powerpc, 8xx: Implement GLL2 ERRATA
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Wolfgang Denk <wd@denx.de>
Reviewed-by: Heiko Schocher <hs@denx.de>
diff --git a/arch/powerpc/cpu/mpc8xx/cpu_init.c b/arch/powerpc/cpu/mpc8xx/cpu_init.c
index cf12809..a51596a 100644
--- a/arch/powerpc/cpu/mpc8xx/cpu_init.c
+++ b/arch/powerpc/cpu/mpc8xx/cpu_init.c
@@ -51,6 +51,26 @@
clrsetbits_be32(&immr->im_clkrst.car_sccr, ~SCCR_MASK,
CONFIG_SYS_SCCR);
+ /*
+ * MPC866/885 ERRATA GLL2
+ * Description:
+ * In 1:2:1 mode, when HRESET is detected at the positive edge of
+ * EXTCLK, then there will be a loss of phase between
+ * EXTCLK and CLKOUT.
+ *
+ * Workaround:
+ * Reprogram the SCCR:
+ * 1. Write 1'b00 to SCCR[EBDF].
+ * 2. Write 1'b01 to SCCR[EBDF].
+ * 3. Rewrite the desired value to the PLPRCR register.
+ */
+ reg = in_be32(&immr->im_clkrst.car_sccr);
+ /* Are we in mode 1:2:1 ? */
+ if ((reg & SCCR_EBDF11) == SCCR_EBDF01) {
+ clrbits_be32(&immr->im_clkrst.car_sccr, SCCR_EBDF11);
+ setbits_be32(&immr->im_clkrst.car_sccr, SCCR_EBDF01);
+ }
+
/* PLL (CPU clock) settings (15-30) */
out_be32(&immr->im_clkrstk.cark_plprcrk, KAPWR_KEY);