diff options
Diffstat (limited to 'arch/arm/cpu/armv7/tegra2/ap20.c')
-rw-r--r-- | arch/arm/cpu/armv7/tegra2/ap20.c | 329 |
1 files changed, 329 insertions, 0 deletions
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 +} |