> On Thu, 3 Oct 2024 18:52:24 +0530
> <pbhagavat...@marvell.com> wrote:
>
> > +static __rte_always_inline uint16_t
> > +cn20k_sso_hws_get_work(struct cn20k_sso_hws *ws, struct rte_event
> *ev, const uint32_t flags)
> > +{
> > + union {
> > + __uint128_t get_work;
> > + uint64_t u64[2];
> > + } gw;
> > +
> > + gw.get_work = ws->gw_wdata;
> > +#if defined(RTE_ARCH_ARM64)
> > +#if defined(__clang__)
> > + register uint64_t x0 __asm("x0") = (uint64_t)gw.u64[0];
> > + register uint64_t x1 __asm("x1") = (uint64_t)gw.u64[1];
> > +#if defined(RTE_ARM_USE_WFE)
> > + plt_write64(gw.u64[0], ws->base +
> SSOW_LF_GWS_OP_GET_WORK0);
> > + asm volatile(PLT_CPU_FEATURE_PREAMBLE
> > + " ldp %[x0], %[x1], [%[tag_loc]] \n"
> > + " tbz %[x0], %[pend_gw], done%= \n"
> > + " sevl \n"
> > + "rty%=: wfe \n"
> > + " ldp %[x0], %[x1], [%[tag_loc]] \n"
> > + " tbnz %[x0], %[pend_gw], rty%= \n"
> > + "done%=: \n"
> > + " dmb ld \n"
> > + : [x0] "+r" (x0), [x1] "+r" (x1)
> > + : [tag_loc] "r"(ws->base + SSOW_LF_GWS_WQE0),
> > + [pend_gw]
> "i"(SSOW_LF_GWS_TAG_PEND_GET_WORK_BIT)
> > + : "memory");
> > +#else
> > + asm volatile(".arch armv8-a+lse\n"
> > + "caspal %[x0], %[x1], %[x0], %[x1], [%[dst]]\n"
> > + : [x0] "+r" (x0), [x1] "+r" (x1)
> > + : [dst] "r"(ws->base + SSOW_LF_GWS_OP_GET_WORK0)
> > + : "memory");
> > +#endif
> > + gw.u64[0] = x0;
> > + gw.u64[1] = x1;
> > +#else
> > +#if defined(RTE_ARM_USE_WFE)
> > + plt_write64(gw.u64[0], ws->base +
> SSOW_LF_GWS_OP_GET_WORK0);
> > + asm volatile(PLT_CPU_FEATURE_PREAMBLE
> > + " ldp %[wdata], %H[wdata], [%[tag_loc]] \n"
> > + " tbz %[wdata], %[pend_gw], done%= \n"
> > + " sevl \n"
> > + "rty%=: wfe \n"
> > + " ldp %[wdata], %H[wdata], [%[tag_loc]] \n"
> > + " tbnz %[wdata], %[pend_gw], rty%= \n"
> > + "done%=: \n"
> > + " dmb ld \n"
> > + : [wdata] "=&r"(gw.get_work)
> > + : [tag_loc] "r"(ws->base + SSOW_LF_GWS_WQE0),
> > + [pend_gw]
> "i"(SSOW_LF_GWS_TAG_PEND_GET_WORK_BIT)
> > + : "memory");
> > +#else
> > + asm volatile(PLT_CPU_FEATURE_PREAMBLE
> > + "caspal %[wdata], %H[wdata], %[wdata], %H[wdata],
> [%[gw_loc]]\n"
> > + : [wdata] "+r"(gw.get_work)
> > + : [gw_loc] "r"(ws->base +
> SSOW_LF_GWS_OP_GET_WORK0)
> > + : "memory");
> > +#endif
> > +#endif
>
> This generates lots of warnings like:
>
> WARNING:QUOTED_WHITESPACE_BEFORE_NEWLINE: unnecessary
> whitespace before a quoted newline
> #131: FILE: drivers/event/cnxk/cn20k_worker.h:39:
> + " ldp %[x0], %[x1], [%[tag_loc]] \n"
>
> But the bigger problem is burying assembly in a driver is a bad idea.
> The use of ARM primitives should be done in EAL, not down in the PMD.
This sequence is very specific to the SSO co-processor in CNXK.
I don’t think we can move it to EAL.
>
