WARNING: This macro do not assume the values for K0DB4, KxDB2, KxFREE, K1RUN, K2RUN and APD bits of CONFIG_SYS_MDREFR_VAL as it was done early on many pxa platforms. All pxa developers that plan to use this macro should check the validity of their MDREFR values.
v1: * strict following to section 6.4.10 of Intel PXA27xx Developer's Manual. * use r7 to store CONFIG_SYS_MDREFR_VAL as r6 is used in pxa_wait_ticks.
v2: * rename pxa_mem_setup macro to pxa2xx_mem_setup * setting of MDREFR[K1RUN] and MDREFR[K2RUN] bits may be optional * skip certain configuration steps if SDRAM is not present/configured * improve/fix comments
Signed-off-by: Mikhail Kshevetskiy mikhail.kshevetskiy@gmail.com --- arch/arm/include/asm/arch-pxa/macro.h | 82 ++++++++++++++++++++++----------- board/vpac270/lowlevel_init.S | 2 +- 2 files changed, 56 insertions(+), 28 deletions(-)
diff --git a/arch/arm/include/asm/arch-pxa/macro.h b/arch/arm/include/asm/arch-pxa/macro.h index 1f1759b..e2ddfe9 100644 --- a/arch/arm/include/asm/arch-pxa/macro.h +++ b/arch/arm/include/asm/arch-pxa/macro.h @@ -102,11 +102,15 @@ /* * This macro sets up the Memory controller of the PXA2xx CPU * - * Clobbered regs: r3, r4, r5 + * Clobbered regs: r3, r4, r5, r6, r7 + * + * See section 6.4.10 of Intel PXA2xx Processor Developer's Manual + * http://www.marvell.com/products/processors/applications/pxa_family/pxa_27x_d... */ -.macro pxa_mem_setup +.macro pxa2xx_mem_setup /* This comes handy when setting MDREFR */ ldr r3, =MEMC_BASE + ldr r7, =CONFIG_SYS_MDREFR_VAL
/* * 1) Initialize Asynchronous static memory controller @@ -149,51 +153,68 @@ */
/* - * Before accessing MDREFR we need a valid DRI field, so we set - * this to power on defaults + DRI field. + * Before accessing MDREFR we need a valid DRI field. + * Also we must properly configure MDREFR[K0DB2] and MDREFR[K0DB4]. + * Optionaly we can set MDREFR[KxFREE] bits. + * So we set MDREFR to power on defaults + (DRI, K0DB2, K0DB4, KxFREE) + * fields from the config. + * + * WARNING: K0DB2 and K0DB4 bits are usually set, while KxFREE bits + * are usually unset. */ ldr r5, [r3, #MDREFR_OFFSET] - bic r5, r5, #0x0ff - bic r5, r5, #0xf00 /* MDREFR user config with zeroed DRI */ - - ldr r4, =CONFIG_SYS_MDREFR_VAL - mov r6, r4 - lsl r4, #20 - lsr r4, #20 /* Get a valid DRI field */ - - orr r5, r5, r4 /* MDREFR user config with correct DRI */ + ldr r4, =( 0xFFF | MDREFR_K0DB4 | MDREFR_K0DB2 | \ + MDREFR_K0FREE | MDREFR_K1FREE | MDREFR_K2FREE ) + bic r5, r5, r4 /* clear DRI, K0DB2, K0DB4, KxFREE fields */ + and r4, r7, r4 + orr r5, r5, r4 /* use custom DRI, K0DB2, K0DB4, KxFREE */
orr r5, #MDREFR_K0RUN orr r5, #MDREFR_SLFRSH bic r5, #MDREFR_APD - bic r5, #MDREFR_E1PIN + + /* enable them later, if SDRAM is present */ + bic r5, #( MDREFR_E1PIN | MDREFR_K1RUN | MDREFR_K2RUN | \ + MDREFR_K1DB2 | MDREFR_K2DB2 )
str r5, [r3, #MDREFR_OFFSET] - ldr r4, [r3, #MDREFR_OFFSET] + ldr r5, [r3, #MDREFR_OFFSET]
/* * 5) Initialize Synchronous Static Memory (Flash/Peripherals) */
- /* Initialize SXCNFG register. Assert the enable bits. - * - * Write SXMRS to cause an MRS command to all enabled banks of - * synchronous static memory. Note that SXLCR need not be written - * at this time. + /* Initialize SXCNFG register to enable synchronous flash memory. + * While the synchronous flash banks are being configured, the SDRAM + * banks must be disabled and MDREFR[APD] must be de-asserted. */ write32rb (MEMC_BASE + SXCNFG_OFFSET), CONFIG_SYS_SXCNFG_VAL
/* - * 6) Initialize SDRAM + * 6) Initialize SDRAM, + * If SDRAM present, then MDREFR[K1RUN] and/or MDREFR[K1RUN] bits + * must be set. Also we must properly configure MDREFR[K1DB2] and + * MDREFR[K2DB2] in this case. + * + * WARNING: K1DB2 and K2DB2 bits are usually set if SDRAM present */
+#if (CONFIG_SYS_MDREFR_VAL & (MDREFR_K1RUN | MDREFR_K2RUN)) + and r4, r7, #( MDREFR_K1RUN | MDREFR_K2RUN | \ + MDREFR_K1DB2 | MDREFR_K2DB2 ) + ldr r6, [r3, #MDREFR_OFFSET] + orr r6, r6, r4 + str r6, [r3, #MDREFR_OFFSET] + ldr r6, [r3, #MDREFR_OFFSET] + bic r6, #MDREFR_SLFRSH str r6, [r3, #MDREFR_OFFSET] - ldr r4, [r3, #MDREFR_OFFSET] + ldr r6, [r3, #MDREFR_OFFSET]
orr r6, #MDREFR_E1PIN str r6, [r3, #MDREFR_OFFSET] - ldr r4, [r3, #MDREFR_OFFSET] + ldr r6, [r3, #MDREFR_OFFSET] +#endif
/* * 7) Write MDCNFG with MDCNFG:DEx deasserted (set to 0), to configure @@ -209,6 +230,7 @@ str r4, [r3, #MDCNFG_OFFSET] ldr r4, [r3, #MDCNFG_OFFSET]
+#if (CONFIG_SYS_MDREFR_VAL & (MDREFR_K1RUN | MDREFR_K2RUN)) /* Wait for the clock to the SDRAMs to stabilize, 100..200 usec. */ pxa_wait_ticks 0x300
@@ -226,7 +248,7 @@ .endr
/* - * 9) Write MDCNFG with enable bits asserted (MDCNFG:DEx set to 1). + * 9) Set custom MDCNFG[DEx] bits to enable required SDRAM partitions */
ldr r5, =CONFIG_SYS_MDCNFG_VAL @@ -238,19 +260,25 @@ ldr r4, [r3, #MDCNFG_OFFSET]
/* - * 10) Write MDMRS. + * 10) Write to MDMRS register to trigger an MRS command to + * all enabled banks of SDRAM. For each SDRAM partition pair + * that has one or both partitions enabled, this forces a pass + * through the MRS state and a return to NOP. */
ldr r4, =CONFIG_SYS_MDMRS_VAL str r4, [r3, #MDMRS_OFFSET] ldr r4, [r3, #MDMRS_OFFSET] +#endif
/* - * 11) Enable APD + * 11) Optionaly enable auto-power-down by setting MDREFR[APD] + * + * WARNING: APD bit is usually set. */
ldr r4, [r3, #MDREFR_OFFSET] - and r6, r6, #MDREFR_APD + and r6, r7, #MDREFR_APD orr r4, r4, r6 str r4, [r3, #MDREFR_OFFSET] ldr r4, [r3, #MDREFR_OFFSET] diff --git a/board/vpac270/lowlevel_init.S b/board/vpac270/lowlevel_init.S index ec0d12c..a327ebd 100644 --- a/board/vpac270/lowlevel_init.S +++ b/board/vpac270/lowlevel_init.S @@ -32,7 +32,7 @@ lowlevel_init: pxa_gpio_setup pxa_wait_ticks 0x8000 - pxa_mem_setup + pxa2xx_mem_setup pxa_wakeup pxa_intr_setup pxa_clock_setup