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2018-03-09imx: syscounter: make sure asm is volatileYasushi SHOJI
Without the volatile attribute, compilers are entitled to optimize out the same asm(). In the case of __udelay() in syscounter.c, it calls `get_ticks()` twice, one for the starting time and the second in the loop to check the current time. When compilers inline `get_ticks()` they see the same `mrrc` instructions and optimize out the second one. This leads to infinite loop since we don't get updated value from the system counter. Here is a portion of the disassembly of __udelay: 88: 428b cmp r3, r1 8a: f8ce 20a4 str.w r2, [lr, #164] ; 0xa4 8e: bf08 it eq 90: 4282 cmpeq r2, r0 92: f8ce 30a0 str.w r3, [lr, #160] ; 0xa0 96: d3f7 bcc.n 88 <__udelay+0x88> 98: e8bd 8cf0 ldmia.w sp!, {r4, r5, r6, r7, sl, fp, pc} Note that final jump / loop at 96 to 88, we don't have any `mrrc`. With a volatile attribute, the above changes to this: 8a: ec53 2f0e mrrc 15, 0, r2, r3, cr14 8e: 42ab cmp r3, r5 90: f8c1 20a4 str.w r2, [r1, #164] ; 0xa4 94: bf08 it eq 96: 42a2 cmpeq r2, r4 98: f8c1 30a0 str.w r3, [r1, #160] ; 0xa0 9c: d3f5 bcc.n 8a <__udelay+0x8a> 9e: e8bd 8cf0 ldmia.w sp!, {r4, r5, r6, r7, sl, fp, pc} a2: bf00 nop I'm advised[1] to put volatile on all asm(), so this commit also adds it to the asm() in timer_init(). [1]: https://lists.denx.de/pipermail/u-boot/2018-March/322062.html Signed-off-by: Yasushi SHOJI <yasushi.shoji@gmail.com> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
2017-07-12imx: reorganize IMX code as other SOCsStefano Babic
Change is consistent with other SOCs and it is in preparation for adding SOMs. SOC's related files are moved from cpu/ to mach-imx/<SOC>. This change is also coherent with the structure in kernel. Signed-off-by: Stefano Babic <sbabic@denx.de> CC: Fabio Estevam <fabio.estevam@nxp.com> CC: Akshay Bhat <akshaybhat@timesys.com> CC: Ken Lin <Ken.Lin@advantech.com.tw> CC: Marek Vasut <marek.vasut@gmail.com> CC: Heiko Schocher <hs@denx.de> CC: "Sébastien Szymanski" <sebastien.szymanski@armadeus.com> CC: Christian Gmeiner <christian.gmeiner@gmail.com> CC: Stefan Roese <sr@denx.de> CC: Patrick Bruenn <p.bruenn@beckhoff.com> CC: Troy Kisky <troy.kisky@boundarydevices.com> CC: Nikita Kiryanov <nikita@compulab.co.il> CC: Otavio Salvador <otavio@ossystems.com.br> CC: "Eric Bénard" <eric@eukrea.com> CC: Jagan Teki <jagan@amarulasolutions.com> CC: Ye Li <ye.li@nxp.com> CC: Peng Fan <peng.fan@nxp.com> CC: Adrian Alonso <adrian.alonso@nxp.com> CC: Alison Wang <b18965@freescale.com> CC: Tim Harvey <tharvey@gateworks.com> CC: Martin Donnelly <martin.donnelly@ge.com> CC: Marcin Niestroj <m.niestroj@grinn-global.com> CC: Lukasz Majewski <lukma@denx.de> CC: Adam Ford <aford173@gmail.com> CC: "Albert ARIBAUD (3ADEV)" <albert.aribaud@3adev.fr> CC: Boris Brezillon <boris.brezillon@free-electrons.com> CC: Soeren Moch <smoch@web.de> CC: Richard Hu <richard.hu@technexion.com> CC: Wig Cheng <wig.cheng@technexion.com> CC: Vanessa Maegima <vanessa.maegima@nxp.com> CC: Max Krummenacher <max.krummenacher@toradex.com> CC: Stefan Agner <stefan.agner@toradex.com> CC: Markus Niebel <Markus.Niebel@tq-group.com> CC: Breno Lima <breno.lima@nxp.com> CC: Francesco Montefoschi <francesco.montefoschi@udoo.org> CC: Jaehoon Chung <jh80.chung@samsung.com> CC: Scott Wood <oss@buserror.net> CC: Joe Hershberger <joe.hershberger@ni.com> CC: Anatolij Gustschin <agust@denx.de> CC: Simon Glass <sjg@chromium.org> CC: "Andrew F. Davis" <afd@ti.com> CC: "Łukasz Majewski" <l.majewski@samsung.com> CC: Patrice Chotard <patrice.chotard@st.com> CC: Nobuhiro Iwamatsu <iwamatsu@nigauri.org> CC: Hans de Goede <hdegoede@redhat.com> CC: Masahiro Yamada <yamada.masahiro@socionext.com> CC: Stephen Warren <swarren@nvidia.com> CC: Andre Przywara <andre.przywara@arm.com> CC: "Álvaro Fernández Rojas" <noltari@gmail.com> CC: York Sun <york.sun@nxp.com> CC: Xiaoliang Yang <xiaoliang.yang@nxp.com> CC: Chen-Yu Tsai <wens@csie.org> CC: George McCollister <george.mccollister@gmail.com> CC: Sven Ebenfeld <sven.ebenfeld@gmail.com> CC: Filip Brozovic <fbrozovic@gmail.com> CC: Petr Kulhavy <brain@jikos.cz> CC: Eric Nelson <eric@nelint.com> CC: Bai Ping <ping.bai@nxp.com> CC: Anson Huang <Anson.Huang@nxp.com> CC: Sanchayan Maity <maitysanchayan@gmail.com> CC: Lokesh Vutla <lokeshvutla@ti.com> CC: Patrick Delaunay <patrick.delaunay@st.com> CC: Gary Bisson <gary.bisson@boundarydevices.com> CC: Alexander Graf <agraf@suse.de> CC: u-boot@lists.denx.de Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com> Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>