According to the Aspeed specification, the reset and enable sequence
should be done when the clock is stopped. The specification doesn't
define behavior if the reset is done while the clock is enabled.
From testing on the AST2500, the LPC Controller has problems if the
clock is reset while enabled.
Therefore, check whether the clock is enabled or not before performing
the reset and enable sequence in the Aspeed clock driver.
Reported-by: Lei Yu <mine260309@gmail.com>
Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Fixes: 15ed8ce5f8 ("clk: aspeed: Register gated clocks")
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Some of the Aspeed clocks are disabled by setting the relevant bit in
the "clock stop control" register to one, while others are disabled by
setting their bit to zero. The driver already uses a flag per gate to
identify this behavior, but doesn't apply it in the clock is_enabled
function.
Use the existing gate flag to correctly return whether or not a clock
is enabled in the aspeed_clk_is_enabled function.
Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Fixes: 6671507f0f ("clk: aspeed: Handle inverse polarity of USB port 1 clock gate")
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The USB port 1 clock gate control has an inversed polarity
from all the other clock gates in the chip. This makes the
aspeed_clk_{enable,disable} functions honor the flag
CLK_GATE_SET_TO_DISABLE and set that flag appropriately
so it's set for all clocks except USB port 1.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
In case of error, the function of_iomap() returns NULL pointer not
ERR_PTR(). The IS_ERR() test in the return value check should be
replaced with NULL test.
Fixes: a2e230c7b2ea ("clk: Add clock driver for ASPEED BMC SoCs")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
There are some resets that are not associated with gates. These are
represented by a reset controller.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The majority of the clocks in the system are gates paired with a reset
controller that holds the IP in reset.
This borrows from clk_hw_register_gate, but registers two 'gates', one
to control the clock enable register and the other to control the reset
IP. This allows us to enforce the ordering:
1. Place IP in reset
2. Enable clock
3. Delay
4. Release reset
There are some gates that do not have an associated reset; these are
handled by using -1 as the index for the reset.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This registers a platform driver to set up all of the non-core clocks.
The clocks that have configurable rates are now registered.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This registers the core clocks; those which are required to calculate
the rate of the timer peripheral so the system can load a clocksource
driver.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This adds the stub of a driver for the ASPEED SoCs. The clocks are
defined and the static registration is set up.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
