[PATCH v5 10/12] hw/mips: malta: Add KVM support

James Hogan
2014-06-17T22:14:13Z

In KVM mode the bootrom is loaded and executed from the last 1MB of
DRAM.

Based on "[PATCH 12/12] KVM/MIPS: General KVM support and support for
SMP Guests" by Sanjay Lal <sanjayl@kymasys.com>.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Sanjay Lal <sanjayl@kymasys.com>
---
Changes in v5:
- Kseg0 doesn't actually change size, so use cpu_mips_kseg0_to_phys()
rather than having the KVM specific cpu_mips_kvm_um_kseg0_to_phys().

Changes in v3:
- Remove unnecessary includes, especially linux/kvm.h which isn't a
good idea on non-Linux (Peter Maydell).

Changes in v2:
- Removal of cps / GIC / SMP support
- Minimal bootloader modified to execute safely from RAM
- Remove "Writing bootloader to final 1MB of RAM" printf
---
hw/mips/mips_malta.c | 73 ++++++++++++++++++++++++++++++++++++++--------------
1 file changed, 53 insertions(+), 20 deletions(-)

diff --git a/hw/mips/mips_malta.c b/hw/mips/mips_malta.c
index f4a7d4712952..8bc5392b4223 100644
--- a/hw/mips/mips_malta.c
+++ b/hw/mips/mips_malta.c
@@ -51,6 +51,7 @@
#include "sysemu/qtest.h"
#include "qemu/error-report.h"
#include "hw/empty_slot.h"
+#include "sysemu/kvm.h"

//#define DEBUG_BOARD_INIT

@@ -603,29 +604,31 @@ static void network_init(PCIBus *pci_bus)
*/

static void write_bootloader (CPUMIPSState *env, uint8_t *base,
- int64_t kernel_entry)
+ int64_t run_addr, int64_t kernel_entry)
{
uint32_t *p;

/* Small bootloader */
p = (uint32_t *)base;
- stl_p(p++, 0x0bf00160); /* j 0x1fc00580 */
+
+ stl_p(p++, 0x08000000 | /* j 0x1fc00580 */
+ ((run_addr + 0x580) & 0x0fffffff) >> 2);
stl_p(p++, 0x00000000); /* nop */

/* YAMON service vector */
- stl_p(base + 0x500, 0xbfc00580); /* start: */
- stl_p(base + 0x504, 0xbfc0083c); /* print_count: */
- stl_p(base + 0x520, 0xbfc00580); /* start: */
- stl_p(base + 0x52c, 0xbfc00800); /* flush_cache: */
- stl_p(base + 0x534, 0xbfc00808); /* print: */
- stl_p(base + 0x538, 0xbfc00800); /* reg_cpu_isr: */
- stl_p(base + 0x53c, 0xbfc00800); /* unred_cpu_isr: */
- stl_p(base + 0x540, 0xbfc00800); /* reg_ic_isr: */
- stl_p(base + 0x544, 0xbfc00800); /* unred_ic_isr: */
- stl_p(base + 0x548, 0xbfc00800); /* reg_esr: */
- stl_p(base + 0x54c, 0xbfc00800); /* unreg_esr: */
- stl_p(base + 0x550, 0xbfc00800); /* getchar: */
- stl_p(base + 0x554, 0xbfc00800); /* syscon_read: */
+ stl_p(base + 0x500, run_addr + 0x0580); /* start: */
+ stl_p(base + 0x504, run_addr + 0x083c); /* print_count: */
+ stl_p(base + 0x520, run_addr + 0x0580); /* start: */
+ stl_p(base + 0x52c, run_addr + 0x0800); /* flush_cache: */
+ stl_p(base + 0x534, run_addr + 0x0808); /* print: */
+ stl_p(base + 0x538, run_addr + 0x0800); /* reg_cpu_isr: */
+ stl_p(base + 0x53c, run_addr + 0x0800); /* unred_cpu_isr: */
+ stl_p(base + 0x540, run_addr + 0x0800); /* reg_ic_isr: */
+ stl_p(base + 0x544, run_addr + 0x0800); /* unred_ic_isr: */
+ stl_p(base + 0x548, run_addr + 0x0800); /* reg_esr: */
+ stl_p(base + 0x54c, run_addr + 0x0800); /* unreg_esr: */
+ stl_p(base + 0x550, run_addr + 0x0800); /* getchar: */
+ stl_p(base + 0x554, run_addr + 0x0800); /* syscon_read: */

/* Second part of the bootloader */
@@ -701,7 +704,7 @@ static void write_bootloader (CPUMIPSState *env, uint8_t *base,
p = (uint32_t *) (base + 0x800);
stl_p(p++, 0x03e00008); /* jr ra */
stl_p(p++, 0x24020000); /* li v0,0 */
- /* 808 YAMON print */
+ /* 808 YAMON print */
stl_p(p++, 0x03e06821); /* move t5,ra */
stl_p(p++, 0x00805821); /* move t3,a0 */
stl_p(p++, 0x00a05021); /* move t2,a1 */
@@ -774,6 +777,7 @@ static int64_t load_kernel (void)
uint32_t *prom_buf;
long prom_size;
int prom_index = 0;
+ uint64_t (*xlate_to_kseg0) (void *opaque, uint64_t addr);

#ifdef TARGET_WORDS_BIGENDIAN
big_endian = 1;
@@ -788,6 +792,11 @@ static int64_t load_kernel (void)
loaderparams.kernel_filename);
exit(1);
}
+ if (kvm_enabled()) {
+ xlate_to_kseg0 = cpu_mips_kvm_um_phys_to_kseg0;
+ } else {
+ xlate_to_kseg0 = cpu_mips_phys_to_kseg0;
+ }

/* load initrd */
initrd_size = 0;
@@ -820,7 +829,7 @@ static int64_t load_kernel (void)
prom_set(prom_buf, prom_index++, "%s", loaderparams.kernel_filename);
if (initrd_size > 0) {
prom_set(prom_buf, prom_index++, "rd_start=0x%" PRIx64 " rd_size=%li %s",
- cpu_mips_phys_to_kseg0(NULL, initrd_offset), initrd_size,
+ xlate_to_kseg0(NULL, initrd_offset), initrd_size,
loaderparams.kernel_cmdline);
} else {
prom_set(prom_buf, prom_index++, "%s", loaderparams.kernel_cmdline);
@@ -829,6 +838,7 @@ static int64_t load_kernel (void)
prom_set(prom_buf, prom_index++, "memsize");
prom_set(prom_buf, prom_index++, "%i",
MIN(loaderparams.ram_size, 256 << 20));
+
prom_set(prom_buf, prom_index++, "modetty0");
prom_set(prom_buf, prom_index++, "38400n8r");
prom_set(prom_buf, prom_index++, NULL);
@@ -863,6 +873,11 @@ static void main_cpu_reset(void *opaque)
}

malta_mips_config(cpu);
+
+ if (kvm_enabled()) {
+ /* Start running from the bootloader we wrote to end of RAM */
+ env->active_tc.PC = 0x40000000 + loaderparams.ram_size;
+ }
}

static void cpu_request_exit(void *opaque, int irq, int level)
@@ -878,6 +893,7 @@ static
void mips_malta_init(MachineState *machine)
{
ram_addr_t ram_size = machine->ram_size;
+ ram_addr_t ram_low_size;
const char *cpu_model = machine->cpu_model;
const char *kernel_filename = machine->kernel_filename;
const char *kernel_cmdline = machine->kernel_cmdline;
@@ -892,7 +908,7 @@ void mips_malta_init(MachineState *machine)
target_long bios_size = FLASH_SIZE;
const size_t smbus_eeprom_size = 8 * 256;
uint8_t *smbus_eeprom_buf = g_malloc0(smbus_eeprom_size);
- int64_t kernel_entry;
+ int64_t kernel_entry, bootloader_run_addr;
PCIBus *pci_bus;
ISABus *isa_bus;
MIPSCPU *cpu;
@@ -1011,13 +1027,30 @@ void mips_malta_init(MachineState *machine)
bios = pflash_cfi01_get_memory(fl);
fl_idx++;
if (kernel_filename) {
+ ram_low_size = MIN(ram_size, 256 << 20);
+ /* For KVM T&E we reserve 1MB of RAM for running bootloader */
+ if (kvm_enabled()) {
+ ram_low_size -= 0x100000;
+ bootloader_run_addr = 0x40000000 + ram_low_size;
+ } else {
+ bootloader_run_addr = 0xbfc00000;
+ }
+
/* Write a small bootloader to the flash location. */
- loaderparams.ram_size = MIN(ram_size, 256 << 20);
+ loaderparams.ram_size = ram_low_size;
loaderparams.kernel_filename = kernel_filename;
loaderparams.kernel_cmdline = kernel_cmdline;
loaderparams.initrd_filename = initrd_filename;
kernel_entry = load_kernel();
- write_bootloader(env, memory_region_get_ram_ptr(bios), kernel_entry);
+
+ write_bootloader(env, memory_region_get_ram_ptr(bios),
+ bootloader_run_addr, kernel_entry);
+ if (kvm_enabled()) {
+ /* Write the bootloader code @ the end of RAM, 1MB reserved */
+ write_bootloader(env, memory_region_get_ram_ptr(ram_low_preio) +
+ ram_low_size,
+ bootloader_run_addr, kernel_entry);
+ }
} else {
/* Load firmware from flash. */
if (!dinfo) {
--
1.9.3