Commit 456c3005 authored by Michael Ellerman's avatar Michael Ellerman
Browse files

powerpc/microwatt: Remove unused early debug code 

The original microwatt submission[1] included some early debug code for
using the Microwatt "potato" UART.

The series that was eventually merged switched to using a standard UART,
and so doesn't need any special early debug handling. But some of the
original code was merged accidentally under the non-existent
CONFIG_PPC_EARLY_DEBUG_MICROWATT.

Drop the unused code.

1: https://lore.kernel.org/linuxppc-dev/20200509050340.GD1464954@thinks.paulus.ozlabs.org/



Fixes: 48b545b8 ("powerpc/microwatt: Use standard 16550 UART for console")
Reported-by: default avatarLukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: default avatarAndrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220919052755.800907-1-mpe@ellerman.id.au
parent e74611aa

arch/powerpc/kernel/udbg_16550.c

+0 −39
Original line number Diff line number Diff line
@@ -296,42 +296,3 @@ void __init udbg_init_40x_realmode(void) 
}



#endif /* CONFIG_PPC_EARLY_DEBUG_40x */
 


#ifdef CONFIG_PPC_EARLY_DEBUG_MICROWATT



#define UDBG_UART_MW_ADDR	((void __iomem *)0xc0002000)



static u8 udbg_uart_in_isa300_rm(unsigned int reg)

{

	uint64_t msr = mfmsr();

	uint8_t  c;



	mtmsr(msr & ~(MSR_EE|MSR_DR));

	isync();

	eieio();

	c = __raw_rm_readb(UDBG_UART_MW_ADDR + (reg << 2));

	mtmsr(msr);

	isync();

	return c;

}



static void udbg_uart_out_isa300_rm(unsigned int reg, u8 val)

{

	uint64_t msr = mfmsr();



	mtmsr(msr & ~(MSR_EE|MSR_DR));

	isync();

	eieio();

	__raw_rm_writeb(val, UDBG_UART_MW_ADDR + (reg << 2));

	mtmsr(msr);

	isync();

}



void __init udbg_init_debug_microwatt(void)

{

	udbg_uart_in = udbg_uart_in_isa300_rm;

	udbg_uart_out = udbg_uart_out_isa300_rm;

	udbg_use_uart();

}



#endif /* CONFIG_PPC_EARLY_DEBUG_MICROWATT */