On Wed, Apr 25, 2012 at 02:07:36PM +0300, Hiroshi DOYU wrote:
> The AHB Bus conforms to the AMBA Specification (Rev 2.0) Advanced
> High-performance Bus (AHB) architecture.
>
> The AHB Arbiter controls AHB bus master arbitration. This effectively
> forms a second level of arbitration for access to the memory
> controller through the AHB Slave Memory device. The AHB pre-fetch
> logic can be configured to enhance performance for devices doing
> sequential access. Each AHB master is assigned to either the high or
> low priority bin. Both Tegra20/30 have this AHB bus.
>
> Some of configuration param could be passed from DT too.
>
> Signed-off-by: Hiroshi DOYU <hdoyu@xxxxxxxxxx>
> Cc: Felipe Balbi <balbi@xxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> v4:
> Fixed the comments from Felipe/Russell.
> This is now located under drivers/platform/arm.
> v3:
> Use platform_device to get info from dt dynamically.(Felipe/Arnd)
>
> Signed-off-by: Hiroshi DOYU <hdoyu@xxxxxxxxxx>
Just one thing, you seem to have missed Russell's comment about this
driver being generic. You still add a TEGRA_AHB driver, also, you don't
need <mach/iomap.h>. Apart from those, you can add:
Reviewed-by: Felipe Balbi <balbi@xxxxxx>
> ---
> drivers/platform/Kconfig | 5 +
> drivers/platform/Makefile | 1 +
> drivers/platform/arm/Kconfig | 8 +
> drivers/platform/arm/Makefile | 5 +
> drivers/platform/arm/tegra-ahb.c | 278 ++++++++++++++++++++++++++++++++++++++
> 5 files changed, 297 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/platform/Kconfig b/drivers/platform/Kconfig
> index 8390dca..8b96a77 100644
> --- a/drivers/platform/Kconfig
> +++ b/drivers/platform/Kconfig
> @@ -1,3 +1,8 @@
> if X86
> source "drivers/platform/x86/Kconfig"
> endif
> +
> +if ARM
> +source "drivers/platform/arm/Kconfig"
> +endif
> +
> diff --git a/drivers/platform/Makefile b/drivers/platform/Makefile
> index 782953a..7a2b16f 100644
> --- a/drivers/platform/Makefile
> +++ b/drivers/platform/Makefile
> @@ -3,3 +3,4 @@
> #
>
> obj-$(CONFIG_X86) += x86/
> +obj-$(CONFIG_ARM) += arm/
> diff --git a/drivers/platform/arm/Kconfig b/drivers/platform/arm/Kconfig
> new file mode 100644
> index 0000000..0af31db
> --- /dev/null
> +++ b/drivers/platform/arm/Kconfig
> @@ -0,0 +1,8 @@
> +config TEGRA_AHB
> + bool "Enable AHB driver for NVIDIA Tegra SoCs"
> + depends on ARCH_TEGRA
> + default y
> + help
> + Adds AHB configuration functionality for NVIDIA Tegra SoCs,
> + which controls AHB bus master arbitration and some
> + perfomance parameters(priority, prefech size).
> diff --git a/drivers/platform/arm/Makefile b/drivers/platform/arm/Makefile
> new file mode 100644
> index 0000000..3535f56
> --- /dev/null
> +++ b/drivers/platform/arm/Makefile
> @@ -0,0 +1,5 @@
> +#
> +# Makefile for linux/drivers/platform/arm
> +# ARM Platform-Specific Drivers
> +#
> +obj-$(CONFIG_TEGRA_AHB) += tegra-ahb.o
> diff --git a/drivers/platform/arm/tegra-ahb.c b/drivers/platform/arm/tegra-ahb.c
> new file mode 100644
> index 0000000..dcad2ec
> --- /dev/null
> +++ b/drivers/platform/arm/tegra-ahb.c
> @@ -0,0 +1,278 @@
> +/*
> + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
> + * Copyright (C) 2011 Google, Inc.
> + *
> + * Author:
> + * Jay Cheng <jacheng@xxxxxxxxxx>
> + * James Wylder <james.wylder@xxxxxxxxxxxx>
> + * Benoit Goby <benoit@xxxxxxxxxxx>
> + * Colin Cross <ccross@xxxxxxxxxxx>
> + * Hiroshi DOYU <hdoyu@xxxxxxxxxx>
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/io.h>
> +
> +#include <mach/iomap.h>
why do you need mach/iomap.h ?
> +#define DRV_NAME "tegra-ahb"
> +
> +#define AHB_ARBITRATION_DISABLE 0x00
> +#define AHB_ARBITRATION_PRIORITY_CTRL 0x04
> +#define AHB_PRIORITY_WEIGHT(x) (((x) & 0x7) << 29)
> +#define PRIORITY_SELECT_USB BIT(6)
> +#define PRIORITY_SELECT_USB2 BIT(18)
> +#define PRIORITY_SELECT_USB3 BIT(17)
> +
> +#define AHB_GIZMO_AHB_MEM 0x0c
> +#define ENB_FAST_REARBITRATE BIT(2)
> +#define DONT_SPLIT_AHB_WR BIT(7)
> +
> +#define AHB_GIZMO_APB_DMA 0x10
> +#define AHB_GIZMO_IDE 0x18
> +#define AHB_GIZMO_USB 0x1c
> +#define AHB_GIZMO_AHB_XBAR_BRIDGE 0x20
> +#define AHB_GIZMO_CPU_AHB_BRIDGE 0x24
> +#define AHB_GIZMO_COP_AHB_BRIDGE 0x28
> +#define AHB_GIZMO_XBAR_APB_CTLR 0x2c
> +#define AHB_GIZMO_VCP_AHB_BRIDGE 0x30
> +#define AHB_GIZMO_NAND 0x3c
> +#define AHB_GIZMO_SDMMC4 0x44
> +#define AHB_GIZMO_XIO 0x48
> +#define AHB_GIZMO_BSEV 0x60
> +#define AHB_GIZMO_BSEA 0x70
> +#define AHB_GIZMO_NOR 0x74
> +#define AHB_GIZMO_USB2 0x78
> +#define AHB_GIZMO_USB3 0x7c
> +#define IMMEDIATE BIT(18)
> +
> +#define AHB_GIZMO_SDMMC1 0x80
> +#define AHB_GIZMO_SDMMC2 0x84
> +#define AHB_GIZMO_SDMMC3 0x88
> +#define AHB_MEM_PREFETCH_CFG_X 0xd8
> +#define AHB_ARBITRATION_XBAR_CTRL 0xdc
> +#define AHB_MEM_PREFETCH_CFG3 0xe0
> +#define AHB_MEM_PREFETCH_CFG4 0xe4
> +#define AHB_MEM_PREFETCH_CFG1 0xec
> +#define AHB_MEM_PREFETCH_CFG2 0xf0
> +#define PREFETCH_ENB BIT(31)
> +#define MST_ID(x) (((x) & 0x1f) << 26)
> +#define AHBDMA_MST_ID MST_ID(5)
> +#define USB_MST_ID MST_ID(6)
> +#define USB2_MST_ID MST_ID(18)
> +#define USB3_MST_ID MST_ID(17)
> +#define ADDR_BNDRY(x) (((x) & 0xf) << 21)
> +#define INACTIVITY_TIMEOUT(x) (((x) & 0xffff) << 0)
> +
> +#define AHB_ARBITRATION_AHB_MEM_WRQUE_MST_ID 0xf8
> +
> +static u32 tegra_ahb_gizmo[] = {
> + AHB_ARBITRATION_DISABLE,
> + AHB_ARBITRATION_PRIORITY_CTRL,
> + AHB_GIZMO_AHB_MEM,
> + AHB_GIZMO_APB_DMA,
> + AHB_GIZMO_IDE,
> + AHB_GIZMO_USB,
> + AHB_GIZMO_AHB_XBAR_BRIDGE,
> + AHB_GIZMO_CPU_AHB_BRIDGE,
> + AHB_GIZMO_COP_AHB_BRIDGE,
> + AHB_GIZMO_XBAR_APB_CTLR,
> + AHB_GIZMO_VCP_AHB_BRIDGE,
> + AHB_GIZMO_NAND,
> + AHB_GIZMO_SDMMC4,
> + AHB_GIZMO_XIO,
> + AHB_GIZMO_BSEV,
> + AHB_GIZMO_BSEA,
> + AHB_GIZMO_NOR,
> + AHB_GIZMO_USB2,
> + AHB_GIZMO_USB3,
> + AHB_GIZMO_SDMMC1,
> + AHB_GIZMO_SDMMC2,
> + AHB_GIZMO_SDMMC3,
> + AHB_MEM_PREFETCH_CFG_X,
> + AHB_ARBITRATION_XBAR_CTRL,
> + AHB_MEM_PREFETCH_CFG3,
> + AHB_MEM_PREFETCH_CFG4,
> + AHB_MEM_PREFETCH_CFG1,
> + AHB_MEM_PREFETCH_CFG2,
> + AHB_ARBITRATION_AHB_MEM_WRQUE_MST_ID,
> +};
> +
> +struct tegra_ahb {
> + void __iomem *regs;
> + void *ctx;
> + struct device *dev;
> +};
> +
> +static inline u32 gizmo_readl(struct tegra_ahb *ahb, u32 offset)
> +{
> + return readl(ahb->regs + offset);
> +}
> +
> +static inline void gizmo_writel(struct tegra_ahb *ahb, u32 value, u32 offset)
> +{
> + writel(value, ahb->regs + offset);
> +}
> +
> +static int tegra_ahb_suspend(struct device *dev)
> +{
> + int i;
> + struct tegra_ahb *ahb = dev_get_drvdata(dev);
> + u32 *p = ahb->ctx;
> +
> + for (i = 0; i < ARRAY_SIZE(tegra_ahb_gizmo); i++)
> + p[i] = gizmo_readl(ahb, tegra_ahb_gizmo[i]);
> + return 0;
> +}
> +
> +static int tegra_ahb_resume(struct device *dev)
> +{
> + int i;
> + struct tegra_ahb *ahb = dev_get_drvdata(dev);
> + u32 *p = ahb->ctx;
> +
> + for (i = 0; i < ARRAY_SIZE(tegra_ahb_gizmo); i++)
> + gizmo_writel(ahb, p[i], tegra_ahb_gizmo[i]);
> + return 0;
> +}
> +
> +static UNIVERSAL_DEV_PM_OPS(tegra_ahb_pm,
> + tegra_ahb_suspend,
> + tegra_ahb_resume, NULL);
> +
> +static void tegra_ahb_gizmo_init(struct tegra_ahb *ahb)
> +{
> + u32 val;
> +
> + val = gizmo_readl(ahb, AHB_GIZMO_AHB_MEM);
> + val |= ENB_FAST_REARBITRATE | IMMEDIATE | DONT_SPLIT_AHB_WR;
> + gizmo_writel(ahb, val, AHB_GIZMO_AHB_MEM);
> +
> + val = gizmo_readl(ahb, AHB_GIZMO_USB);
> + val |= IMMEDIATE;
> + gizmo_writel(ahb, val, AHB_GIZMO_USB);
> +
> + val = gizmo_readl(ahb, AHB_GIZMO_USB2);
> + val |= IMMEDIATE;
> + gizmo_writel(ahb, val, AHB_GIZMO_USB2);
> +
> + val = gizmo_readl(ahb, AHB_GIZMO_USB3);
> + val |= IMMEDIATE;
> + gizmo_writel(ahb, val, AHB_GIZMO_USB3);
> +
> + val = gizmo_readl(ahb, AHB_ARBITRATION_PRIORITY_CTRL);
> + val |= PRIORITY_SELECT_USB |
> + PRIORITY_SELECT_USB2 |
> + PRIORITY_SELECT_USB3 |
> + AHB_PRIORITY_WEIGHT(7);
> + gizmo_writel(ahb, val, AHB_ARBITRATION_PRIORITY_CTRL);
> +
> + val = gizmo_readl(ahb, AHB_MEM_PREFETCH_CFG1);
> + val &= ~MST_ID(~0);
> + val |= PREFETCH_ENB |
> + AHBDMA_MST_ID |
> + ADDR_BNDRY(0xc) |
> + INACTIVITY_TIMEOUT(0x1000);
> + gizmo_writel(ahb, val, AHB_MEM_PREFETCH_CFG1);
> +
> + val = gizmo_readl(ahb, AHB_MEM_PREFETCH_CFG2);
> + val &= ~MST_ID(~0);
> + val |= PREFETCH_ENB |
> + USB_MST_ID |
> + ADDR_BNDRY(0xc) |
> + INACTIVITY_TIMEOUT(0x1000);
> + gizmo_writel(ahb, val, AHB_MEM_PREFETCH_CFG2);
> +
> + val = gizmo_readl(ahb, AHB_MEM_PREFETCH_CFG3);
> + val &= ~MST_ID(~0);
> + val |= PREFETCH_ENB |
> + USB3_MST_ID |
> + ADDR_BNDRY(0xc) |
> + INACTIVITY_TIMEOUT(0x1000);
> + gizmo_writel(ahb, val, AHB_MEM_PREFETCH_CFG3);
> +
> + val = gizmo_readl(ahb, AHB_MEM_PREFETCH_CFG4);
> + val &= ~MST_ID(~0);
> + val |= PREFETCH_ENB |
> + USB2_MST_ID |
> + ADDR_BNDRY(0xc) |
> + INACTIVITY_TIMEOUT(0x1000);
> + gizmo_writel(ahb, val, AHB_MEM_PREFETCH_CFG4);
> +}
> +
> +static int __devinit tegra_ahb_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct tegra_ahb *ahb;
> + size_t bytes;
> +
> + bytes = sizeof(*ahb) + sizeof(u32) * ARRAY_SIZE(tegra_ahb_gizmo);
> + ahb = devm_kzalloc(&pdev->dev, bytes, GFP_KERNEL);
> + if (!ahb)
> + return -ENOMEM;
> + ahb->ctx = ahb + 1;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res)
> + return -ENODEV;
> + ahb->regs = devm_request_and_ioremap(&pdev->dev, res);
> + if (!ahb->regs)
> + return -EBUSY;
> +
> + ahb->dev = &pdev->dev;
> + platform_set_drvdata(pdev, ahb);
> + tegra_ahb_gizmo_init(ahb);
> + return 0;
> +}
> +
> +static int __devexit tegra_ahb_remove(struct platform_device *pdev)
> +{
> + platform_set_drvdata(pdev, NULL);
> + return 0;
> +}
> +
> +static const struct of_device_id tegra_ahb_of_match[] __devinitconst = {
> + { .compatible = "nvidia,tegra30-ahb", },
> + { .compatible = "nvidia,tegra20-ahb", },
> + {},
> +};
> +
> +static struct platform_driver tegra_ahb_driver = {
> + .probe = tegra_ahb_probe,
> + .remove = __devexit_p(tegra_ahb_remove),
> + .driver = {
> + .name = DRV_NAME,
> + .owner = THIS_MODULE,
> + .of_match_table = tegra_ahb_of_match,
> + .pm = &tegra_ahb_pm,
> + },
> +};
> +
> +static int __init tegra_ahb_init(void)
> +{
> + return platform_driver_register(&tegra_ahb_driver);
> +}
> +postcore_initcall(tegra_ahb_init);
> +
> +static void __exit tegra_ahb_exit(void)
> +{
> + platform_driver_unregister(&tegra_ahb_driver);
> +}
> +module_exit(tegra_ahb_exit);
> +
> +MODULE_AUTHOR("Hiroshi DOYU <hdoyu@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Tegra AHB driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:" DRV_NAME);
> --
> 1.7.5.4
>
--
balbi
Attachment:
signature.asc
Description: Digital signature
