Messages in this thread | | | Date | Thu, 3 Oct 2013 16:02:02 -0300 | From | Ezequiel Garcia <> | Subject | Re: [PATCH v2 1/2] ARM: kirkwood: retain MAC address for DT ethernet |
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On Thu, Oct 03, 2013 at 08:56:08PM +0200, Sebastian Hesselbarth wrote: > Ethernet IP on Kirkwood SoCs loose their MAC address register content > if clock gated. To allow modular ethernet driver setups and gated clocks > also on non-DT capable bootloaders, we fixup port device nodes with no > valid MAC address property. This patch copies MAC address register > contents set up by bootloaders early, notably before ethernet clocks > are gated. While at it, also reorder call sequence in _dt_init. > > Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> > --- > Changelog: > v1->v2: > - check for gated clock before accessing eth registers > (Suggested by Andrew Lunn) > > TBH, as there is no "official" clk_is_enabled but just the __clk_is_enabled > one, this is close to abuse of CCF API. Actually, there should either be an > clk_is_enabled or we enable the clock, copy a possible invalid MAC address > and disable the clock again. (Added Mike, who might have an opinion about > clk_is_enabled) > > Cc: Jason Cooper <jason@lakedaemon.net> > Cc: Andrew Lunn <andrew@lunn.ch> > Cc: Russell King <linux@arm.linux.org.uk> > Cc: Grant Likely <grant.likely@linaro.org> > Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> > Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> > Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> > Cc: Mike Turquette <mturquette@linaro.org> > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > --- > arch/arm/mach-kirkwood/board-dt.c | 77 +++++++++++++++++++++++++++++++++++-- > 1 file changed, 74 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-kirkwood/board-dt.c b/arch/arm/mach-kirkwood/board-dt.c > index 82d3ad8..f5f35bb 100644 > --- a/arch/arm/mach-kirkwood/board-dt.c > +++ b/arch/arm/mach-kirkwood/board-dt.c > @@ -13,6 +13,8 @@ > #include <linux/kernel.h> > #include <linux/init.h> > #include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_net.h> > #include <linux/of_platform.h> > #include <linux/clk-provider.h> > #include <linux/clocksource.h> > @@ -66,6 +68,76 @@ static void __init kirkwood_legacy_clk_init(void) > clk_prepare_enable(clk); > } > > +#define MV643XX_ETH_MAC_ADDR_LOW 0x0414 > +#define MV643XX_ETH_MAC_ADDR_HIGH 0x0418 > + > +static void __init kirkwood_dt_eth_fixup(void) > +{ > + struct device_node *np; > + > + /* > + * The ethernet interfaces forget the MAC address assigned by u-boot > + * if the clocks are turned off. Usually, u-boot on kirkwood boards > + * has no DT support to properly set local-mac-address property. > + * As a workaround, we get the MAC address from mv643xx_eth registers > + * and update the port device node if no valid MAC address is set. > + */ > + for_each_compatible_node(np, NULL, "marvell,kirkwood-eth-port") { > + struct device_node *pnp = of_get_parent(np); > + struct clk *clk; > + struct property *pmac; > + void __iomem *io; > + u8 *macaddr; > + u32 reg; > + > + if (!pnp || !of_device_is_available(pnp)) > + continue; > + > + clk = of_clk_get(pnp, 0); > + if (!__clk_is_enabled(clk) || of_get_mac_address(np)) {
Mm.. just as you say this usage of __clk_is_enabled is awkard to say the least.
I'm wondering: is the clock really disabled if the device is not available (i.e. status == 'ok')? In other words: isn't the !of_device_is_available() test enough?
Or maybe I'm missing something? -- Ezequiel García, Free Electrons Embedded Linux, Kernel and Android Engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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