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authorTom Warren <twarren.nvidia@gmail.com>2011-04-14 12:18:06 +0000
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2011-04-27 19:38:09 +0200
commit74652cf684fc8678a3c5377b1532394e2025ea49 (patch)
tree9697858fc0ec70e1efec3efb26c73126b2acbdce /arch/arm/cpu
parentc2b626c199384e4111fb170062ee9e17c4bc2eaa (diff)
arm: Tegra2: add support for A9 CPU init
Signed-off-by: Tom Warren <twarren@nvidia.com>
Diffstat (limited to 'arch/arm/cpu')
-rw-r--r--arch/arm/cpu/armv7/start.S12
-rw-r--r--arch/arm/cpu/armv7/tegra2/Makefile2
-rw-r--r--arch/arm/cpu/armv7/tegra2/ap20.c329
-rw-r--r--arch/arm/cpu/armv7/tegra2/ap20.h104
-rw-r--r--arch/arm/cpu/armv7/tegra2/lowlevel_init.S94
5 files changed, 540 insertions, 1 deletions
diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S
index 6387b8b0aa..2929fc7e32 100644
--- a/arch/arm/cpu/armv7/start.S
+++ b/arch/arm/cpu/armv7/start.S
@@ -70,6 +70,18 @@ _end_vect:
_TEXT_BASE:
.word CONFIG_SYS_TEXT_BASE
+#ifdef CONFIG_TEGRA2
+/*
+ * Tegra2 uses 2 separate CPUs - the AVP (ARM7TDMI) and the CPU (dual A9s).
+ * U-Boot runs on the AVP first, setting things up for the CPU (PLLs,
+ * muxes, clocks, clamps, etc.). Then the AVP halts, and expects the CPU
+ * to pick up its reset vector, which points here.
+ */
+.globl _armboot_start
+_armboot_start:
+ .word _start
+#endif
+
/*
* These are defined in the board-specific linker script.
*/
diff --git a/arch/arm/cpu/armv7/tegra2/Makefile b/arch/arm/cpu/armv7/tegra2/Makefile
index 687c8871c5..f1ea915851 100644
--- a/arch/arm/cpu/armv7/tegra2/Makefile
+++ b/arch/arm/cpu/armv7/tegra2/Makefile
@@ -28,7 +28,7 @@ include $(TOPDIR)/config.mk
LIB = $(obj)lib$(SOC).o
SOBJS := lowlevel_init.o
-COBJS := board.o sys_info.o timer.o
+COBJS := ap20.o board.o sys_info.o timer.o
SRCS := $(SOBJS:.o=.S) $(COBJS:.o=.c)
OBJS := $(addprefix $(obj),$(COBJS) $(SOBJS))
diff --git a/arch/arm/cpu/armv7/tegra2/ap20.c b/arch/arm/cpu/armv7/tegra2/ap20.c
new file mode 100644
index 0000000000..d3e6797481
--- /dev/null
+++ b/arch/arm/cpu/armv7/tegra2/ap20.c
@@ -0,0 +1,329 @@
+/*
+* (C) Copyright 2010-2011
+* NVIDIA Corporation <www.nvidia.com>
+*
+* See file CREDITS for list of people who contributed to this
+* project.
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of
+* the License, or (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software
+* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+* MA 02111-1307 USA
+*/
+
+#include "ap20.h"
+#include <asm/io.h>
+#include <asm/arch/tegra2.h>
+#include <asm/arch/clk_rst.h>
+#include <asm/arch/pmc.h>
+#include <asm/arch/pinmux.h>
+#include <asm/arch/scu.h>
+#include <common.h>
+
+u32 s_first_boot = 1;
+
+static void enable_cpu_clock(int enable)
+{
+ struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 reg, clk;
+
+ /*
+ * NOTE:
+ * Regardless of whether the request is to enable or disable the CPU
+ * clock, every processor in the CPU complex except the master (CPU 0)
+ * will have it's clock stopped because the AVP only talks to the
+ * master. The AVP does not know (nor does it need to know) that there
+ * are multiple processors in the CPU complex.
+ */
+
+ if (enable) {
+ /* Wait until all clocks are stable */
+ udelay(PLL_STABILIZATION_DELAY);
+
+ writel(CCLK_BURST_POLICY, &clkrst->crc_cclk_brst_pol);
+ writel(SUPER_CCLK_DIVIDER, &clkrst->crc_super_cclk_div);
+ }
+
+ /* Fetch the register containing the main CPU complex clock enable */
+ reg = readl(&clkrst->crc_clk_out_enb_l);
+ reg |= CLK_ENB_CPU;
+
+ /*
+ * Read the register containing the individual CPU clock enables and
+ * always stop the clock to CPU 1.
+ */
+ clk = readl(&clkrst->crc_clk_cpu_cmplx);
+ clk |= CPU1_CLK_STP;
+
+ if (enable) {
+ /* Unstop the CPU clock */
+ clk &= ~CPU0_CLK_STP;
+ } else {
+ /* Stop the CPU clock */
+ clk |= CPU0_CLK_STP;
+ }
+
+ writel(clk, &clkrst->crc_clk_cpu_cmplx);
+ writel(reg, &clkrst->crc_clk_out_enb_l);
+}
+
+static int is_cpu_powered(void)
+{
+ struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
+
+ return (readl(&pmc->pmc_pwrgate_status) & CPU_PWRED) ? 1 : 0;
+}
+
+static void remove_cpu_io_clamps(void)
+{
+ struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
+ u32 reg;
+
+ /* Remove the clamps on the CPU I/O signals */
+ reg = readl(&pmc->pmc_remove_clamping);
+ reg |= CPU_CLMP;
+ writel(reg, &pmc->pmc_remove_clamping);
+
+ /* Give I/O signals time to stabilize */
+ udelay(IO_STABILIZATION_DELAY);
+}
+
+static void powerup_cpu(void)
+{
+ struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
+ u32 reg;
+ int timeout = IO_STABILIZATION_DELAY;
+
+ if (!is_cpu_powered()) {
+ /* Toggle the CPU power state (OFF -> ON) */
+ reg = readl(&pmc->pmc_pwrgate_toggle);
+ reg &= PARTID_CP;
+ reg |= START_CP;
+ writel(reg, &pmc->pmc_pwrgate_toggle);
+
+ /* Wait for the power to come up */
+ while (!is_cpu_powered()) {
+ if (timeout-- == 0)
+ printf("CPU failed to power up!\n");
+ else
+ udelay(10);
+ }
+
+ /*
+ * Remove the I/O clamps from CPU power partition.
+ * Recommended only on a Warm boot, if the CPU partition gets
+ * power gated. Shouldn't cause any harm when called after a
+ * cold boot according to HW, probably just redundant.
+ */
+ remove_cpu_io_clamps();
+ }
+}
+
+static void enable_cpu_power_rail(void)
+{
+ struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
+ u32 reg;
+
+ reg = readl(&pmc->pmc_cntrl);
+ reg |= CPUPWRREQ_OE;
+ writel(reg, &pmc->pmc_cntrl);
+
+ /*
+ * The TI PMU65861C needs a 3.75ms delay between enabling
+ * the power rail and enabling the CPU clock. This delay
+ * between SM1EN and SM1 is for switching time + the ramp
+ * up of the voltage to the CPU (VDD_CPU from PMU).
+ */
+ udelay(3750);
+}
+
+static void reset_A9_cpu(int reset)
+{
+ struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 reg, cpu;
+
+ /*
+ * NOTE: Regardless of whether the request is to hold the CPU in reset
+ * or take it out of reset, every processor in the CPU complex
+ * except the master (CPU 0) will be held in reset because the
+ * AVP only talks to the master. The AVP does not know that there
+ * are multiple processors in the CPU complex.
+ */
+
+ /* Hold CPU 1 in reset */
+ cpu = SET_DBGRESET1 | SET_DERESET1 | SET_CPURESET1;
+ writel(cpu, &clkrst->crc_cpu_cmplx_set);
+
+ reg = readl(&clkrst->crc_rst_dev_l);
+ if (reset) {
+ /* Now place CPU0 into reset */
+ cpu |= SET_DBGRESET0 | SET_DERESET0 | SET_CPURESET0;
+ writel(cpu, &clkrst->crc_cpu_cmplx_set);
+
+ /* Enable master CPU reset */
+ reg |= SWR_CPU_RST;
+ } else {
+ /* Take CPU0 out of reset */
+ cpu = CLR_DBGRESET0 | CLR_DERESET0 | CLR_CPURESET0;
+ writel(cpu, &clkrst->crc_cpu_cmplx_clr);
+
+ /* Disable master CPU reset */
+ reg &= ~SWR_CPU_RST;
+ }
+
+ writel(reg, &clkrst->crc_rst_dev_l);
+}
+
+static void clock_enable_coresight(int enable)
+{
+ struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 rst, clk, src;
+
+ rst = readl(&clkrst->crc_rst_dev_u);
+ clk = readl(&clkrst->crc_clk_out_enb_u);
+
+ if (enable) {
+ rst &= ~SWR_CSITE_RST;
+ clk |= CLK_ENB_CSITE;
+ } else {
+ rst |= SWR_CSITE_RST;
+ clk &= ~CLK_ENB_CSITE;
+ }
+
+ writel(clk, &clkrst->crc_clk_out_enb_u);
+ writel(rst, &clkrst->crc_rst_dev_u);
+
+ if (enable) {
+ /*
+ * Put CoreSight on PLLP_OUT0 (216 MHz) and divide it down by
+ * 1.5, giving an effective frequency of 144MHz.
+ * Set PLLP_OUT0 [bits31:30 = 00], and use a 7.1 divisor
+ * (bits 7:0), so 00000001b == 1.5 (n+1 + .5)
+ */
+ src = CLK_DIVIDER(NVBL_PLLP_KHZ, 144000);
+ writel(src, &clkrst->crc_clk_src_csite);
+
+ /* Unlock the CPU CoreSight interfaces */
+ rst = 0xC5ACCE55;
+ writel(rst, CSITE_CPU_DBG0_LAR);
+ writel(rst, CSITE_CPU_DBG1_LAR);
+ }
+}
+
+void start_cpu(u32 reset_vector)
+{
+ /* Enable VDD_CPU */
+ enable_cpu_power_rail();
+
+ /* Hold the CPUs in reset */
+ reset_A9_cpu(1);
+
+ /* Disable the CPU clock */
+ enable_cpu_clock(0);
+
+ /* Enable CoreSight */
+ clock_enable_coresight(1);
+
+ /*
+ * Set the entry point for CPU execution from reset,
+ * if it's a non-zero value.
+ */
+ if (reset_vector)
+ writel(reset_vector, EXCEP_VECTOR_CPU_RESET_VECTOR);
+
+ /* Enable the CPU clock */
+ enable_cpu_clock(1);
+
+ /* If the CPU doesn't already have power, power it up */
+ powerup_cpu();
+
+ /* Take the CPU out of reset */
+ reset_A9_cpu(0);
+}
+
+
+void halt_avp(void)
+{
+ for (;;) {
+ writel((HALT_COP_EVENT_JTAG | HALT_COP_EVENT_IRQ_1 \
+ | HALT_COP_EVENT_FIQ_1 | (FLOW_MODE_STOP<<29)),
+ FLOW_CTLR_HALT_COP_EVENTS);
+ }
+}
+
+void enable_scu(void)
+{
+ struct scu_ctlr *scu = (struct scu_ctlr *)NV_PA_ARM_PERIPHBASE;
+ u32 reg;
+
+ /* If SCU already setup/enabled, return */
+ if (readl(&scu->scu_ctrl) & SCU_CTRL_ENABLE)
+ return;
+
+ /* Invalidate all ways for all processors */
+ writel(0xFFFF, &scu->scu_inv_all);
+
+ /* Enable SCU - bit 0 */
+ reg = readl(&scu->scu_ctrl);
+ reg |= SCU_CTRL_ENABLE;
+ writel(reg, &scu->scu_ctrl);
+}
+
+void init_pmc_scratch(void)
+{
+ struct pmc_ctlr *const pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
+ int i;
+
+ /* SCRATCH0 is initialized by the boot ROM and shouldn't be cleared */
+ for (i = 0; i < 23; i++)
+ writel(0, &pmc->pmc_scratch1+i);
+
+ /* ODMDATA is for kernel use to determine RAM size, LP config, etc. */
+ writel(CONFIG_SYS_BOARD_ODMDATA, &pmc->pmc_scratch20);
+}
+
+void cpu_start(void)
+{
+ struct pmux_tri_ctlr *pmt = (struct pmux_tri_ctlr *)NV_PA_APB_MISC_BASE;
+
+ /* enable JTAG */
+ writel(0xC0, &pmt->pmt_cfg_ctl);
+
+ if (s_first_boot) {
+ /*
+ * Need to set this before cold-booting,
+ * otherwise we'll end up in an infinite loop.
+ */
+ s_first_boot = 0;
+ cold_boot();
+ }
+}
+
+void tegra2_start()
+{
+ if (s_first_boot) {
+ /* Init Debug UART Port (115200 8n1) */
+ uart_init();
+
+ /* Init PMC scratch memory */
+ init_pmc_scratch();
+ }
+
+#ifdef CONFIG_ENABLE_CORTEXA9
+ /* take the mpcore out of reset */
+ cpu_start();
+
+ /* configure cache */
+ cache_configure();
+#endif
+}
diff --git a/arch/arm/cpu/armv7/tegra2/ap20.h b/arch/arm/cpu/armv7/tegra2/ap20.h
new file mode 100644
index 0000000000..49fe340a28
--- /dev/null
+++ b/arch/arm/cpu/armv7/tegra2/ap20.h
@@ -0,0 +1,104 @@
+/*
+ * (C) Copyright 2010-2011
+ * NVIDIA Corporation <www.nvidia.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#include <asm/types.h>
+
+/* Stabilization delays, in usec */
+#define PLL_STABILIZATION_DELAY (300)
+#define IO_STABILIZATION_DELAY (1000)
+
+#define NVBL_PLLP_KHZ (216000)
+
+#define PLLX_ENABLED (1 << 30)
+#define CCLK_BURST_POLICY 0x20008888
+#define SUPER_CCLK_DIVIDER 0x80000000
+
+/* Calculate clock fractional divider value from ref and target frequencies */
+#define CLK_DIVIDER(REF, FREQ) ((((REF) * 2) / FREQ) - 2)
+
+/* Calculate clock frequency value from reference and clock divider value */
+#define CLK_FREQUENCY(REF, REG) (((REF) * 2) / (REG + 2))
+
+/* AVP/CPU ID */
+#define PG_UP_TAG_0_PID_CPU 0x55555555 /* CPU aka "a9" aka "mpcore" */
+#define PG_UP_TAG_0 0x0
+
+#define CORESIGHT_UNLOCK 0xC5ACCE55;
+
+/* AP20-Specific Base Addresses */
+
+/* AP20 Base physical address of SDRAM. */
+#define AP20_BASE_PA_SDRAM 0x00000000
+/* AP20 Base physical address of internal SRAM. */
+#define AP20_BASE_PA_SRAM 0x40000000
+/* AP20 Size of internal SRAM (256KB). */
+#define AP20_BASE_PA_SRAM_SIZE 0x00040000
+/* AP20 Base physical address of flash. */
+#define AP20_BASE_PA_NOR_FLASH 0xD0000000
+/* AP20 Base physical address of boot information table. */
+#define AP20_BASE_PA_BOOT_INFO AP20_BASE_PA_SRAM
+
+/*
+ * Super-temporary stacks for EXTREMELY early startup. The values chosen for
+ * these addresses must be valid on ALL SOCs because this value is used before
+ * we are able to differentiate between the SOC types.
+ *
+ * NOTE: The since CPU's stack will eventually be moved from IRAM to SDRAM, its
+ * stack is placed below the AVP stack. Once the CPU stack has been moved,
+ * the AVP is free to use the IRAM the CPU stack previously occupied if
+ * it should need to do so.
+ *
+ * NOTE: In multi-processor CPU complex configurations, each processor will have
+ * its own stack of size CPU_EARLY_BOOT_STACK_SIZE. CPU 0 will have a
+ * limit of CPU_EARLY_BOOT_STACK_LIMIT. Each successive CPU will have a
+ * stack limit that is CPU_EARLY_BOOT_STACK_SIZE less then the previous
+ * CPU.
+ */
+
+/* Common AVP early boot stack limit */
+#define AVP_EARLY_BOOT_STACK_LIMIT \
+ (AP20_BASE_PA_SRAM + (AP20_BASE_PA_SRAM_SIZE/2))
+/* Common AVP early boot stack size */
+#define AVP_EARLY_BOOT_STACK_SIZE 0x1000
+/* Common CPU early boot stack limit */
+#define CPU_EARLY_BOOT_STACK_LIMIT \
+ (AVP_EARLY_BOOT_STACK_LIMIT - AVP_EARLY_BOOT_STACK_SIZE)
+/* Common CPU early boot stack size */
+#define CPU_EARLY_BOOT_STACK_SIZE 0x1000
+
+#define EXCEP_VECTOR_CPU_RESET_VECTOR (NV_PA_EVP_BASE + 0x100)
+#define CSITE_CPU_DBG0_LAR (NV_PA_CSITE_BASE + 0x10FB0)
+#define CSITE_CPU_DBG1_LAR (NV_PA_CSITE_BASE + 0x12FB0)
+
+#define FLOW_CTLR_HALT_COP_EVENTS (NV_PA_FLOW_BASE + 4)
+#define FLOW_MODE_STOP 2
+#define HALT_COP_EVENT_JTAG (1 << 28)
+#define HALT_COP_EVENT_IRQ_1 (1 << 11)
+#define HALT_COP_EVENT_FIQ_1 (1 << 9)
+
+/* Prototypes */
+
+void tegra2_start(void);
+void uart_init(void);
+void udelay(unsigned long);
+void cold_boot(void);
+void cache_configure(void);
diff --git a/arch/arm/cpu/armv7/tegra2/lowlevel_init.S b/arch/arm/cpu/armv7/tegra2/lowlevel_init.S
index 7f15746861..f24a2ff57d 100644
--- a/arch/arm/cpu/armv7/tegra2/lowlevel_init.S
+++ b/arch/arm/cpu/armv7/tegra2/lowlevel_init.S
@@ -26,6 +26,7 @@
#include <config.h>
#include <version.h>
+
_TEXT_BASE:
.word CONFIG_SYS_TEXT_BASE @ sdram load addr from config file
@@ -58,8 +59,101 @@ lowlevel_init:
mov pc, lr @ back to arch calling code
+
+.globl startup_cpu
+startup_cpu:
+ @ Initialize the AVP, clocks, and memory controller
+ @ SDRAM is guaranteed to be on at this point
+
+ ldr r0, =cold_boot @ R0 = reset vector for CPU
+ bl start_cpu @ start the CPU
+
+ @ Transfer control to the AVP code
+ bl halt_avp
+
+ @ Should never get here
+_loop_forever2:
+ b _loop_forever2
+
+.globl cache_configure
+cache_configure:
+ stmdb r13!,{r14}
+ @ invalidate instruction cache
+ mov r1, #0
+ mcr p15, 0, r1, c7, c5, 0
+
+ @ invalidate the i&d tlb entries
+ mcr p15, 0, r1, c8, c5, 0
+ mcr p15, 0, r1, c8, c6, 0
+
+ @ enable instruction cache
+ mrc p15, 0, r1, c1, c0, 0
+ orr r1, r1, #(1<<12)
+ mcr p15, 0, r1, c1, c0, 0
+
+ bl enable_scu
+
+ @ enable SMP mode and FW for CPU0, by writing to Auxiliary Ctl reg
+ mrc p15, 0, r0, c1, c0, 1
+ orr r0, r0, #0x41
+ mcr p15, 0, r0, c1, c0, 1
+
+ @ Now flush the Dcache
+ mov r0, #0
+ @ 256 cache lines
+ mov r1, #256
+
+invalidate_loop:
+ add r1, r1, #-1
+ mov r0, r1, lsl #5
+ @ invalidate d-cache using line (way0)
+ mcr p15, 0, r0, c7, c6, 2
+
+ orr r2, r0, #(1<<30)
+ @ invalidate d-cache using line (way1)
+ mcr p15, 0, r2, c7, c6, 2
+
+ orr r2, r0, #(2<<30)
+ @ invalidate d-cache using line (way2)
+ mcr p15, 0, r2, c7, c6, 2
+
+ orr r2, r0, #(3<<30)
+ @ invalidate d-cache using line (way3)
+ mcr p15, 0, r2, c7, c6, 2
+ cmp r1, #0
+ bne invalidate_loop
+
+ @ FIXME: should have ap20's L2 disabled too?
+invalidate_done:
+ ldmia r13!,{pc}
+
+.globl cold_boot
+cold_boot:
+ msr cpsr_c, #0xD3
+ @ Check current processor: CPU or AVP?
+ @ If CPU, go to CPU boot code, else continue on AVP path
+
+ ldr r0, =NV_PA_PG_UP_BASE
+ ldr r1, [r0]
+ ldr r2, =PG_UP_TAG_AVP
+
+ @ are we the CPU?
+ ldr sp, CPU_STACK
+ cmp r1, r2
+ @ yep, we are the CPU
+ bne _armboot_start
+
+ @ AVP initialization follows this path
+ ldr sp, AVP_STACK
+ @ Init AVP and start CPU
+ b startup_cpu
+
@ the literal pools origin
.ltorg
SRAM_STACK:
.word LOW_LEVEL_SRAM_STACK
+AVP_STACK:
+ .word EARLY_AVP_STACK
+CPU_STACK:
+ .word EARLY_CPU_STACK