2 * Jailhouse, a Linux-based partitioning hypervisor
4 * Copyright (c) ARM Limited, 2014
7 * Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
13 #include <jailhouse/cell.h>
14 #include <jailhouse/control.h>
15 #include <jailhouse/mmio.h>
16 #include <jailhouse/printk.h>
17 #include <asm/control.h>
18 #include <asm/gic_common.h>
19 #include <asm/irqchip.h>
20 #include <asm/percpu.h>
21 #include <asm/platform.h>
22 #include <asm/spinlock.h>
23 #include <asm/traps.h>
25 #define REG_RANGE(base, n, size) \
26 (base) ... ((base) + (n - 1) * (size))
28 extern void *gicd_base;
29 extern unsigned int gicd_size;
31 static DEFINE_SPINLOCK(dist_lock);
33 /* The GIC interface numbering does not necessarily match the logical map */
34 static u8 target_cpu_map[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
37 * Most of the GIC distributor writes only reconfigure the IRQs corresponding to
38 * the bits of the written value, by using separate `set' and `clear' registers.
39 * Such registers can be handled by setting the `is_poke' boolean, which allows
40 * to simply restrict the mmio->value with the cell configuration mask.
41 * Others, such as the priority registers, will need to be read and written back
42 * with a restricted value, by using the distributor lock.
44 static enum mmio_result
45 restrict_bitmask_access(struct mmio_access *mmio, unsigned int reg_index,
46 unsigned int bits_per_irq, bool is_poke)
48 struct cell *cell = this_cell();
50 unsigned long access_mask = 0;
52 * In order to avoid division, the number of bits per irq is limited
53 * to powers of 2 for the moment.
55 unsigned long irqs_per_reg = 32 >> ffsl(bits_per_irq);
56 unsigned long spi_bits = (1 << bits_per_irq) - 1;
57 /* First, extract the first interrupt affected by this access */
58 unsigned int first_irq = reg_index * irqs_per_reg;
60 /* For SGIs or PPIs, let the caller do the mmio access */
61 if (!is_spi(first_irq)) {
62 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
66 /* For SPIs, compare against the cell config mask */
68 for (spi = first_irq; spi < first_irq + irqs_per_reg; spi++) {
69 unsigned int bit_nr = (spi - first_irq) * bits_per_irq;
70 if (spi_in_cell(cell, spi))
71 access_mask |= spi_bits << bit_nr;
74 if (!mmio->is_write) {
75 /* Restrict the read value */
76 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
77 mmio->value &= access_mask;
83 * Modify the existing value of this register by first reading
85 * Relies on a spinlock since we need two mmio accesses.
87 unsigned long access_val = mmio->value;
89 spin_lock(&dist_lock);
91 mmio->is_write = false;
92 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
93 mmio->is_write = true;
96 mmio->value &= ~(access_mask & ~access_val);
97 mmio->value |= access_val;
98 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
100 spin_unlock(&dist_lock);
102 mmio->value &= access_mask;
103 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
109 * GICv3 uses a 64bit register IROUTER for each IRQ
111 static enum mmio_result handle_irq_route(struct mmio_access *mmio,
114 struct cell *cell = this_cell();
117 /* Ignore aff3 on AArch32 (return 0) */
118 if (mmio->size == 4 && (mmio->address % 8))
121 /* SGIs and PPIs are res0 */
126 * Ignore accesses to SPIs that do not belong to the cell. This isn't
127 * forbidden, because the guest driver may simply iterate over all
128 * registers at initialisation
130 if (!spi_in_cell(cell, irq - 32))
133 /* Translate the virtual cpu id into the physical one */
134 if (mmio->is_write) {
135 mmio->value = arm_cpu_virt2phys(cell, mmio->value);
136 if (mmio->value == -1) {
137 printk("Attempt to route IRQ%d outside of cell\n", irq);
140 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
142 cpu = mmio_read32(gicd_base + GICD_IROUTER + 8 * irq);
143 mmio->value = arm_cpu_phys2virt(cpu);
149 * GICv2 uses 8bit values for each IRQ in the ITARGETRs registers
151 static enum mmio_result handle_irq_target(struct mmio_access *mmio,
155 * ITARGETSR contain one byte per IRQ, so the first one affected by this
156 * access corresponds to the reg index
158 struct cell *cell = this_cell();
160 unsigned int spi = reg - 32;
166 * Let the guest freely access its SGIs and PPIs, which may be used to
167 * fill its CPU interface map.
170 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
175 * The registers are byte-accessible, extend the access to a word if
179 mmio->value <<= 8 * offset;
183 for (i = 0; i < 4; i++, spi++) {
184 if (spi_in_cell(cell, spi))
185 access_mask |= 0xff << (8 * i);
192 targets = (mmio->value >> (8 * i)) & 0xff;
194 /* Check that the targeted interface belongs to the cell */
195 for (cpu = 0; cpu < 8; cpu++) {
196 if (!(targets & target_cpu_map[cpu]))
199 if (per_cpu(cpu)->cell == cell)
202 printk("Attempt to route SPI%d outside of cell\n", spi);
207 if (mmio->is_write) {
208 spin_lock(&dist_lock);
210 mmio_read32(gicd_base + GICD_ITARGETSR + reg + offset);
211 mmio->value &= access_mask;
212 /* Combine with external SPIs */
213 mmio->value |= (itargetsr & ~access_mask);
214 /* And do the access */
215 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
216 spin_unlock(&dist_lock);
218 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
219 mmio->value &= access_mask;
225 static enum mmio_result handle_sgir_access(struct mmio_access *mmio)
228 unsigned long val = mmio->value;
233 sgi.targets = (val >> 16) & 0xff;
234 sgi.routing_mode = (val >> 24) & 0x3;
240 gic_handle_sgir_write(&sgi, false);
245 * Get the CPU interface ID for this cpu. It can be discovered by reading
246 * the banked value of the PPI and IPI TARGET registers
247 * Patch 2bb3135 in Linux explains why the probe may need to scans the first 8
248 * registers: some early implementation returned 0 for the first ITARGETSR
250 * Since those didn't have virtualization extensions, we can safely ignore that
253 int gic_probe_cpu_id(unsigned int cpu)
255 if (cpu >= ARRAY_SIZE(target_cpu_map))
258 target_cpu_map[cpu] = mmio_read32(gicd_base + GICD_ITARGETSR);
260 if (target_cpu_map[cpu] == 0)
266 void gic_handle_sgir_write(struct sgi *sgi, bool virt_input)
268 struct per_cpu *cpu_data = this_cpu_data();
270 unsigned long targets;
271 unsigned int this_cpu = cpu_data->cpu_id;
272 struct cell *cell = cpu_data->cell;
273 bool is_target = false;
275 cpu_data->stats[JAILHOUSE_CPU_STAT_VMEXITS_VSGI]++;
277 targets = sgi->targets;
280 /* Filter the targets */
281 for_each_cpu_except(cpu, cell->cpu_set, this_cpu) {
283 * When using a cpu map to target the different CPUs (GICv2),
284 * they are independent from the physical CPU IDs, so there is
285 * no need to translate them to the hypervisor's virtual IDs.
288 is_target = !!test_bit(arm_cpu_phys2virt(cpu),
291 is_target = !!(targets & target_cpu_map[cpu]);
293 if (sgi->routing_mode == 0 && !is_target)
296 irqchip_set_pending(per_cpu(cpu), sgi->id, false);
297 sgi->targets |= (1 << cpu);
300 /* Let the other CPUS inject their SGIs */
301 sgi->id = SGI_INJECT;
302 irqchip_send_sgi(sgi);
305 enum mmio_result gic_handle_dist_access(void *arg, struct mmio_access *mmio)
307 unsigned long reg = mmio->address;
308 enum mmio_result ret;
311 case REG_RANGE(GICD_IROUTER, 1024, 8):
312 ret = handle_irq_route(mmio, (reg - GICD_IROUTER) / 8);
315 case REG_RANGE(GICD_ITARGETSR, 1024, 1):
316 ret = handle_irq_target(mmio, reg - GICD_ITARGETSR);
319 case REG_RANGE(GICD_ICENABLER, 32, 4):
320 case REG_RANGE(GICD_ISENABLER, 32, 4):
321 case REG_RANGE(GICD_ICPENDR, 32, 4):
322 case REG_RANGE(GICD_ISPENDR, 32, 4):
323 case REG_RANGE(GICD_ICACTIVER, 32, 4):
324 case REG_RANGE(GICD_ISACTIVER, 32, 4):
325 ret = restrict_bitmask_access(mmio, (reg & 0x7f) / 4, 1, true);
328 case REG_RANGE(GICD_IGROUPR, 32, 4):
329 ret = restrict_bitmask_access(mmio, (reg & 0x7f) / 4, 1, false);
332 case REG_RANGE(GICD_ICFGR, 64, 4):
333 ret = restrict_bitmask_access(mmio, (reg & 0xff) / 4, 2, false);
336 case REG_RANGE(GICD_IPRIORITYR, 255, 4):
337 ret = restrict_bitmask_access(mmio, (reg & 0x3ff) / 4, 8,
342 ret = handle_sgir_access(mmio);
348 case REG_RANGE(GICD_PIDR0, 4, 4):
349 case REG_RANGE(GICD_PIDR4, 4, 4):
350 case REG_RANGE(GICD_CIDR0, 4, 4):
351 /* Allow read access, ignore write */
353 arm_mmio_perform_access((unsigned long)gicd_base, mmio);
363 void gic_handle_irq(struct per_cpu *cpu_data)
365 bool handled = false;
369 /* Read IAR1: set 'active' state */
370 irq_id = gic_read_iar();
372 if (irq_id == 0x3ff) /* Spurious IRQ */
376 if (is_sgi(irq_id)) {
377 arch_handle_sgi(cpu_data, irq_id);
380 handled = arch_handle_phys_irq(cpu_data, irq_id);
384 * Write EOIR1: drop priority, but stay active if handled is
386 * This allows to not be re-interrupted by a level-triggered
387 * interrupt that needs handling in the guest (e.g. timer)
389 irqchip_eoi_irq(irq_id, handled);
393 void gic_target_spis(struct cell *config_cell, struct cell *dest_cell)
395 unsigned int i, first_cpu, cpu_itf;
396 unsigned int shift = 0;
397 void *itargetsr = gicd_base + GICD_ITARGETSR;
402 /* Always route to the first logical CPU on reset */
403 for_each_cpu(first_cpu, dest_cell->cpu_set)
406 cpu_itf = target_cpu_map[first_cpu];
408 /* ITARGETSR0-7 contain the PPIs and SGIs, and are read-only. */
411 for (i = 0; i < 64; i++, shift = (shift + 8) % 32) {
412 if (spi_in_cell(config_cell, i)) {
413 mask |= (0xff << shift);
414 bits |= (cpu_itf << shift);
417 /* ITARGETRs have 4 IRQ per register */
418 if ((i + 1) % 4 == 0) {
419 targets = mmio_read32(itargetsr);
422 mmio_write32(itargetsr, targets);