Patchwork [v2,1/4] xilinx_zynq: added smp support

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Submitter Peter A. G. Crosthwaite
Date Oct. 4, 2012, 12:16 a.m.
Message ID <d1e7dcdf86f9b9cff2874fc831825c02f13452d7.1349308835.git.peter.crosthwaite@xilinx.com>
Download mbox | patch
Permalink /patch/188965/
State New
Headers show

Comments

Peter A. G. Crosthwaite - Oct. 4, 2012, 12:16 a.m.
From: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>

Added linux smp support for the xilinx zynq platform (2x cpus are supported)

Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
---
Changed from v1:
Addressed PMM review
Shorted secondary bootloop using MVN instruction.
Used default reset secondary instead of custom one.
Rebased against QOM cpu developments.
Few whitespace fixes.

 hw/xilinx_zynq.c |   57 ++++++++++++++++++++++++++++++++++++++++++-----------
 1 files changed, 45 insertions(+), 12 deletions(-)
Peter Maydell - Oct. 9, 2012, 11:52 a.m.
On 4 October 2012 01:16, Peter Crosthwaite
<peter.crosthwaite@petalogix.com> wrote:
> From: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
>
> Added linux smp support for the xilinx zynq platform (2x cpus are supported)
>
> Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
> ---
> Changed from v1:
> Addressed PMM review
> Shorted secondary bootloop using MVN instruction.
> Used default reset secondary instead of custom one.
> Rebased against QOM cpu developments.
> Few whitespace fixes.
>
>  hw/xilinx_zynq.c |   57 ++++++++++++++++++++++++++++++++++++++++++-----------
>  1 files changed, 45 insertions(+), 12 deletions(-)
>
> diff --git a/hw/xilinx_zynq.c b/hw/xilinx_zynq.c
> index 7e6c273..22a2bc5 100644
> --- a/hw/xilinx_zynq.c
> +++ b/hw/xilinx_zynq.c
> @@ -30,6 +30,32 @@
>
>  #define IRQ_OFFSET 32 /* pic interrupts start from index 32 */
>
> +#define SMP_BOOT_ADDR 0x0fff0000

What is at this address in real hardware? I can't see anything in the
machine model that maps at this address but I could be missing it.
(Generally we put the secondary bootloader in some place corresponding
to some kind of real RAM.)

> +#define SMP_BOOTREG_ADDR 0xfffffff0

...this is an address in the on-chip memory, right?

Other than those queries, patch looks OK.

-- PMM
Peter A. G. Crosthwaite - Oct. 9, 2012, 1:48 p.m.
On Tue, Oct 9, 2012 at 9:52 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
> On 4 October 2012 01:16, Peter Crosthwaite
> <peter.crosthwaite@petalogix.com> wrote:
>> From: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
>>
>> Added linux smp support for the xilinx zynq platform (2x cpus are supported)
>>
>> Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
>> ---
>> Changed from v1:
>> Addressed PMM review
>> Shorted secondary bootloop using MVN instruction.
>> Used default reset secondary instead of custom one.
>> Rebased against QOM cpu developments.
>> Few whitespace fixes.
>>
>>  hw/xilinx_zynq.c |   57 ++++++++++++++++++++++++++++++++++++++++++-----------
>>  1 files changed, 45 insertions(+), 12 deletions(-)
>>
>> diff --git a/hw/xilinx_zynq.c b/hw/xilinx_zynq.c
>> index 7e6c273..22a2bc5 100644
>> --- a/hw/xilinx_zynq.c
>> +++ b/hw/xilinx_zynq.c
>> @@ -30,6 +30,32 @@
>>
>>  #define IRQ_OFFSET 32 /* pic interrupts start from index 32 */
>>
>> +#define SMP_BOOT_ADDR 0x0fff0000
>
> What is at this address in real hardware? I can't see anything in the
> machine model that maps at this address but I could be missing it.
> (Generally we put the secondary bootloader in some place corresponding
> to some kind of real RAM.)
>

Main RAM (based at 0). We always pass -M big enough for this to not be
a problem. I guess we could force to ram big enough in the machine
model to catch the case where memory is too small.

>> +#define SMP_BOOTREG_ADDR 0xfffffff0
>
> ...this is an address in the on-chip memory, right?
>

Yes, Our bootrom does something similar for secondary CPU kicking, so
we chose that address to bring the machine as close to the actual boot
process as possible.

Regards,
Peter

> Other than those queries, patch looks OK.
>
> -- PMM

Patch

diff --git a/hw/xilinx_zynq.c b/hw/xilinx_zynq.c
index 7e6c273..22a2bc5 100644
--- a/hw/xilinx_zynq.c
+++ b/hw/xilinx_zynq.c
@@ -30,6 +30,32 @@ 
 
 #define IRQ_OFFSET 32 /* pic interrupts start from index 32 */
 
+#define SMP_BOOT_ADDR 0x0fff0000
+#define SMP_BOOTREG_ADDR 0xfffffff0
+
+/* Entry point for secondary CPU */
+static uint32_t zynq_smpboot[] = {
+    0xe3e0000f, /* ldr r0, =0xfffffff0 (mvn r0, #15) */
+    0xe320f002, /* wfe */
+    0xe5901000, /* ldr     r1, [r0] */
+    0xe1110001, /* tst     r1, r1 */
+    0x0afffffb, /* beq     <wfe> */
+    0xe12fff11, /* bx      r1 */
+    0,
+};
+
+static void zynq_write_secondary_boot(ARMCPU *cpu,
+                                      const struct arm_boot_info *info)
+{
+    int n;
+
+    for (n = 0; n < ARRAY_SIZE(zynq_smpboot); n++) {
+        zynq_smpboot[n] = tswap32(zynq_smpboot[n]);
+    }
+    rom_add_blob_fixed("smpboot", zynq_smpboot, sizeof(zynq_smpboot),
+                       SMP_BOOT_ADDR);
+}
+
 static struct arm_boot_info zynq_binfo = {};
 
 static void gem_init(NICInfo *nd, uint32_t base, qemu_irq irq)
@@ -50,7 +76,7 @@  static void zynq_init(ram_addr_t ram_size, const char *boot_device,
                         const char *kernel_filename, const char *kernel_cmdline,
                         const char *initrd_filename, const char *cpu_model)
 {
-    ARMCPU *cpu;
+    ARMCPU *cpus[2];
     MemoryRegion *address_space_mem = get_system_memory();
     MemoryRegion *ext_ram = g_new(MemoryRegion, 1);
     MemoryRegion *ocm_ram = g_new(MemoryRegion, 1);
@@ -60,19 +86,21 @@  static void zynq_init(ram_addr_t ram_size, const char *boot_device,
     qemu_irq pic[64];
     NICInfo *nd;
     int n;
-    qemu_irq cpu_irq;
+    qemu_irq cpu_irq[2];
 
     if (!cpu_model) {
         cpu_model = "cortex-a9";
     }
 
-    cpu = cpu_arm_init(cpu_model);
-    if (!cpu) {
-        fprintf(stderr, "Unable to find CPU definition\n");
-        exit(1);
+    for (n = 0; n < smp_cpus; n++) {
+        cpus[n] = cpu_arm_init(cpu_model);
+        if (!cpus[n]) {
+            fprintf(stderr, "Unable to find CPU definition\n");
+            exit(1);
+        }
+        irqp = arm_pic_init_cpu(cpus[n]);
+        cpu_irq[n] = irqp[ARM_PIC_CPU_IRQ];
     }
-    irqp = arm_pic_init_cpu(cpu);
-    cpu_irq = irqp[ARM_PIC_CPU_IRQ];
 
     /* max 2GB ram */
     if (ram_size > 0x80000000) {
@@ -103,11 +131,13 @@  static void zynq_init(ram_addr_t ram_size, const char *boot_device,
     sysbus_mmio_map(sysbus_from_qdev(dev), 0, 0xF8000000);
 
     dev = qdev_create(NULL, "a9mpcore_priv");
-    qdev_prop_set_uint32(dev, "num-cpu", 1);
+    qdev_prop_set_uint32(dev, "num-cpu", smp_cpus);
     qdev_init_nofail(dev);
     busdev = sysbus_from_qdev(dev);
     sysbus_mmio_map(busdev, 0, 0xF8F00000);
-    sysbus_connect_irq(busdev, 0, cpu_irq);
+    for (n = 0; n < smp_cpus; n++) {
+        sysbus_connect_irq(busdev, n, cpu_irq[n]);
+    }
 
     for (n = 0; n < 64; n++) {
         pic[n] = qdev_get_gpio_in(dev, n);
@@ -134,7 +164,10 @@  static void zynq_init(ram_addr_t ram_size, const char *boot_device,
     zynq_binfo.kernel_filename = kernel_filename;
     zynq_binfo.kernel_cmdline = kernel_cmdline;
     zynq_binfo.initrd_filename = initrd_filename;
-    zynq_binfo.nb_cpus = 1;
+    zynq_binfo.nb_cpus = smp_cpus;
+    zynq_binfo.write_secondary_boot = zynq_write_secondary_boot;
+    zynq_binfo.smp_loader_start = SMP_BOOT_ADDR;
+    zynq_binfo.smp_bootreg_addr = SMP_BOOTREG_ADDR;
     zynq_binfo.board_id = 0xd32;
     zynq_binfo.loader_start = 0;
     arm_load_kernel(arm_env_get_cpu(first_cpu), &zynq_binfo);
@@ -145,7 +178,7 @@  static QEMUMachine zynq_machine = {
     .desc = "Xilinx Zynq Platform Baseboard for Cortex-A9",
     .init = zynq_init,
     .use_scsi = 1,
-    .max_cpus = 1,
+    .max_cpus = 2,
     .no_sdcard = 1
 };