From: Andrew Lunn Date: Wed, 13 Jun 2012 12:52:45 +0000 (+0200) Subject: ARM: Kirkwood: Fix clk problems modular ethernet driver X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=128789a8293653a4f889f2b1601eea07c00ff65e;p=linux-beck.git ARM: Kirkwood: Fix clk problems modular ethernet driver When the ethernet driver was built as a module, it would lock the machine when loaded. At boot the ethernet clks are unused, so get turned off. Later, when the module is loaded, the probe function would access the hardware before the clock was restarted, and the machine would lock. It has also been determined that when the clk is turned off, the interface forgets its MAC address, which for most systems, is set by the boot loader. When the machine setup file creates a platform device for the interface, prepare and enable the clock for the interface. This will ensure it is not turned off. However, if the setup file only instantiates one platform device, the other will have its clk disabled, thus maybe saving a little power. Report-by: Simon Baatz Signed-off-by: Andrew Lunn Tested-by: Simon Baatz Signed-off-by: Olof Johansson --- diff --git a/arch/arm/mach-kirkwood/common.c b/arch/arm/mach-kirkwood/common.c index 25fb3fd418ef..e1d2c6def5e6 100644 --- a/arch/arm/mach-kirkwood/common.c +++ b/arch/arm/mach-kirkwood/common.c @@ -193,9 +193,11 @@ static struct clk __init *kirkwood_register_gate_fn(const char *name, bit_idx, 0, &gating_lock, fn); } +static struct clk *ge0, *ge1; + void __init kirkwood_clk_init(void) { - struct clk *runit, *ge0, *ge1, *sata0, *sata1, *usb0, *sdio; + struct clk *runit, *sata0, *sata1, *usb0, *sdio; struct clk *crypto, *xor0, *xor1, *pex0, *pex1, *audio; tclk = clk_register_fixed_rate(NULL, "tclk", NULL, @@ -257,6 +259,9 @@ void __init kirkwood_ge00_init(struct mv643xx_eth_platform_data *eth_data) orion_ge00_init(eth_data, GE00_PHYS_BASE, IRQ_KIRKWOOD_GE00_SUM, IRQ_KIRKWOOD_GE00_ERR); + /* The interface forgets the MAC address assigned by u-boot if + the clock is turned off, so claim the clk now. */ + clk_prepare_enable(ge0); } @@ -268,6 +273,7 @@ void __init kirkwood_ge01_init(struct mv643xx_eth_platform_data *eth_data) orion_ge01_init(eth_data, GE01_PHYS_BASE, IRQ_KIRKWOOD_GE01_SUM, IRQ_KIRKWOOD_GE01_ERR); + clk_prepare_enable(ge1); }