>From dcd03deec6ec87164f0d5114f6b3b705798c9e00 Mon Sep 17 00:00:00 2001 From: Gerhard Sittig Date: Sat, 9 Nov 2013 21:40:05 +0100 Subject: [PATCH v5 05/17] clk: mpc512x: add backwards compat to the CCF code extend the recently added COMMON_CLK platform support for MPC512x such that it works with incomplete device tree data which lacks clock specs Cc: Mike Turquette Cc: Anatolij Gustschin Cc: linux-arm-kernel@lists.infradead.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Gerhard Sittig --- arch/powerpc/platforms/512x/clock-commonclk.c | 173 ++++++++++++++++++++++++- 1 file changed, 172 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/512x/clock-commonclk.c b/arch/powerpc/platforms/512x/clock-commonclk.c index ddbeaec79246..c1faf3a9ea1f 100644 --- a/arch/powerpc/platforms/512x/clock-commonclk.c +++ b/arch/powerpc/platforms/512x/clock-commonclk.c @@ -11,6 +11,7 @@ * (at your option) any later version. */ +#include #include #include #include @@ -744,7 +745,177 @@ static void mpc5121_clk_provide_migration_support(void) */ static void mpc5121_clk_provide_backwards_compat(void) { - /* TODO */ + enum did_reg_flags { + DID_REG_PSC = BIT(0), + DID_REG_PSCFIFO = BIT(1), + DID_REG_NFC = BIT(2), + DID_REG_CAN = BIT(3), + DID_REG_I2C = BIT(4), + DID_REG_DIU = BIT(5), + DID_REG_VIU = BIT(6), + DID_REG_FEC = BIT(7), + DID_REG_USB = BIT(8), + DID_REG_PATA = BIT(9), + }; + + int did_register; + struct device_node *np; + struct resource res; + int idx; + char devname[32]; + + /* + * those macros are not exactly pretty, but they encapsulate a lot + * of copy'n'paste heavy code which is even more ugly, and reduce + * the potential for inconsistencies in those many code copies + */ + +#define FOR_NODES(compatname) \ + for_each_compatible_node(np, NULL, compatname) + +#define NODE_PREP do { \ + of_address_to_resource(np, 0, &res); \ + snprintf(devname, sizeof(devname), "%08x.%s", res.start, np->name); \ +} while (0) + +#define NODE_CHK(clkname, clkitem, regnode, regflag) do { \ + struct clk *clk; \ + clk = of_clk_get_by_name(np, clkname); \ + if (IS_ERR(clk)) { \ + clk = clkitem; \ + clk_register_clkdev(clk, clkname, devname); \ + if (regnode) \ + clk_register_clkdev(clk, clkname, np->name); \ + did_register |= DID_REG_ ## regflag; \ + pr_debug("clock alias name '%s' for dev '%s' pointer %p\n", \ + clkname, devname, clk); \ + } else { \ + clk_put(clk); \ + } \ +} while (0) + + did_register = 0; + + FOR_NODES(mpc512x_select_psc_compat()) { + NODE_PREP; + idx = (res.start >> 8) & 0xf; + NODE_CHK("ipg", clks[MPC512x_CLK_PSC0 + idx], 0, PSC); + NODE_CHK("mclk", clks[MPC512x_CLK_PSC0_MCLK + idx], 0, PSC); + } + + FOR_NODES("fsl,mpc5121-psc-fifo") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_PSC_FIFO], 1, PSCFIFO); + } + + FOR_NODES("fsl,mpc5121-nfc") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_NFC], 0, NFC); + } + + FOR_NODES("fsl,mpc5121-mscan") { + NODE_PREP; + idx = 0; + idx += (res.start & 0x2000) ? 2 : 0; + idx += (res.start & 0x0080) ? 1 : 0; + NODE_CHK("ipg", clks[MPC512x_CLK_BDLC], 0, CAN); + NODE_CHK("mclk", clks[MPC512x_CLK_MSCAN0_MCLK + idx], 0, CAN); + } + + /* + * do register the 'ips', 'sys', and 'ref' names globally + * instead of inside each individual CAN node, as there is no + * potential for a name conflict (in contrast to 'ipg' and 'mclk') + */ + if (did_register & DID_REG_CAN) { + clk_register_clkdev(clks[MPC512x_CLK_IPS], "ips", NULL); + clk_register_clkdev(clks[MPC512x_CLK_SYS], "sys", NULL); + clk_register_clkdev(clks[MPC512x_CLK_REF], "ref", NULL); + } + + FOR_NODES("fsl,mpc5121-i2c") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_I2C], 0, I2C); + } + + /* + * workaround for the fact that the I2C driver does an "anonymous" + * lookup (NULL name spec, which yields the first clock spec) for + * which we cannot register an alias -- a _global_ 'ipg' alias that + * is not bound to any device name and returns the I2C clock item + * is not a good idea + * + * so we have the lookup in the peripheral driver fail, which is + * silent and non-fatal, and pre-enable the clock item here such + * that register access is possible + * + * see commit b3bfce2b "i2c: mpc: cleanup clock API use" for + * details, adjusting s/NULL/"ipg"/ in i2c-mpc.c would make this + * workaround obsolete + */ + if (did_register & DID_REG_I2C) + clk_prepare_enable(clks[MPC512x_CLK_I2C]); + + FOR_NODES("fsl,mpc5121-diu") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_DIU], 1, DIU); + } + + FOR_NODES("fsl,mpc5121-viu") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_VIU], 0, VIU); + } + + /* + * note that 2771399a "fs_enet: cleanup clock API use" did use the + * "per" string for the clock lookup in contrast to the "ipg" name + * which most other nodes are using -- this is not a fatal thing + * but just something to keep in mind when doing compatibility + * registration, it's a non-issue with up-to-date device tree data + */ + FOR_NODES("fsl,mpc5121-fec") { + NODE_PREP; + NODE_CHK("per", clks[MPC512x_CLK_FEC], 0, FEC); + } + FOR_NODES("fsl,mpc5121-fec-mdio") { + NODE_PREP; + NODE_CHK("per", clks[MPC512x_CLK_FEC], 0, FEC); + } + + FOR_NODES("fsl,mpc5121-usb2-dr") { + NODE_PREP; + idx = (res.start & 0x4000) ? 1 : 0; + NODE_CHK("ipg", clks[MPC512x_CLK_USB1 + idx], 0, USB); + } + + FOR_NODES("fsl,mpc5121-pata") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_PATA], 0, PATA); + } + + /* + * try to collapse diagnostics into a single line of output yet + * provide a full list of what is missing, to avoid noise in the + * absence of up-to-date device tree data -- backwards + * compatibility to old DTBs is a requirement, updates may be + * desirable or preferrable but are not at all mandatory + */ + if (did_register) { + pr_notice("device tree lacks clock specs, adding fallbacks (0x%x,%s%s%s%s%s%s%s%s%s%s)\n", + did_register, + (did_register & DID_REG_PSC) ? " PSC" : "", + (did_register & DID_REG_PSCFIFO) ? " PSCFIFO" : "", + (did_register & DID_REG_NFC) ? " NFC" : "", + (did_register & DID_REG_CAN) ? " CAN" : "", + (did_register & DID_REG_I2C) ? " I2C" : "", + (did_register & DID_REG_DIU) ? " DIU" : "", + (did_register & DID_REG_VIU) ? " VIU" : "", + (did_register & DID_REG_FEC) ? " FEC" : "", + (did_register & DID_REG_USB) ? " USB" : "", + (did_register & DID_REG_PATA) ? " PATA" : ""); + } else { + pr_debug("device tree has clock specs, no fallbacks added\n"); + } } int __init mpc5121_clk_init(void) -- 1.7.10.4