From fddf876a8f56ff53d1354387ebf7fd3997189349 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Thu, 19 Dec 2019 09:46:08 +0000 Subject: [PATCH] mpc83xx_clk: always treat MPC83XX_CLK_PCI as invalid The current mpc83xx_clk driver is broken for any board for which mpc83xx_has_pci() is true, i.e. anything not MPC8308: When is_clk_valid() reports that MPC83XX_CLK_PCI is valid, init_all_clks() proceeds to call init_single_clk(), but that doesn't know about either MPC83XX_CLK_PCI or has any handling of the TYPE_SCCR_ONOFF mode correctly returned by retrieve_mode(). Hence init_single_clk() ends up returning -EINVAL, and the whole board hangs in serial_init(). The quickest fix is to simply pretend that clock is invalid for all, since nobody can have been relying on it. Adding proper support seems to be a bit more involved than just handling TYPE_SCCR_ONOFF: - The power-on-reset value of SCCR[PCICM] is 0, so mpc83xx_clk_enable() would probably need to be tought to enable the clock. - The frequency of PCI_SYNC_OUT is either SYS_CLK_IN or SYS_CLK_IN/2 depending on the CFG_CLKIN_DIV configuration input, but that can't be read from software, so to properly fill out ->speed[MPC83XX_CLK_PCI] I think one would need guidance from Kconfig or dtb. Partially fixes: 07d538d281 clk: Add MPC83xx clock driver Signed-off-by: Rasmus Villemoes Reviewed-by: Mario Six --- drivers/clk/mpc83xx_clk.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/clk/mpc83xx_clk.c b/drivers/clk/mpc83xx_clk.c index cbccda5594..69c6207e49 100644 --- a/drivers/clk/mpc83xx_clk.c +++ b/drivers/clk/mpc83xx_clk.c @@ -66,7 +66,10 @@ static inline bool is_clk_valid(struct udevice *clk, int id) case MPC83XX_CLK_DMAC: return (type == SOC_MPC8308) || (type == SOC_MPC8309); case MPC83XX_CLK_PCI: - return mpc83xx_has_pci(type); + /* + * FIXME: implement proper support for this. + */ + return 0 && mpc83xx_has_pci(type); case MPC83XX_CLK_CSB: return true; case MPC83XX_CLK_I2C2: -- 2.25.1