[PATCH v2 14/20] mips: Use offset-sized IO-mem accessors in CPS debug printout

From: <Sergey.Semin@baikalelectronics.ru>
To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Serge Semin <Sergey.Semin@baikalelectronics.ru>,
	Serge Semin <fancer.lancer@gmail.com>,
	Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>,
	Paul Burton <paulburton@kernel.org>,
	Ralf Baechle <ralf@linux-mips.org>, Arnd Bergmann <arnd@arndb.de>,
	Rob Herring <robh+dt@kernel.org>, <linux-pm@vger.kernel.org>,
	<devicetree@vger.kernel.org>,
	Allison Randal <allison@lohutok.net>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	<linux-mips@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v2 14/20] mips: Use offset-sized IO-mem accessors in CPS debug printout
Date: Wed, 6 May 2020 20:42:32 +0300	[thread overview]
Message-ID: <20200506174238.15385-15-Sergey.Semin@baikalelectronics.ru> (raw)
In-Reply-To: <20200506174238.15385-1-Sergey.Semin@baikalelectronics.ru>

From: Serge Semin <Sergey.Semin@baikalelectronics.ru>

Similar to commit 8e5c62e38a88 ("mips: early_printk_8250: Use offset-sized
IO-mem accessors") the IO-memory might require to use a proper load/store
instructions (like Bailal-T1 IO-memory). To fix the cps-vec UART debug
printout lets use the memory access instructions in accordance with the
UART registers offset config specified at boot time.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-pm@vger.kernel.org
Cc: devicetree@vger.kernel.org

---
There might be another problem in cps-vec-ns16550.S connected with the
difference in CPU/devices endinanness on some platforms. But there is
no such for Baikal-T1 SoC.
---
 arch/mips/kernel/cps-vec-ns16550.S | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/mips/kernel/cps-vec-ns16550.S b/arch/mips/kernel/cps-vec-ns16550.S
index d5a67b4ce9f6..2adb1c56c7c5 100644
--- a/arch/mips/kernel/cps-vec-ns16550.S
+++ b/arch/mips/kernel/cps-vec-ns16550.S
@@ -14,16 +14,30 @@
 #define UART_TX_OFS	(UART_TX << CONFIG_MIPS_CPS_NS16550_SHIFT)
 #define UART_LSR_OFS	(UART_LSR << CONFIG_MIPS_CPS_NS16550_SHIFT)
 
+#if CONFIG_MIPS_CPS_NS16550_SHIFT == 0
+# define UART_L		lb
+# define UART_S		sb
+#elif CONFIG_MIPS_CPS_NS16550_SHIFT == 1
+# define UART_L		lh
+# define UART_S		sh
+#elif CONFIG_MIPS_CPS_NS16550_SHIFT == 2
+# define UART_L		lw
+# define UART_S		sw
+#else
+# define UART_L		lw
+# define UART_S		sb
+#endif
+
 /**
  * _mips_cps_putc() - write a character to the UART
  * @a0: ASCII character to write
  * @t9: UART base address
  */
 LEAF(_mips_cps_putc)
-1:	lw		t0, UART_LSR_OFS(t9)
+1:	UART_L		t0, UART_LSR_OFS(t9)
 	andi		t0, t0, UART_LSR_TEMT
 	beqz		t0, 1b
-	sb		a0, UART_TX_OFS(t9)
+	UART_S		a0, UART_TX_OFS(t9)
 	jr		ra
 	END(_mips_cps_putc)
 
-- 
2.25.1

