powerpc/mpc85xx: Remove some dead code
authorScott Wood <scottwood@freescale.com>
Wed, 8 Apr 2015 01:20:01 +0000 (20:20 -0500)
committerYork Sun <yorksun@freescale.com>
Mon, 20 Apr 2015 17:15:29 +0000 (10:15 -0700)
U-Boot does not have system calls (the services it exposes to
standalone commands use a different mechanism), so the syscall handler
is dead code.  It's also broken code, as it assumes it is located at
0xc00 -- while even before the patch to stop relocating exception
vectors to 0, U-Boot had the syscall at 0x900.

The critical and machine check return paths are never called -- the
regular exception return path is used instead, which works because
xSRR0/1 have already been saved and can be restored via the regular
SRR0/1 (we don't care too much in U-Boot about taking a critical/mcheck
inside another exception prolog/epilog).

Also remove a few other small unused functions.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
arch/powerpc/cpu/mpc85xx/start.S
include/common.h

index 61883cb05080701b255f15d07736b12326663e1a..28f04eefabb86e959e7ec113d9f10587446ab2e8 100644 (file)
@@ -1201,73 +1201,7 @@ ProgramCheck:
        /* No FPU on MPC85xx.  This exception is not supposed to happen.
        */
        STD_EXCEPTION(0x0800, FPUnavailable, UnknownException)
-
-/*
- * r0 - SYSCALL number
- * r3-... arguments
- */
-SystemCall:
-       addis   r11,r0,0        /* get functions table addr */
-       ori     r11,r11,0       /* Note: this code is patched in trap_init */
-       addis   r12,r0,0        /* get number of functions */
-       ori     r12,r12,0
-
-       cmplw   0,r0,r12
-       bge     1f
-
-       rlwinm  r0,r0,2,0,31    /* fn_addr = fn_tbl[r0] */
-       add     r11,r11,r0
-       lwz     r11,0(r11)
-
-       li      r20,0xd00-4     /* Get stack pointer */
-       lwz     r12,0(r20)
-       subi    r12,r12,12      /* Adjust stack pointer */
-       li      r0,0xc00+_end_back-SystemCall
-       cmplw   0,r0,r12        /* Check stack overflow */
-       bgt     1f
-       stw     r12,0(r20)
-
-       mflr    r0
-       stw     r0,0(r12)
-       mfspr   r0,SRR0
-       stw     r0,4(r12)
-       mfspr   r0,SRR1
-       stw     r0,8(r12)
-
-       li      r12,0xc00+_back-SystemCall
-       mtlr    r12
-       mtspr   SRR0,r11
-
-1:     SYNC
-       rfi
-_back:
-
-       mfmsr   r11                     /* Disable interrupts */
-       li      r12,0
-       ori     r12,r12,MSR_EE
-       andc    r11,r11,r12
-       SYNC                            /* Some chip revs need this... */
-       mtmsr   r11
-       SYNC
-
-       li      r12,0xd00-4             /* restore regs */
-       lwz     r12,0(r12)
-
-       lwz     r11,0(r12)
-       mtlr    r11
-       lwz     r11,4(r12)
-       mtspr   SRR0,r11
-       lwz     r11,8(r12)
-       mtspr   SRR1,r11
-
-       addi    r12,r12,12              /* Adjust stack pointer */
-       li      r20,0xd00-4
-       stw     r12,0(r20)
-
-       SYNC
-       rfi
-_end_back:
-
+       STD_EXCEPTION(0x0900, SystemCall, UnknownException)
        STD_EXCEPTION(0x0a00, Decrementer, timer_interrupt)
        STD_EXCEPTION(0x0b00, IntervalTimer, UnknownException)
        STD_EXCEPTION(0x0c00, WatchdogTimer, UnknownException)
@@ -1334,66 +1268,6 @@ int_return:
        SYNC
        rfi
 
-crit_return:
-       mfmsr   r28             /* Disable interrupts */
-       li      r4,0
-       ori     r4,r4,MSR_EE
-       andc    r28,r28,r4
-       SYNC                    /* Some chip revs need this... */
-       mtmsr   r28
-       SYNC
-       lwz     r2,_CTR(r1)
-       lwz     r0,_LINK(r1)
-       mtctr   r2
-       mtlr    r0
-       lwz     r2,_XER(r1)
-       lwz     r0,_CCR(r1)
-       mtspr   XER,r2
-       mtcrf   0xFF,r0
-       REST_10GPRS(3, r1)
-       REST_10GPRS(13, r1)
-       REST_8GPRS(23, r1)
-       REST_GPR(31, r1)
-       lwz     r2,_NIP(r1)     /* Restore environment */
-       lwz     r0,_MSR(r1)
-       mtspr   SPRN_CSRR0,r2
-       mtspr   SPRN_CSRR1,r0
-       lwz     r0,GPR0(r1)
-       lwz     r2,GPR2(r1)
-       lwz     r1,GPR1(r1)
-       SYNC
-       rfci
-
-mck_return:
-       mfmsr   r28             /* Disable interrupts */
-       li      r4,0
-       ori     r4,r4,MSR_EE
-       andc    r28,r28,r4
-       SYNC                    /* Some chip revs need this... */
-       mtmsr   r28
-       SYNC
-       lwz     r2,_CTR(r1)
-       lwz     r0,_LINK(r1)
-       mtctr   r2
-       mtlr    r0
-       lwz     r2,_XER(r1)
-       lwz     r0,_CCR(r1)
-       mtspr   XER,r2
-       mtcrf   0xFF,r0
-       REST_10GPRS(3, r1)
-       REST_10GPRS(13, r1)
-       REST_8GPRS(23, r1)
-       REST_GPR(31, r1)
-       lwz     r2,_NIP(r1)     /* Restore environment */
-       lwz     r0,_MSR(r1)
-       mtspr   SPRN_MCSRR0,r2
-       mtspr   SPRN_MCSRR1,r0
-       lwz     r0,GPR0(r1)
-       lwz     r2,GPR2(r1)
-       lwz     r1,GPR1(r1)
-       SYNC
-       rfmci
-
 /* Cache functions.
 */
 .globl flush_icache
@@ -1478,11 +1352,6 @@ dcache_status:
        andi.   r3,r3,L1CSR0_DCE
        blr
 
-       .globl get_pir
-get_pir:
-       mfspr   r3,PIR
-       blr
-
        .globl get_pvr
 get_pvr:
        mfspr   r3,PVR
@@ -1493,11 +1362,6 @@ get_svr:
        mfspr   r3,SVR
        blr
 
-       .globl wr_tcr
-wr_tcr:
-       mtspr   TCR,r3
-       blr
-
 /*------------------------------------------------------------------------------- */
 /* Function:    in8 */
 /* Description:         Input 8 bits */
index a079f13bdc1e55e31f3d0f68cb57cf1dc9de1423..f57055043840055170153691108b4080173b788f 100644 (file)
@@ -482,7 +482,6 @@ int testdram(void);
     defined(CONFIG_8xx)
 uint   get_immr      (uint);
 #endif
-uint   get_pir       (void);
 #if defined(CONFIG_MPC5xxx)
 uint   get_svr       (void);
 #endif