M_CTXPRS_BLK
phyctl = brcms_b_read_shm(wlc_hw, M_CTXPRS_BLK + C_CTX_PCTLWD_POS);
brcms_b_write_shm(wlc_hw, M_CTXPRS_BLK + C_CTX_PCTLWD_POS, phyctl);