[PATCH v4 6/8] i2c: tegra: Use relaxed versions of readl/writel

Dmitry Osipenko
2020-01-12T17:17:56Z

There is nothing to synchronize in regards to memory accesses for PIO
transfers and for DMA transfers the DMA API takes care of the syncing.

Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/i2c/busses/i2c-tegra.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index e0eb8f5dcd6b..1a390e1bff72 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -284,12 +284,12 @@ struct tegra_i2c_dev {
static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
unsigned long reg)
{
- writel(val, i2c_dev->base + reg);
+ writel_relaxed(val, i2c_dev->base + reg);
}

static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
{
- return readl(i2c_dev->base + reg);
+ return readl_relaxed(i2c_dev->base + reg);
}

/*
@@ -307,16 +307,16 @@ static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev,
static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
unsigned long reg)
{
- writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
+ writel_relaxed(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));

/* Read back register to make sure that register writes completed */
if (reg != I2C_TX_FIFO)
- readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
+ readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
}

static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
{
- return readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
+ return readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
}

static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data,
@@ -689,12 +689,13 @@ static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev)
i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD);

if (i2c_dev->is_curr_atomic_xfer)
- err = readl_poll_timeout_atomic(addr, val, val == 0,
- 1000,
- I2C_CONFIG_LOAD_TIMEOUT);
+ err = readl_relaxed_poll_timeout_atomic(
+ addr, val, val == 0, 1000,
+ I2C_CONFIG_LOAD_TIMEOUT);
else
- err = readl_poll_timeout(addr, val, val == 0, 1000,
- I2C_CONFIG_LOAD_TIMEOUT);
+ err = readl_relaxed_poll_timeout(
+ addr, val, val == 0, 1000,
+ I2C_CONFIG_LOAD_TIMEOUT);

if (err) {
dev_warn(i2c_dev->dev,
--
2.24.0