC_ENABLE_BASE +
+ context * PLIC_ENABLE_STRIDE;
+ sc->contexts[cpu].context_offset = PLIC_CONTEXT_BASE +
+ context * PLIC_CONTEXT_STRIDE;
+ }
+ OF_prop_free(cells);
+
+ WR4(sc, PLIC_THRESHOLD(sc, cpu), 0);
xref = OF_xref_from_node(node);
pic = intr_pic_register(sc->dev, xref);
if (pic == NULL)
return (ENXIO);
csr_set(sie, SIE_SEIE);
return (intr_pic_claim_root(sc->dev, xref, plic_intr, sc, 0));
}
static void
plic_pre_ithread(device_t dev, struct intr_irqsrc *isrc)
{
struct plic_softc *sc;
struct plic_irqsrc *src;
sc = device_get_softc(dev);
src = (struct plic_irqsrc *)isrc;
WR4(sc, PLIC_PRIORITY(src->irq), 0);
}
static void
plic_post_ithread(device_t dev, struct intr_irqsrc *isrc)
{
struct plic_softc *sc;
struct plic_irqsrc *src;
sc = device_get_softc(dev);
src = (struct plic_irqsrc *)isrc;
WR4(sc, PLIC_PRIORITY(src->irq), 1);
}
static device_method_t plic_methods[] = {
DEVMETHOD(device_probe, plic_probe),
DEVMETHOD(device_attach, plic_attach),
DEVMETHOD(pic_disable_intr, plic_disable_intr),
DEVMETHOD(pic_enable_intr, plic_enable_intr),
DEVMETHOD(pic_map_intr, plic_map_intr),
DEVMETHOD(pic_pre_ithread, plic_pre_ithread),
DEVMETHOD(pic_post_ithread, plic_post_ithread),
DEVMETHOD_END
};
static driver_t plic_driver = {
"plic",
plic_methods,
sizeof(struct plic_softc),
};
static devclass_t plic_devclass;
EARLY_DRIVER_MODULE(plic, simplebus, plic_driver, plic_devclass,
0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_MIDDLE);