[PATCH 1/6] ARM: cygnus: Initial support for Broadcom Cygnus SoC
Mark Rutland
mark.rutland at arm.com
Tue Sep 16 17:00:19 PDT 2014
On Tue, Sep 16, 2014 at 08:58:12PM +0100, Jonathan Richardson wrote:
> Adds initial support for the Cygnus SoC based on Broadcom’s iProc series.
>
> Reviewed-by: Ray Jui <rjui at broadcom.com>
> Reviewed-by: Desmond Liu <desmondl at broadcom.com>
> Reviewed-by: JD (Jiandong) Zheng <jdzheng at broadcom.com>
> Tested-by: Jonathan Richardson <jonathar at broadcom.com>
> Signed-off-by: Jonathan Richardson <jonathar at broadcom.com>
> ---
> arch/arm/mach-bcm/Kconfig | 34 +++++++
> arch/arm/mach-bcm/Makefile | 3 +
> arch/arm/mach-bcm/board_bcm_cygnus.c | 166 ++++++++++++++++++++++++++++++++++
Is Cygnus an SoC or a board?
> 3 files changed, 203 insertions(+)
> create mode 100644 arch/arm/mach-bcm/board_bcm_cygnus.c
>
> diff --git a/arch/arm/mach-bcm/Kconfig b/arch/arm/mach-bcm/Kconfig
> index fc93800..58e0f20 100644
> --- a/arch/arm/mach-bcm/Kconfig
> +++ b/arch/arm/mach-bcm/Kconfig
> @@ -5,6 +5,40 @@ menuconfig ARCH_BCM
>
> if ARCH_BCM
>
> +config ARCH_BCM_IPROC
> + bool "Broadcom ARMv7 iProc boards" if ARCH_MULTI_V7
> + select ARM_GIC
> + select CACHE_L2X0
> + select HAVE_ARM_SCU if SMP
I didn't spot any SMP code in this series.
> + select HAVE_ARM_TWD if LOCAL_TIMERS
> + select HAVE_CLK
> + select CLKSRC_OF
> + select CLKSRC_MMIO
> + select LOCAL_TIMERS if SMP
> + select GENERIC_CLOCKEVENTS_BUILD
You don't need to select this.
> + select GENERIC_CLOCKEVENTS
> + select ARM_GLOBAL_TIMER
> + select ARCH_REQUIRE_GPIOLIB
> + select ARM_AMBA
> + select PINCTRL
> + select DEBUG_UART_8250
> + help
> + This enables support for systems based on Broadcom IPROC architected SoCs.
> + The IPROC complex contains one or more ARM CPUs along with common
> + core periperals. Application specific SoCs are created by adding a
> + uArchitecture containing peripherals outside of the IPROC complex.
> + Currently supported SoCs are Cygnus.
> +
> +menu "iProc SoC based Machine types"
> + depends on ARCH_BCM_IPROC
> +
> + config ARCH_BCM_CYGNUS
> + bool "Support Broadcom Cygnus board"
> + select USB_ARCH_HAS_EHCI if USB_SUPPORT
> + help
> + Support for Broadcom Cygnus SoC.
> +endmenu
> +
> config ARCH_BCM_MOBILE
> bool "Broadcom Mobile SoC Support" if ARCH_MULTI_V7
> select ARCH_REQUIRE_GPIOLIB
> diff --git a/arch/arm/mach-bcm/Makefile b/arch/arm/mach-bcm/Makefile
> index b19a396..dd14a10 100644
> --- a/arch/arm/mach-bcm/Makefile
> +++ b/arch/arm/mach-bcm/Makefile
> @@ -10,6 +10,9 @@
> # of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> # GNU General Public License for more details.
>
> +# Cygnus
> +obj-$(CONFIG_ARCH_BCM_CYGNUS) += board_bcm_cygnus.o
> +
> # BCM281XX
> obj-$(CONFIG_ARCH_BCM_281XX) += board_bcm281xx.o
>
> diff --git a/arch/arm/mach-bcm/board_bcm_cygnus.c b/arch/arm/mach-bcm/board_bcm_cygnus.c
> new file mode 100644
> index 0000000..d67555a
> --- /dev/null
> +++ b/arch/arm/mach-bcm/board_bcm_cygnus.c
> @@ -0,0 +1,166 @@
> +/*
> + * Copyright 2014 Broadcom Corporation. All rights reserved.
> + *
> + * Unless you and Broadcom execute a separate written software license
> + * agreement governing use of this software, this software is licensed to you
> + * under the terms of the GNU General Public License version 2, available at
> + * http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
Why don't we point at the gnu.org copy as we do elsewhere?
> + */
> +
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/clocksource.h>
> +#include <linux/clk-provider.h>
> +#include <linux/delay.h>
> +#include <asm/mach/arch.h>
> +#include <asm/mach/map.h>
> +#include <asm/proc-fns.h>
> +#include <asm/hardware/cache-l2x0.h>
> +
> +#define CRMU_MAIL_BOX1 0x03024028
Please don't hard code addresses in board files.
> +#define CRMU_SOFT_RESET_CMD 0xFFFFFFFF
> +
> +/* CRU_RESET register */
> +static void * __iomem crmu_mail_box1_reg;
> +
> +#ifdef CONFIG_NEON
> +
> +#define CRU_BASE 0x1800e000
Another hard coded address that needs to go.
> +#define CRU_SIZE 0x34
> +#define CRU_CONTROL_OFFSET 0x0
> +#define CRU_PWRDWN_EN_OFFSET 0x4
> +#define CRU_PWRDWN_STATUS_OFFSET 0x8
> +#define CRU_NEON0_HW_RESET 6
> +#define CRU_CLAMP_ON_NEON0 20
> +#define CRU_PWRONIN_NEON0 21
> +#define CRU_PWRONOUT_NEON0 21
> +#define CRU_PWROKIN_NEON0 22
> +#define CRU_PWROKOUT_NEON0 22
> +#define CRU_STATUS_DELAY_NS 500
> +#define CRU_MAX_RETRY_COUNT 10
> +#define CRU_RETRY_INTVL_US 1
> +
> +/* Power up the NEON/VFPv3 block. */
> +static void bcm_cygnus_powerup_neon(void)
> +{
> + void * __iomem cru_base = ioremap_nocache(CRU_BASE, CRU_SIZE);
Why not plain ioremap?
> + u32 reg, i;
> +
> + BUG_ON(!cru_base);
This seems a little extreme. Can;t we continue without NEON?
> +
> + /* De-assert the neon hardware block reset */
> + reg = readl(cru_base + CRU_CONTROL_OFFSET);
> + reg &= ~(1 << CRU_NEON0_HW_RESET);
> + writel(reg, cru_base + CRU_CONTROL_OFFSET);
> +
> + /* Assert the power ON register bit */
> + reg = readl(cru_base + CRU_PWRDWN_EN_OFFSET);
> + reg |= (1 << CRU_PWRONIN_NEON0);
> + writel(reg, cru_base + CRU_PWRDWN_EN_OFFSET);
> +
> + /*
> + * Wait up to 10 usec in 1 usec increments for the
> + * status register to acknowledge the power ON assert
> + */
> + for (i = 0; i < CRU_MAX_RETRY_COUNT; i++) {
> + reg = readl(cru_base + CRU_PWRDWN_STATUS_OFFSET);
> + if (reg & CRU_PWRONOUT_NEON0)
> + break;
> +
> + udelay(CRU_RETRY_INTVL_US);
> + }
> +
> + if (i == CRU_MAX_RETRY_COUNT)
> + panic("NEON power ON register not acknowledged\n");
We can't just disable NEON if we fail to enable the HW block?
[...]
> +static void __init bcm_cygnus_timer_init(void)
> +{
> + /* Initialize all clocks declared in device tree */
> + of_clk_init(NULL);
> +
> + clocksource_of_init();
> +}
If you take a look at time_init in arch/arm/kernel/time.c you'll see
this is redundant.
Get rid of this.
> +
> +static void __init bcm_cygnus_init(void)
> +{
> + of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
> +
> + l2x0_of_init(0, ~0UL);
> +
> + crmu_mail_box1_reg = ioremap_nocache(CRMU_MAIL_BOX1, SZ_4);
Why not plain ioremap?
> + BUG_ON(!crmu_mail_box1_reg);
We only use this for reboot later on, so do we need to blow up so
spectacularly in this case?
> +
> +#ifdef CONFIG_NEON
> + bcm_cygnus_powerup_neon();
> +#endif
> +}
> +
> +/*
> + * Reset the system
> + */
> +void bcm_cygnus_restart(enum reboot_mode mode, const char *cmd)
> +{
> + /* Send reset command to M0 via Mailbox. */
> + writel(CRMU_SOFT_RESET_CMD, crmu_mail_box1_reg);
> + iounmap(crmu_mail_box1_reg);
> +
> + /* Wait for M0 to reset the chip. */
> + while (1)
> + cpu_do_idle();
> +}
This doesn't have to live in the machine descriptor. It could be a
separate driver.
Thanks,
Mark.
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