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ARM: tegra: support for secondary cores on Tegra30 

Add support for bringing up secondary cores on Tegra30. On Tegra30 secondary
CPU cores are powergated, so we need to turn on the domains before we can bring
the CPU cores online. Bringing secondary cores online happens early during the
sytem boot, so we call powergating initialization from platform early_init
function.

Based on work by:

Scott Williams <scwilliams@nvidia.com>
Colin Cross <ccross@android.com>
Alex Frid <afrid@nvidia.com>

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Colin Cross <ccross@android.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
This commit is contained in:
Peter De Schrijver 2012-02-10 01:47:50 +02:00 committed by Olof Johansson
parent 65fe31da5c
commit 86e51a2ee4
2 changed files with 81 additions and 1 deletions
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32
arch/arm/mach-tegra/headsmp.S
View File

@ -164,6 +164,38 @@ __die:
str r1, [r7, #0x340] @ CLK_RST_CPU_CMPLX_SET
#endif
1:
#ifdef CONFIG_ARCH_TEGRA_3x_SOC
mov32 r6, TEGRA_FLOW_CTRL_BASE
cmp r10, #0
moveq r1, #FLOW_CTRL_HALT_CPU0_EVENTS
moveq r2, #FLOW_CTRL_CPU0_CSR
movne r1, r10, lsl #3
addne r2, r1, #(FLOW_CTRL_CPU1_CSR-8)
addne r1, r1, #(FLOW_CTRL_HALT_CPU1_EVENTS-8)
/* Clear CPU "event" and "interrupt" flags and power gate
it when halting but not before it is in the "WFI" state. */
ldr r0, [r6, +r2]
orr r0, r0, #FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG
orr r0, r0, #FLOW_CTRL_CSR_ENABLE
str r0, [r6, +r2]
/* Unconditionally halt this CPU */
mov r0, #FLOW_CTRL_WAITEVENT
str r0, [r6, +r1]
ldr r0, [r6, +r1] @ memory barrier
dsb
isb
wfi @ CPU should be power gated here
/* If the CPU didn't power gate above just kill it's clock. */
mov r0, r11, lsl #8
str r0, [r7, #348] @ CLK_CPU_CMPLX_SET
#endif
/* If the CPU still isn't dead, just spin here. */
b .
ENDPROC(__tegra_cpu_reset_handler)

50
arch/arm/mach-tegra/platsmp.c
View File

@ -24,7 +24,9 @@
#include <asm/mach-types.h>
#include <asm/smp_scu.h>
#include <mach/clk.h>
#include <mach/iomap.h>
#include <mach/powergate.h>
#include "fuse.h"
#include "flowctrl.h"
@ -42,6 +44,8 @@ static void __iomem *scu_base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE);
(IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x340)
#define CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR \
(IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x344)
#define CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR \
(IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x34c)
#define CPU_CLOCK(cpu) (0x1<<(8+cpu))
#define CPU_RESET(cpu) (0x1111ul<<(cpu))
@ -73,11 +77,52 @@ static int tegra20_power_up_cpu(unsigned int cpu)
return 0;
}
static int tegra30_power_up_cpu(unsigned int cpu)
{
u32 reg;
int ret, pwrgateid;
unsigned long timeout;
pwrgateid = tegra_cpu_powergate_id(cpu);
if (pwrgateid < 0)
return pwrgateid;
/* If this is the first boot, toggle powergates directly. */
if (!tegra_powergate_is_powered(pwrgateid)) {
ret = tegra_powergate_power_on(pwrgateid);
if (ret)
return ret;
/* Wait for the power to come up. */
timeout = jiffies + 10*HZ;
while (tegra_powergate_is_powered(pwrgateid)) {
if (time_after(jiffies, timeout))
return -ETIMEDOUT;
udelay(10);
}
}
/* CPU partition is powered. Enable the CPU clock. */
writel(CPU_CLOCK(cpu), CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR);
reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR);
udelay(10);
/* Remove I/O clamps. */
ret = tegra_powergate_remove_clamping(pwrgateid);
udelay(10);
/* Clear flow controller CSR. */
flowctrl_write_cpu_csr(cpu, 0);
return 0;
}
int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
{
int status;
/* Force the CPU into reset. The CPU must remain in reset when the
/*
* Force the CPU into reset. The CPU must remain in reset when the
* flow controller state is cleared (which will cause the flow
* controller to stop driving reset if the CPU has been power-gated
* via the flow controller). This will have no effect on first boot
@ -98,6 +143,9 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
case TEGRA20:
status = tegra20_power_up_cpu(cpu);
break;
case TEGRA30:
status = tegra30_power_up_cpu(cpu);
break;
default:
status = -EINVAL;
break;