alistair23-linux/drivers/amba/tegra-ahb.c
Paul Walmsley ce7a10b0ff ARM: 8334/1: amba: tegra-ahb: detect and correct bogus base address
amba: tegra-ahb: detect and correct bogus base address

From a hardware SoC integration point of view, the starting address of
this IP block in the existing Tegra SoC DT files is off by 4 bytes
from the actual base address.  Since we attempt to make old DT files
forward-compatible with newer kernels, we cannot fix the IP block base
address in old DT data. This patch works around the problem by
detecting the four byte base address offset in the driver code, and
correcting it if it's detected.  (In general, IP block base addresses
almost always have a null low byte.)

Future SoC DT data for Tegra AHB should use the correct Tegra AHB base
address, in cases where there is no DT data backward compatibility
requirement.

This patch is a revision of the patch originally titled
"amba: tegra-ahb: use correct base address for future chip support".
This revision implements changes requested by Russell King:

http://marc.info/?l=linux-tegra&m=142658851825062&w=2
http://marc.info/?l=linux-tegra&m=142658873925178&w=2

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Paul Walmsley <pwalmsley@nvidia.com>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Hiroshi DOYU <hdoyu@nvidia.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-kernel@vger.kernel.org
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-02 10:03:55 +01:00

310 lines
8.1 KiB
C

/*
* Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
* Copyright (C) 2011 Google, Inc.
*
* Author:
* Jay Cheng <jacheng@nvidia.com>
* James Wylder <james.wylder@motorola.com>
* Benoit Goby <benoit@android.com>
* Colin Cross <ccross@android.com>
* Hiroshi DOYU <hdoyu@nvidia.com>
*
* 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/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/of.h>
#include <soc/tegra/ahb.h>
#define DRV_NAME "tegra-ahb"
#define AHB_ARBITRATION_DISABLE 0x04
#define AHB_ARBITRATION_PRIORITY_CTRL 0x08
#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 0x10
#define ENB_FAST_REARBITRATE BIT(2)
#define DONT_SPLIT_AHB_WR BIT(7)
#define AHB_GIZMO_APB_DMA 0x14
#define AHB_GIZMO_IDE 0x1c
#define AHB_GIZMO_USB 0x20
#define AHB_GIZMO_AHB_XBAR_BRIDGE 0x24
#define AHB_GIZMO_CPU_AHB_BRIDGE 0x28
#define AHB_GIZMO_COP_AHB_BRIDGE 0x2c
#define AHB_GIZMO_XBAR_APB_CTLR 0x30
#define AHB_GIZMO_VCP_AHB_BRIDGE 0x34
#define AHB_GIZMO_NAND 0x40
#define AHB_GIZMO_SDMMC4 0x48
#define AHB_GIZMO_XIO 0x4c
#define AHB_GIZMO_BSEV 0x64
#define AHB_GIZMO_BSEA 0x74
#define AHB_GIZMO_NOR 0x78
#define AHB_GIZMO_USB2 0x7c
#define AHB_GIZMO_USB3 0x80
#define IMMEDIATE BIT(18)
#define AHB_GIZMO_SDMMC1 0x84
#define AHB_GIZMO_SDMMC2 0x88
#define AHB_GIZMO_SDMMC3 0x8c
#define AHB_MEM_PREFETCH_CFG_X 0xdc
#define AHB_ARBITRATION_XBAR_CTRL 0xe0
#define AHB_MEM_PREFETCH_CFG3 0xe4
#define AHB_MEM_PREFETCH_CFG4 0xe8
#define AHB_MEM_PREFETCH_CFG1 0xf0
#define AHB_MEM_PREFETCH_CFG2 0xf4
#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 0xfc
#define AHB_ARBITRATION_XBAR_CTRL_SMMU_INIT_DONE BIT(17)
/*
* INCORRECT_BASE_ADDR_LOW_BYTE: Legacy kernel DT files for Tegra SoCs
* prior to Tegra124 generally use a physical base address ending in
* 0x4 for the AHB IP block. According to the TRM, the low byte
* should be 0x0. During device probing, this macro is used to detect
* whether the passed-in physical address is incorrect, and if so, to
* correct it.
*/
#define INCORRECT_BASE_ADDR_LOW_BYTE 0x4
static struct platform_driver tegra_ahb_driver;
static const 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;
struct device *dev;
u32 ctx[0];
};
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);
}
#ifdef CONFIG_TEGRA_IOMMU_SMMU
static int tegra_ahb_match_by_smmu(struct device *dev, void *data)
{
struct tegra_ahb *ahb = dev_get_drvdata(dev);
struct device_node *dn = data;
return (ahb->dev->of_node == dn) ? 1 : 0;
}
int tegra_ahb_enable_smmu(struct device_node *dn)
{
struct device *dev;
u32 val;
struct tegra_ahb *ahb;
dev = driver_find_device(&tegra_ahb_driver.driver, NULL, dn,
tegra_ahb_match_by_smmu);
if (!dev)
return -EPROBE_DEFER;
ahb = dev_get_drvdata(dev);
val = gizmo_readl(ahb, AHB_ARBITRATION_XBAR_CTRL);
val |= AHB_ARBITRATION_XBAR_CTRL_SMMU_INIT_DONE;
gizmo_writel(ahb, val, AHB_ARBITRATION_XBAR_CTRL);
return 0;
}
EXPORT_SYMBOL(tegra_ahb_enable_smmu);
#endif
#ifdef CONFIG_PM
static int tegra_ahb_suspend(struct device *dev)
{
int i;
struct tegra_ahb *ahb = dev_get_drvdata(dev);
for (i = 0; i < ARRAY_SIZE(tegra_ahb_gizmo); i++)
ahb->ctx[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);
for (i = 0; i < ARRAY_SIZE(tegra_ahb_gizmo); i++)
gizmo_writel(ahb, ahb->ctx[i], tegra_ahb_gizmo[i]);
return 0;
}
#endif
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 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;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
/* Correct the IP block base address if necessary */
if (res &&
(res->start & INCORRECT_BASE_ADDR_LOW_BYTE) ==
INCORRECT_BASE_ADDR_LOW_BYTE) {
dev_warn(&pdev->dev, "incorrect AHB base address in DT data - enabling workaround\n");
res->start -= INCORRECT_BASE_ADDR_LOW_BYTE;
}
ahb->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(ahb->regs))
return PTR_ERR(ahb->regs);
ahb->dev = &pdev->dev;
platform_set_drvdata(pdev, ahb);
tegra_ahb_gizmo_init(ahb);
return 0;
}
static const struct of_device_id tegra_ahb_of_match[] = {
{ .compatible = "nvidia,tegra30-ahb", },
{ .compatible = "nvidia,tegra20-ahb", },
{},
};
static struct platform_driver tegra_ahb_driver = {
.probe = tegra_ahb_probe,
.driver = {
.name = DRV_NAME,
.of_match_table = tegra_ahb_of_match,
.pm = &tegra_ahb_pm,
},
};
module_platform_driver(tegra_ahb_driver);
MODULE_AUTHOR("Hiroshi DOYU <hdoyu@nvidia.com>");
MODULE_DESCRIPTION("Tegra AHB driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DRV_NAME);