| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <1390952176-30402-2-git-send-email-pdeschrijver@nvidia.com>
Date: Wed, 29 Jan 2014 01:36:11 +0200
From: Peter De Schrijver <pdeschrijver@...dia.com>
To: Peter De Schrijver <pdeschrijver@...dia.com>
CC: <linux-arm-kernel@...ts.infradead.org>,
<linux-tegra@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
Russell King <linux@....linux.org.uk>,
Stephen Warren <swarren@...dotorg.org>,
Thierry Reding <thierry.reding@...il.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Linus Walleij <linus.walleij@...aro.org>,
Wolfram Sang <wsa@...-dreams.de>
Subject: [PATCH v3 1/6] ARM: tegra: export apb dma readl/writel
Export APB DMA readl and writel. These are needed because we can't access
the fuses directly on Tegra20 without potentially causing a system hang.
Also have the APB DMA readl and writel return an error in case of a read
failure instead of just returning zero or ignore write failures.
Signed-off-by: Peter De Schrijver <pdeschrijver@...dia.com>
---
arch/arm/mach-tegra/apbio.c | 51 ++++++++++++++++++++++++++----------------
include/linux/tegra-soc.h | 14 +++++++++++
2 files changed, 45 insertions(+), 20 deletions(-)
diff --git a/arch/arm/mach-tegra/apbio.c b/arch/arm/mach-tegra/apbio.c
index bc47197..e0bf49d 100644
--- a/arch/arm/mach-tegra/apbio.c
+++ b/arch/arm/mach-tegra/apbio.c
@@ -32,8 +32,8 @@ static u32 *tegra_apb_bb;
static dma_addr_t tegra_apb_bb_phys;
static DECLARE_COMPLETION(tegra_apb_wait);
-static u32 tegra_apb_readl_direct(unsigned long offset);
-static void tegra_apb_writel_direct(u32 value, unsigned long offset);
+static int tegra_apb_readl_direct(unsigned long offset, u32 *value);
+static int tegra_apb_writel_direct(u32 value, unsigned long offset);
static struct dma_chan *tegra_apb_dma_chan;
static struct dma_slave_config dma_sconfig;
@@ -128,58 +128,64 @@ static int do_dma_transfer(unsigned long apb_add,
return 0;
}
-static u32 tegra_apb_readl_using_dma(unsigned long offset)
+int tegra_apb_readl_using_dma(unsigned long offset, u32 *value)
{
int ret;
if (!tegra_apb_dma_chan && !tegra_apb_dma_init())
- return tegra_apb_readl_direct(offset);
+ return tegra_apb_readl_direct(offset, value);
mutex_lock(&tegra_apb_dma_lock);
ret = do_dma_transfer(offset, DMA_DEV_TO_MEM);
- if (ret < 0) {
+ if (ret < 0)
pr_err("error in reading offset 0x%08lx using dma\n", offset);
- *(u32 *)tegra_apb_bb = 0;
- }
+ else
+ *value = *tegra_apb_bb;
+
mutex_unlock(&tegra_apb_dma_lock);
- return *((u32 *)tegra_apb_bb);
+
+ return ret;
}
-static void tegra_apb_writel_using_dma(u32 value, unsigned long offset)
+int tegra_apb_writel_using_dma(u32 value, unsigned long offset)
{
int ret;
- if (!tegra_apb_dma_chan && !tegra_apb_dma_init()) {
- tegra_apb_writel_direct(value, offset);
- return;
- }
+ if (!tegra_apb_dma_chan && !tegra_apb_dma_init())
+ return tegra_apb_writel_direct(value, offset);
mutex_lock(&tegra_apb_dma_lock);
*((u32 *)tegra_apb_bb) = value;
ret = do_dma_transfer(offset, DMA_MEM_TO_DEV);
+ mutex_unlock(&tegra_apb_dma_lock);
if (ret < 0)
pr_err("error in writing offset 0x%08lx using dma\n", offset);
- mutex_unlock(&tegra_apb_dma_lock);
+
+ return ret;
}
#else
#define tegra_apb_readl_using_dma tegra_apb_readl_direct
#define tegra_apb_writel_using_dma tegra_apb_writel_direct
#endif
-typedef u32 (*apbio_read_fptr)(unsigned long offset);
-typedef void (*apbio_write_fptr)(u32 value, unsigned long offset);
+typedef int (*apbio_read_fptr)(unsigned long offset, u32 *value);
+typedef int (*apbio_write_fptr)(u32 value, unsigned long offset);
static apbio_read_fptr apbio_read;
static apbio_write_fptr apbio_write;
-static u32 tegra_apb_readl_direct(unsigned long offset)
+static int tegra_apb_readl_direct(unsigned long offset, u32 *value)
{
- return readl(IO_ADDRESS(offset));
+ *value = readl(IO_ADDRESS(offset));
+
+ return 0;
}
-static void tegra_apb_writel_direct(u32 value, unsigned long offset)
+static int tegra_apb_writel_direct(u32 value, unsigned long offset)
{
writel(value, IO_ADDRESS(offset));
+
+ return 0;
}
void tegra_apb_io_init(void)
@@ -197,7 +203,12 @@ void tegra_apb_io_init(void)
u32 tegra_apb_readl(unsigned long offset)
{
- return apbio_read(offset);
+ u32 val;
+
+ if (apbio_read(offset, &val) < 0)
+ return 0;
+ else
+ return val;
}
void tegra_apb_writel(u32 value, unsigned long offset)
diff --git a/include/linux/tegra-soc.h b/include/linux/tegra-soc.h
index 95f611d..b02d73b 100644
--- a/include/linux/tegra-soc.h
+++ b/include/linux/tegra-soc.h
@@ -19,4 +19,18 @@
u32 tegra_read_chipid(void);
+
+#if defined(CONFIG_TEGRA20_APB_DMA)
+int tegra_apb_readl_using_dma(unsigned long offset, u32 *value);
+int tegra_apb_writel_using_dma(u32 value, unsigned long offset);
+#else
+static inline int tegra_apb_readl_using_dma(unsigned long offset, u32 *value)
+{
+ return -EINVAL;
+}
+static inline int tegra_apb_writel_using_dma(u32 value, unsigned long offset)
+{
+ return -EINVAL;
+}
+#endif
#endif /* __LINUX_TEGRA_SOC_H_ */
--
1.7.7.rc0.72.g4b5ea.dirty
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists